<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* This file contains functions for managing user access
*
* <b>Public API vs internals</b>
*
* General users probably only care about
*
* Context handling
* - get_context_instance()
* - get_context_instance_by_id()
* - get_parent_contexts()
* - get_child_contexts()
*
* Whether the user can do something...
* - has_capability()
* - has_any_capability()
* - has_all_capabilities()
* - require_capability()
* - require_login() (from moodlelib)
*
* What courses has this user access to?
* - get_user_courses_bycap()
*
* What users can do X in this context?
* - get_users_by_capability()
*
* Enrol/unenrol
* - enrol_into_course()
* - role_assign()/role_unassign()
*
*
* Advanced use
* - load_all_capabilities()
* - reload_all_capabilities()
* - has_capability_in_accessdata()
* - is_siteadmin()
* - get_user_access_sitewide()
* - load_subcontext()
* - get_role_access_bycontext()
*
* <b>Name conventions</b>
*
* "ctx" means context
*
* <b>accessdata</b>
*
* Access control data is held in the "accessdata" array
* which - for the logged-in user, will be in $USER->access
*
* For other users can be generated and passed around (but may also be cached
* against userid in $ACCESSLIB_PRIVATE->accessdatabyuser.
*
* $accessdata is a multidimensional array, holding
* role assignments (RAs), role-capabilities-perm sets
* (role defs) and a list of courses we have loaded
* data for.
*
* Things are keyed on "contextpaths" (the path field of
* the context table) for fast walking up/down the tree.
* <code>
* $accessdata[ra][$contextpath]= array($roleid)
* [$contextpath]= array($roleid)
* [$contextpath]= array($roleid)
* </code>
*
* Role definitions are stored like this
* (no cap merge is done - so it's compact)
*
* <code>
* $accessdata[rdef][$contextpath:$roleid][mod/forum:viewpost] = 1
* [mod/forum:editallpost] = -1
* [mod/forum:startdiscussion] = -1000
* </code>
*
* See how has_capability_in_accessdata() walks up/down the tree.
*
* Normally - specially for the logged-in user, we only load
* rdef and ra down to the course level, but not below. This
* keeps accessdata small and compact. Below-the-course ra/rdef
* are loaded as needed. We keep track of which courses we
* have loaded ra/rdef in
* <code>
* $accessdata[loaded] = array($contextpath, $contextpath)
* </code>
*
* <b>Stale accessdata</b>
*
* For the logged-in user, accessdata is long-lived.
*
* On each pageload we load $ACCESSLIB_PRIVATE->dirtycontexts which lists
* context paths affected by changes. Any check at-or-below
* a dirty context will trigger a transparent reload of accessdata.
*
* Changes at the system level will force the reload for everyone.
*
* <b>Default role caps</b>
* The default role assignment is not in the DB, so we
* add it manually to accessdata.
*
* This means that functions that work directly off the
* DB need to ensure that the default role caps
* are dealt with appropriately.
*
* @package core
* @subpackage role
* @copyright 1999 onwards Martin Dougiamas http://dougiamas.com
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
/** permission definitions */
define('CAP_INHERIT', 0);
/** permission definitions */
define('CAP_ALLOW', 1);
/** permission definitions */
define('CAP_PREVENT', -1);
/** permission definitions */
define('CAP_PROHIBIT', -1000);
/** context definitions */
define('CONTEXT_SYSTEM', 10);
/** context definitions */
define('CONTEXT_USER', 30);
/** context definitions */
define('CONTEXT_COURSECAT', 40);
/** context definitions */
define('CONTEXT_COURSE', 50);
/** context definitions */
define('CONTEXT_MODULE', 70);
/** context definitions */
define('CONTEXT_BLOCK', 80);
/** capability risks - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
define('RISK_MANAGETRUST', 0x0001);
/** capability risks - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
define('RISK_CONFIG', 0x0002);
/** capability risks - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
define('RISK_XSS', 0x0004);
/** capability risks - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
define('RISK_PERSONAL', 0x0008);
/** capability risks - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
define('RISK_SPAM', 0x0010);
/** capability risks - see {@link http://docs.moodle.org/dev/Hardening_new_Roles_system} */
define('RISK_DATALOSS', 0x0020);
/** rolename displays - the name as defined in the role definition */
define('ROLENAME_ORIGINAL', 0);
/** rolename displays - the name as defined by a role alias */
define('ROLENAME_ALIAS', 1);
/** rolename displays - Both, like this: Role alias (Original)*/
define('ROLENAME_BOTH', 2);
/** rolename displays - the name as defined in the role definition and the shortname in brackets*/
define('ROLENAME_ORIGINALANDSHORT', 3);
/** rolename displays - the name as defined by a role alias, in raw form suitable for editing*/
define('ROLENAME_ALIAS_RAW', 4);
/** rolename displays - the name is simply short role name*/
define('ROLENAME_SHORT', 5);
/**
* Internal class provides a cache of context information. The cache is
* restricted in size.
*
* This cache should NOT be used outside accesslib.php!
*
* @private
* @author Sam Marshall
*/
class context_cache {
private $contextsbyid;
private $contexts;
private $count;
/**
* @var int Maximum number of contexts that will be cached.
*/
const MAX_SIZE = 2500;
/**
* @var int Once contexts reach maximum number, this many will be removed from cache.
*/
const REDUCE_SIZE = 1000;
/**
* Initialises (empty)
*/
public function __construct() {
$this->reset();
}
/**
* Resets the cache to remove all data.
*/
public function reset() {
$this->contexts = array();
$this->contextsbyid = array();
$this->count = 0;
}
/**
* Adds a context to the cache. If the cache is full, discards a batch of
* older entries.
* @param stdClass $context New context to add
*/
public function add(stdClass $context) {
if ($this->count >= self::MAX_SIZE) {
for ($i=0; $i<self::REDUCE_SIZE; $i++) {
if ($first = reset($this->contextsbyid)) {
unset($this->contextsbyid[$first->id]);
unset($this->contexts[$first->contextlevel][$first->instanceid]);
}
}
$this->count -= self::REDUCE_SIZE;
if ($this->count < 0) {
// most probably caused by the drift, the reset() above
// might have returned false because there might not be any more elements
$this->count = 0;
}
}
$this->contexts[$context->contextlevel][$context->instanceid] = $context;
$this->contextsbyid[$context->id] = $context;
// Note the count may get out of synch slightly if you cache a context
// that is already cached, but it doesn't really matter much and I
// didn't think it was worth the performance hit.
$this->count++;
}
/**
* Removes a context from the cache.
* @param stdClass $context Context object to remove (must include fields
* ->id, ->contextlevel, ->instanceid at least)
*/
public function remove(stdClass $context) {
unset($this->contexts[$context->contextlevel][$context->instanceid]);
unset($this->contextsbyid[$context->id]);
// Again the count may get a bit out of synch if you remove things
// that don't exist
$this->count--;
if ($this->count < 0) {
$this->count = 0;
}
}
/**
* Gets a context from the cache.
* @param int $contextlevel Context level
* @param int $instance Instance ID
* @return stdClass|bool Context or false if not in cache
*/
public function get($contextlevel, $instance) {
if (isset($this->contexts[$contextlevel][$instance])) {
return $this->contexts[$contextlevel][$instance];
}
return false;
}
/**
* Gets a context from the cache based on its id.
* @param int $id Context ID
* @return stdClass|bool Context or false if not in cache
*/
public function get_by_id($id) {
if (isset($this->contextsbyid[$id])) {
return $this->contextsbyid[$id];
}
return false;
}
/**
* @return int Count of contexts in cache (approximately)
*/
public function get_approx_count() {
return $this->count;
}
}
/**
* Although this looks like a global variable, it isn't really.
*
* It is just a private implementation detail to accesslib that MUST NOT be used elsewhere.
* It is used to cache various bits of data between function calls for performance reasons.
* Sadly, a PHP global variable is the only way to implement this, without rewriting everything
* as methods of a class, instead of functions.
*
* @global stdClass $ACCESSLIB_PRIVATE
* @name $ACCESSLIB_PRIVATE
*/
global $ACCESSLIB_PRIVATE;
$ACCESSLIB_PRIVATE = new stdClass();
$ACCESSLIB_PRIVATE->contexcache = new context_cache();
$ACCESSLIB_PRIVATE->systemcontext = null; // Used in get_system_context
$ACCESSLIB_PRIVATE->dirtycontexts = null; // Dirty contexts cache
$ACCESSLIB_PRIVATE->accessdatabyuser = array(); // Holds the $accessdata structure for users other than $USER
$ACCESSLIB_PRIVATE->roledefinitions = array(); // role definitions cache - helps a lot with mem usage in cron
$ACCESSLIB_PRIVATE->croncache = array(); // Used in get_role_access
$ACCESSLIB_PRIVATE->preloadedcourses = array(); // Used in preload_course_contexts.
$ACCESSLIB_PRIVATE->capabilities = null; // detailed information about the capabilities
/**
* Clears accesslib's private caches. ONLY BE USED BY UNIT TESTS
*
* This method should ONLY BE USED BY UNIT TESTS. It clears all of
* accesslib's private caches. You need to do this before setting up test data,
* and also at the end of the tests.
*/
function accesslib_clear_all_caches_for_unit_testing() {
global $UNITTEST, $USER, $ACCESSLIB_PRIVATE;
if (empty($UNITTEST->running)) {
throw new coding_exception('You must not call clear_all_caches outside of unit tests.');
}
$ACCESSLIB_PRIVATE->contexcache = new context_cache();
$ACCESSLIB_PRIVATE->systemcontext = null;
$ACCESSLIB_PRIVATE->dirtycontexts = null;
$ACCESSLIB_PRIVATE->accessdatabyuser = array();
$ACCESSLIB_PRIVATE->roledefinitions = array();
$ACCESSLIB_PRIVATE->croncache = array();
$ACCESSLIB_PRIVATE->preloadedcourses = array();
$ACCESSLIB_PRIVATE->capabilities = null;
unset($USER->access);
}
/**
* This is really slow!!! do not use above course context level
*
* @param int $roleid
* @param object $context
* @return array
*/
function get_role_context_caps($roleid, $context) {
global $DB;
//this is really slow!!!! - do not use above course context level!
$result = array();
$result[$context->id] = array();
// first emulate the parent context capabilities merging into context
$searchcontexts = array_reverse(get_parent_contexts($context));
array_push($searchcontexts, $context->id);
foreach ($searchcontexts as $cid) {
if ($capabilities = $DB->get_records('role_capabilities', array('roleid'=>$roleid, 'contextid'=>$cid))) {
foreach ($capabilities as $cap) {
if (!array_key_exists($cap->capability, $result[$context->id])) {
$result[$context->id][$cap->capability] = 0;
}
$result[$context->id][$cap->capability] += $cap->permission;
}
}
}
// now go through the contexts bellow given context
$searchcontexts = array_keys(get_child_contexts($context));
foreach ($searchcontexts as $cid) {
if ($capabilities = $DB->get_records('role_capabilities', array('roleid'=>$roleid, 'contextid'=>$cid))) {
foreach ($capabilities as $cap) {
if (!array_key_exists($cap->contextid, $result)) {
$result[$cap->contextid] = array();
}
$result[$cap->contextid][$cap->capability] = $cap->permission;
}
}
}
return $result;
}
/**
* Gets the accessdata for role "sitewide" (system down to course)
*
* @param int $roleid
* @param array $accessdata defaults to null
* @return array
*/
function get_role_access($roleid, $accessdata = null) {
global $CFG, $DB;
/* Get it in 1 cheap DB query...
* - relevant role caps at the root and down
* to the course level - but not below
*/
if (is_null($accessdata)) {
$accessdata = array(); // named list
$accessdata['ra'] = array();
$accessdata['rdef'] = array();
$accessdata['loaded'] = array();
}
//
// Overrides for the role IN ANY CONTEXTS
// down to COURSE - not below -
//
$sql = "SELECT ctx.path,
rc.capability, rc.permission
FROM {context} ctx
JOIN {role_capabilities} rc
ON rc.contextid=ctx.id
WHERE rc.roleid = ?
AND ctx.contextlevel <= ".CONTEXT_COURSE."
ORDER BY ctx.depth, ctx.path";
$params = array($roleid);
// we need extra caching in CLI scripts and cron
if (CLI_SCRIPT) {
global $ACCESSLIB_PRIVATE;
if (!isset($ACCESSLIB_PRIVATE->croncache[$roleid])) {
$ACCESSLIB_PRIVATE->croncache[$roleid] = array();
$rs = $DB->get_recordset_sql($sql, $params);
foreach ($rs as $rd) {
$ACCESSLIB_PRIVATE->croncache[$roleid][] = $rd;
}
$rs->close();
}
foreach ($ACCESSLIB_PRIVATE->croncache[$roleid] as $rd) {
$k = "{$rd->path}:{$roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
} else {
$rs = $DB->get_recordset_sql($sql, $params);
if ($rs->valid()) {
foreach ($rs as $rd) {
$k = "{$rd->path}:{$roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
unset($rd);
}
$rs->close();
}
return $accessdata;
}
/**
* Gets the accessdata for role "sitewide" (system down to course)
*
* @param int $roleid
* @param array $accessdata defaults to null
* @return array
*/
function get_default_frontpage_role_access($roleid, $accessdata = null) {
global $CFG, $DB;
$frontpagecontext = get_context_instance(CONTEXT_COURSE, SITEID);
$base = '/'. SYSCONTEXTID .'/'. $frontpagecontext->id;
//
// Overrides for the role in any contexts related to the course
//
$sql = "SELECT ctx.path,
rc.capability, rc.permission
FROM {context} ctx
JOIN {role_capabilities} rc
ON rc.contextid=ctx.id
WHERE rc.roleid = ?
AND (ctx.id = ".SYSCONTEXTID." OR ctx.path LIKE ?)
AND ctx.contextlevel <= ".CONTEXT_COURSE."
ORDER BY ctx.depth, ctx.path";
$params = array($roleid, "$base/%");
$rs = $DB->get_recordset_sql($sql, $params);
if ($rs->valid()) {
foreach ($rs as $rd) {
$k = "{$rd->path}:{$roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
unset($rd);
}
$rs->close();
return $accessdata;
}
/**
* Get the default guest role
*
* @return stdClass role
*/
function get_guest_role() {
global $CFG, $DB;
if (empty($CFG->guestroleid)) {
if ($roles = $DB->get_records('role', array('archetype'=>'guest'))) {
$guestrole = array_shift($roles); // Pick the first one
set_config('guestroleid', $guestrole->id);
return $guestrole;
} else {
debugging('Can not find any guest role!');
return false;
}
} else {
if ($guestrole = $DB->get_record('role', array('id'=>$CFG->guestroleid))) {
return $guestrole;
} else {
//somebody is messing with guest roles, remove incorrect setting and try to find a new one
set_config('guestroleid', '');
return get_guest_role();
}
}
}
/**
* Check whether a user has a particular capability in a given context.
*
* For example::
* $context = get_context_instance(CONTEXT_MODULE, $cm->id);
* has_capability('mod/forum:replypost',$context)
*
* By default checks the capabilities of the current user, but you can pass a
* different userid. By default will return true for admin users, but you can override that with the fourth argument.
*
* Guest and not-logged-in users can never get any dangerous capability - that is any write capability
* or capabilities with XSS, config or data loss risks.
*
* @param string $capability the name of the capability to check. For example mod/forum:view
* @param object $context the context to check the capability in. You normally get this with {@link get_context_instance}.
* @param integer|object $user A user id or object. By default (null) checks the permissions of the current user.
* @param boolean $doanything If false, ignores effect of admin role assignment
* @return boolean true if the user has this capability. Otherwise false.
*/
function has_capability($capability, $context, $user = null, $doanything = true) {
global $USER, $CFG, $DB, $SCRIPT, $ACCESSLIB_PRIVATE;
if (during_initial_install()) {
if ($SCRIPT === "/$CFG->admin/index.php" or $SCRIPT === "/$CFG->admin/cliupgrade.php") {
// we are in an installer - roles can not work yet
return true;
} else {
return false;
}
}
if (strpos($capability, 'moodle/legacy:') === 0) {
throw new coding_exception('Legacy capabilities can not be used any more!');
}
// the original $CONTEXT here was hiding serious errors
// for security reasons do not reuse previous context
if (empty($context)) {
debugging('Incorrect context specified');
return false;
}
if (!is_bool($doanything)) {
throw new coding_exception('Capability parameter "doanything" is wierd ("'.$doanything.'"). This has to be fixed in code.');
}
// make sure there is a real user specified
if ($user === null) {
$userid = isset($USER->id) ? $USER->id : 0;
} else {
$userid = is_object($user) ? $user->id : $user;
}
// capability must exist
if (!$capinfo = get_capability_info($capability)) {
debugging('Capability "'.$capability.'" was not found! This should be fixed in code.');
return false;
}
// make sure the guest account and not-logged-in users never get any risky caps no matter what the actual settings are.
if (($capinfo->captype === 'write') or ((int)$capinfo->riskbitmask & (RISK_XSS | RISK_CONFIG | RISK_DATALOSS))) {
if (isguestuser($userid) or $userid == 0) {
return false;
}
}
if (is_null($context->path) or $context->depth == 0) {
//this should not happen
$contexts = array(SYSCONTEXTID, $context->id);
$context->path = '/'.SYSCONTEXTID.'/'.$context->id;
debugging('Context id '.$context->id.' does not have valid path, please use build_context_path()', DEBUG_DEVELOPER);
} else {
$contexts = explode('/', $context->path);
array_shift($contexts);
}
if (CLI_SCRIPT && !isset($USER->access)) {
// In cron, some modules setup a 'fake' $USER,
// ensure we load the appropriate accessdata.
if (isset($ACCESSLIB_PRIVATE->accessdatabyuser[$userid])) {
$ACCESSLIB_PRIVATE->dirtycontexts = null; //load fresh dirty contexts
} else {
load_user_accessdata($userid);
$ACCESSLIB_PRIVATE->dirtycontexts = array();
}
$USER->access = $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
} else if (isset($USER->id) && ($USER->id == $userid) && !isset($USER->access)) {
// caps not loaded yet - better to load them to keep BC with 1.8
// not-logged-in user or $USER object set up manually first time here
load_all_capabilities();
$ACCESSLIB_PRIVATE->accessdatabyuser = array(); // reset the cache for other users too, the dirty contexts are empty now
$ACCESSLIB_PRIVATE->roledefinitions = array();
}
// Load dirty contexts list if needed
if (!isset($ACCESSLIB_PRIVATE->dirtycontexts)) {
if (isset($USER->access['time'])) {
$ACCESSLIB_PRIVATE->dirtycontexts = get_dirty_contexts($USER->access['time']);
}
else {
$ACCESSLIB_PRIVATE->dirtycontexts = array();
}
}
// Careful check for staleness...
if (count($ACCESSLIB_PRIVATE->dirtycontexts) !== 0 and is_contextpath_dirty($contexts, $ACCESSLIB_PRIVATE->dirtycontexts)) {
// reload all capabilities - preserving loginas, roleswitches, etc
// and then cleanup any marks of dirtyness... at least from our short
// term memory! :-)
$ACCESSLIB_PRIVATE->accessdatabyuser = array();
$ACCESSLIB_PRIVATE->roledefinitions = array();
if (CLI_SCRIPT) {
load_user_accessdata($userid);
$USER->access = $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
$ACCESSLIB_PRIVATE->dirtycontexts = array();
} else {
reload_all_capabilities();
}
}
// Find out if user is admin - it is not possible to override the doanything in any way
// and it is not possible to switch to admin role either.
if ($doanything) {
if (is_siteadmin($userid)) {
if ($userid != $USER->id) {
return true;
}
// make sure switchrole is not used in this context
if (empty($USER->access['rsw'])) {
return true;
}
$parts = explode('/', trim($context->path, '/'));
$path = '';
$switched = false;
foreach ($parts as $part) {
$path .= '/' . $part;
if (!empty($USER->access['rsw'][$path])) {
$switched = true;
break;
}
}
if (!$switched) {
return true;
}
//ok, admin switched role in this context, let's use normal access control rules
}
}
// divulge how many times we are called
//// error_log("has_capability: id:{$context->id} path:{$context->path} userid:$userid cap:$capability");
if (isset($USER->id) && ($USER->id == $userid)) { // we must accept strings and integers in $userid
//
// For the logged in user, we have $USER->access
// which will have all RAs and caps preloaded for
// course and above contexts.
//
// Contexts below courses && contexts that do not
// hang from courses are loaded into $USER->access
// on demand, and listed in $USER->access[loaded]
//
if ($context->contextlevel <= CONTEXT_COURSE) {
// Course and above are always preloaded
return has_capability_in_accessdata($capability, $context, $USER->access);
}
// Load accessdata for below-the-course contexts
if (!path_inaccessdata($context->path,$USER->access)) {
// error_log("loading access for context {$context->path} for $capability at {$context->contextlevel} {$context->id}");
// $bt = debug_backtrace();
// error_log("bt {$bt[0]['file']} {$bt[0]['line']}");
load_subcontext($USER->id, $context, $USER->access);
}
return has_capability_in_accessdata($capability, $context, $USER->access);
}
if (!isset($ACCESSLIB_PRIVATE->accessdatabyuser[$userid])) {
load_user_accessdata($userid);
}
if ($context->contextlevel <= CONTEXT_COURSE) {
// Course and above are always preloaded
return has_capability_in_accessdata($capability, $context, $ACCESSLIB_PRIVATE->accessdatabyuser[$userid]);
}
// Load accessdata for below-the-course contexts as needed
if (!path_inaccessdata($context->path, $ACCESSLIB_PRIVATE->accessdatabyuser[$userid])) {
// error_log("loading access for context {$context->path} for $capability at {$context->contextlevel} {$context->id}");
// $bt = debug_backtrace();
// error_log("bt {$bt[0]['file']} {$bt[0]['line']}");
load_subcontext($userid, $context, $ACCESSLIB_PRIVATE->accessdatabyuser[$userid]);
}
return has_capability_in_accessdata($capability, $context, $ACCESSLIB_PRIVATE->accessdatabyuser[$userid]);
}
/**
* Check if the user has any one of several capabilities from a list.
*
* This is just a utility method that calls has_capability in a loop. Try to put
* the capabilities that most users are likely to have first in the list for best
* performance.
*
* There are probably tricks that could be done to improve the performance here, for example,
* check the capabilities that are already cached first.
*
* @see has_capability()
* @param array $capabilities an array of capability names.
* @param object $context the context to check the capability in. You normally get this with {@link get_context_instance}.
* @param integer $userid A user id. By default (null) checks the permissions of the current user.
* @param boolean $doanything If false, ignore effect of admin role assignment
* @return boolean true if the user has any of these capabilities. Otherwise false.
*/
function has_any_capability($capabilities, $context, $userid = null, $doanything = true) {
if (!is_array($capabilities)) {
debugging('Incorrect $capabilities parameter in has_any_capabilities() call - must be an array');
return false;
}
foreach ($capabilities as $capability) {
if (has_capability($capability, $context, $userid, $doanything)) {
return true;
}
}
return false;
}
/**
* Check if the user has all the capabilities in a list.
*
* This is just a utility method that calls has_capability in a loop. Try to put
* the capabilities that fewest users are likely to have first in the list for best
* performance.
*
* There are probably tricks that could be done to improve the performance here, for example,
* check the capabilities that are already cached first.
*
* @see has_capability()
* @param array $capabilities an array of capability names.
* @param object $context the context to check the capability in. You normally get this with {@link get_context_instance}.
* @param integer $userid A user id. By default (null) checks the permissions of the current user.
* @param boolean $doanything If false, ignore effect of admin role assignment
* @return boolean true if the user has all of these capabilities. Otherwise false.
*/
function has_all_capabilities($capabilities, $context, $userid = null, $doanything = true) {
if (!is_array($capabilities)) {
debugging('Incorrect $capabilities parameter in has_all_capabilities() call - must be an array');
return false;
}
foreach ($capabilities as $capability) {
if (!has_capability($capability, $context, $userid, $doanything)) {
return false;
}
}
return true;
}
/**
* Check if the user is an admin at the site level.
*
* Please note that use of proper capabilities is always encouraged,
* this function is supposed to be used from core or for temporary hacks.
*
* @param int|object $user_or_id user id or user object
* @returns bool true if user is one of the administrators, false otherwise
*/
function is_siteadmin($user_or_id = null) {
global $CFG, $USER;
if ($user_or_id === null) {
$user_or_id = $USER;
}
if (empty($user_or_id)) {
return false;
}
if (!empty($user_or_id->id)) {
// we support
$userid = $user_or_id->id;
} else {
$userid = $user_or_id;
}
$siteadmins = explode(',', $CFG->siteadmins);
return in_array($userid, $siteadmins);
}
/**
* Returns true if user has at least one role assign
* of 'coursecontact' role (is potentially listed in some course descriptions).
*
* @param $userid
* @return stdClass
*/
function has_coursecontact_role($userid) {
global $DB, $CFG;
if (empty($CFG->coursecontact)) {
return false;
}
$sql = "SELECT 1
FROM {role_assignments}
WHERE userid = :userid AND roleid IN ($CFG->coursecontact)";
return $DB->record_exists_sql($sql, array('userid'=>$userid));
}
/**
* @param string $path
* @return string
*/
function get_course_from_path($path) {
// assume that nothing is more than 1 course deep
if (preg_match('!^(/.+)/\d+$!', $path, $matches)) {
return $matches[1];
}
return false;
}
/**
* @param string $path
* @param array $accessdata
* @return bool
*/
function path_inaccessdata($path, $accessdata) {
if (empty($accessdata['loaded'])) {
return false;
}
// assume that contexts hang from sys or from a course
// this will only work well with stuff that hangs from a course
if (in_array($path, $accessdata['loaded'], true)) {
// error_log("found it!");
return true;
}
$base = '/' . SYSCONTEXTID;
while (preg_match('!^(/.+)/\d+$!', $path, $matches)) {
$path = $matches[1];
if ($path === $base) {
return false;
}
if (in_array($path, $accessdata['loaded'], true)) {
return true;
}
}
return false;
}
/**
* Does the user have a capability to do something?
*
* Walk the accessdata array and return true/false.
* Deals with prohibits, roleswitching, aggregating
* capabilities, etc.
*
* The main feature of here is being FAST and with no
* side effects.
*
* Notes:
*
* Switch Roles exits early
* ------------------------
* cap checks within a switchrole need to exit early
* in our bottom up processing so they don't "see" that
* there are real RAs that can do all sorts of things.
*
* Switch Role merges with default role
* ------------------------------------
* If you are a teacher in course X, you have at least
* teacher-in-X + defaultloggedinuser-sitewide. So in the
* course you'll have techer+defaultloggedinuser.
* We try to mimic that in switchrole.
*
* Permission evaluation
* ---------------------
* Originally there was an extremely complicated way
* to determine the user access that dealt with
* "locality" or role assignments and role overrides.
* Now we simply evaluate access for each role separately
* and then verify if user has at least one role with allow
* and at the same time no role with prohibit.
*
* @param string $capability
* @param object $context
* @param array $accessdata
* @return bool
*/
function has_capability_in_accessdata($capability, $context, array $accessdata) {
global $CFG;
if (empty($context->id)) {
throw new coding_exception('Invalid context specified');
}
// Build $paths as a list of current + all parent "paths" with order bottom-to-top
$contextids = explode('/', trim($context->path, '/'));
$paths = array($context->path);
while ($contextids) {
array_pop($contextids);
$paths[] = '/' . implode('/', $contextids);
}
unset($contextids);
$roles = array();
$switchedrole = false;
// Find out if role switched
if (!empty($accessdata['rsw'])) {
// From the bottom up...
foreach ($paths as $path) {
if (isset($accessdata['rsw'][$path])) {
// Found a switchrole assignment - check for that role _plus_ the default user role
$roles = array($accessdata['rsw'][$path]=>null, $CFG->defaultuserroleid=>null);
$switchedrole = true;
break;
}
}
}
if (!$switchedrole) {
// get all users roles in this context and above
foreach ($paths as $path) {
if (isset($accessdata['ra'][$path])) {
foreach ($accessdata['ra'][$path] as $roleid) {
$roles[$roleid] = null;
}
}
}
}
// Now find out what access is given to each role, going bottom-->up direction
foreach ($roles as $roleid => $ignored) {
foreach ($paths as $path) {
if (isset($accessdata['rdef']["{$path}:$roleid"][$capability])) {
$perm = (int)$accessdata['rdef']["{$path}:$roleid"][$capability];
if ($perm === CAP_PROHIBIT or is_null($roles[$roleid])) {
$roles[$roleid] = $perm;
}
}
}
}
// any CAP_PROHIBIT found means no permission for the user
if (array_search(CAP_PROHIBIT, $roles) !== false) {
return false;
}
// at least one CAP_ALLOW means the user has a permission
return (array_search(CAP_ALLOW, $roles) !== false);
}
/**
* @param object $context
* @param array $accessdata
* @return array
*/
function aggregate_roles_from_accessdata($context, $accessdata) {
$path = $context->path;
// build $contexts as a list of "paths" of the current
// contexts and parents with the order top-to-bottom
$contexts = array($path);
while (preg_match('!^(/.+)/\d+$!', $path, $matches)) {
$path = $matches[1];
array_unshift($contexts, $path);
}
$cc = count($contexts);
$roles = array();
// From the bottom up...
for ($n=$cc-1; $n>=0; $n--) {
$ctxp = $contexts[$n];
if (isset($accessdata['ra'][$ctxp]) && count($accessdata['ra'][$ctxp])) {
// Found assignments on this leaf
$addroles = $accessdata['ra'][$ctxp];
$roles = array_merge($roles, $addroles);
}
}
return array_unique($roles);
}
/**
* A convenience function that tests has_capability, and displays an error if
* the user does not have that capability.
*
* NOTE before Moodle 2.0, this function attempted to make an appropriate
* require_login call before checking the capability. This is no longer the case.
* You must call require_login (or one of its variants) if you want to check the
* user is logged in, before you call this function.
*
* @see has_capability()
*
* @param string $capability the name of the capability to check. For example mod/forum:view
* @param object $context the context to check the capability in. You normally get this with {@link get_context_instance}.
* @param integer $userid A user id. By default (null) checks the permissions of the current user.
* @param bool $doanything If false, ignore effect of admin role assignment
* @param string $errorstring The error string to to user. Defaults to 'nopermissions'.
* @param string $stringfile The language file to load the error string from. Defaults to 'error'.
* @return void terminates with an error if the user does not have the given capability.
*/
function require_capability($capability, $context, $userid = null, $doanything = true,
$errormessage = 'nopermissions', $stringfile = '') {
if (!has_capability($capability, $context, $userid, $doanything)) {
throw new required_capability_exception($context, $capability, $errormessage, $stringfile);
}
}
/**
* Get an array of courses where cap requested is available
* and user is enrolled, this can be relatively slow.
*
* @param string $capability - name of the capability
* @param array $accessdata_ignored
* @param bool $doanything_ignored
* @param string $sort - sorting fields - prefix each fieldname with "c."
* @param array $fields - additional fields you are interested in...
* @param int $limit_ignored
* @return array $courses - ordered array of course objects - see notes above
*/
function get_user_courses_bycap($userid, $cap, $accessdata_ignored, $doanything_ignored, $sort = 'c.sortorder ASC', $fields = null, $limit_ignored = 0) {
//TODO: this should be most probably deprecated
$courses = enrol_get_users_courses($userid, true, $fields, $sort);
foreach ($courses as $id=>$course) {
$context = get_context_instance(CONTEXT_COURSE, $id);
if (!has_capability($cap, $context, $userid)) {
unset($courses[$id]);
}
}
return $courses;
}
/**
* Return a nested array showing role assignments
* all relevant role capabilities for the user at
* site/course_category/course levels
*
* We do _not_ delve deeper than courses because the number of
* overrides at the module/block levels is HUGE.
*
* [ra] => [/path/][]=roleid
* [rdef] => [/path/:roleid][capability]=permission
* [loaded] => array('/path', '/path')
*
* @param int $userid - the id of the user
* @return array
*/
function get_user_access_sitewide($userid) {
global $CFG, $DB;
/* Get in 3 cheap DB queries...
* - role assignments
* - relevant role caps
* - above and within this user's RAs
* - below this user's RAs - limited to course level
*/
$accessdata = array(); // named list
$accessdata['ra'] = array();
$accessdata['rdef'] = array();
$accessdata['loaded'] = array();
//
// Role assignments
//
$sql = "SELECT ctx.path, ra.roleid
FROM {role_assignments} ra
JOIN {context} ctx ON ctx.id=ra.contextid
WHERE ra.userid = ? AND ctx.contextlevel <= ".CONTEXT_COURSE;
$params = array($userid);
$rs = $DB->get_recordset_sql($sql, $params);
//
// raparents collects paths & roles we need to walk up
// the parenthood to build the rdef
//
$raparents = array();
if ($rs) {
foreach ($rs as $ra) {
// RAs leafs are arrays to support multi
// role assignments...
if (!isset($accessdata['ra'][$ra->path])) {
$accessdata['ra'][$ra->path] = array();
}
$accessdata['ra'][$ra->path][$ra->roleid] = $ra->roleid;
// Concatenate as string the whole path (all related context)
// for this role. This is damn faster than using array_merge()
// Will unique them later
if (isset($raparents[$ra->roleid])) {
$raparents[$ra->roleid] .= $ra->path;
} else {
$raparents[$ra->roleid] = $ra->path;
}
}
unset($ra);
$rs->close();
}
// Walk up the tree to grab all the roledefs
// of interest to our user...
//
// NOTE: we use a series of IN clauses here - which
// might explode on huge sites with very convoluted nesting of
// categories... - extremely unlikely that the number of categories
// and roletypes is so large that we hit the limits of IN()
$clauses = '';
$cparams = array();
foreach ($raparents as $roleid=>$strcontexts) {
$contexts = implode(',', array_unique(explode('/', trim($strcontexts, '/'))));
if ($contexts ==! '') {
if ($clauses) {
$clauses .= ' OR ';
}
$clauses .= "(roleid=? AND contextid IN ($contexts))";
$cparams[] = $roleid;
}
}
if ($clauses !== '') {
$sql = "SELECT ctx.path, rc.roleid, rc.capability, rc.permission
FROM {role_capabilities} rc
JOIN {context} ctx ON rc.contextid=ctx.id
WHERE $clauses";
unset($clauses);
$rs = $DB->get_recordset_sql($sql, $cparams);
if ($rs) {
foreach ($rs as $rd) {
$k = "{$rd->path}:{$rd->roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
unset($rd);
$rs->close();
}
}
//
// Overrides for the role assignments IN SUBCONTEXTS
// (though we still do _not_ go below the course level.
//
// NOTE that the JOIN w sctx is with 3-way triangulation to
// catch overrides to the applicable role in any subcontext, based
// on the path field of the parent.
//
$sql = "SELECT sctx.path, ra.roleid,
ctx.path AS parentpath,
rco.capability, rco.permission
FROM {role_assignments} ra
JOIN {context} ctx
ON ra.contextid=ctx.id
JOIN {context} sctx
ON (sctx.path LIKE " . $DB->sql_concat('ctx.path',"'/%'"). " )
JOIN {role_capabilities} rco
ON (rco.roleid=ra.roleid AND rco.contextid=sctx.id)
WHERE ra.userid = ?
AND ctx.contextlevel <= ".CONTEXT_COURSECAT."
AND sctx.contextlevel <= ".CONTEXT_COURSE."
ORDER BY sctx.depth, sctx.path, ra.roleid";
$params = array($userid);
$rs = $DB->get_recordset_sql($sql, $params);
if ($rs) {
foreach ($rs as $rd) {
$k = "{$rd->path}:{$rd->roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
unset($rd);
$rs->close();
}
return $accessdata;
}
/**
* Add to the access ctrl array the data needed by a user for a given context
*
* @param integer $userid the id of the user
* @param object $context needs path!
* @param array $accessdata accessdata array
* @return void
*/
function load_subcontext($userid, $context, &$accessdata) {
global $CFG, $DB;
/* Get the additional RAs and relevant rolecaps
* - role assignments - with role_caps
* - relevant role caps
* - above this user's RAs
* - below this user's RAs - limited to course level
*/
$base = "/" . SYSCONTEXTID;
//
// Replace $context with the target context we will
// load. Normally, this will be a course context, but
// may be a different top-level context.
//
// We have 3 cases
//
// - Course
// - BLOCK/PERSON/USER/COURSE(sitecourse) hanging from SYSTEM
// - BLOCK/MODULE/GROUP hanging from a course
//
// For course contexts, we _already_ have the RAs
// but the cost of re-fetching is minimal so we don't care.
//
if ($context->contextlevel !== CONTEXT_COURSE
&& $context->path !== "$base/{$context->id}") {
// Case BLOCK/MODULE/GROUP hanging from a course
// Assumption: the course _must_ be our parent
// If we ever see stuff nested further this needs to
// change to do 1 query over the exploded path to
// find out which one is the course
$courses = explode('/',get_course_from_path($context->path));
$targetid = array_pop($courses);
$context = get_context_instance_by_id($targetid);
}
//
// Role assignments in the context and below
//
$sql = "SELECT ctx.path, ra.roleid
FROM {role_assignments} ra
JOIN {context} ctx
ON ra.contextid=ctx.id
WHERE ra.userid = ?
AND (ctx.path = ? OR ctx.path LIKE ?)
ORDER BY ctx.depth, ctx.path, ra.roleid";
$params = array($userid, $context->path, $context->path."/%");
$rs = $DB->get_recordset_sql($sql, $params);
//
// Read in the RAs, preventing duplicates
//
if ($rs) {
$localroles = array();
$lastseen = '';
foreach ($rs as $ra) {
if (!isset($accessdata['ra'][$ra->path])) {
$accessdata['ra'][$ra->path] = array();
}
// only add if is not a repeat caused
// by capability join...
// (this check is cheaper than in_array())
if ($lastseen !== $ra->path.':'.$ra->roleid) {
$lastseen = $ra->path.':'.$ra->roleid;
$accessdata['ra'][$ra->path][$ra->roleid] = $ra->roleid;
array_push($localroles, $ra->roleid);
}
}
$rs->close();
}
//
// Walk up and down the tree to grab all the roledefs
// of interest to our user...
//
// NOTES
// - we use IN() but the number of roles is very limited.
//
$courseroles = aggregate_roles_from_accessdata($context, $accessdata);
// Do we have any interesting "local" roles?
$localroles = array_diff($localroles,$courseroles); // only "new" local roles
$wherelocalroles='';
if (count($localroles)) {
// Role defs for local roles in 'higher' contexts...
$contexts = substr($context->path, 1); // kill leading slash
$contexts = str_replace('/', ',', $contexts);
$localroleids = implode(',',$localroles);
$wherelocalroles="OR (rc.roleid IN ({$localroleids})
AND ctx.id IN ($contexts))" ;
}
// We will want overrides for all of them
$whereroles = '';
if ($roleids = implode(',',array_merge($courseroles,$localroles))) {
$whereroles = "rc.roleid IN ($roleids) AND";
}
$sql = "SELECT ctx.path, rc.roleid, rc.capability, rc.permission
FROM {role_capabilities} rc
JOIN {context} ctx
ON rc.contextid=ctx.id
WHERE ($whereroles
(ctx.id=? OR ctx.path LIKE ?))
$wherelocalroles
ORDER BY ctx.depth ASC, ctx.path DESC, rc.roleid ASC ";
$params = array($context->id, $context->path."/%");
$newrdefs = array();
$rs = $DB->get_recordset_sql($sql, $params);
foreach ($rs as $rd) {
$k = "{$rd->path}:{$rd->roleid}";
if (!array_key_exists($k, $newrdefs)) {
$newrdefs[$k] = array();
}
$newrdefs[$k][$rd->capability] = $rd->permission;
}
$rs->close();
compact_rdefs($newrdefs);
foreach ($newrdefs as $key=>$value) {
$accessdata['rdef'][$key] =& $newrdefs[$key];
}
// error_log("loaded {$context->path}");
$accessdata['loaded'][] = $context->path;
}
/**
* Add to the access ctrl array the data needed by a role for a given context.
*
* The data is added in the rdef key.
*
* This role-centric function is useful for role_switching
* and to get an overview of what a role gets under a
* given context and below...
*
* @param integer $roleid the id of the user
* @param object $context needs path!
* @param array $accessdata accessdata array null by default
* @return array
*/
function get_role_access_bycontext($roleid, $context, $accessdata = null) {
global $CFG, $DB;
/* Get the relevant rolecaps into rdef
* - relevant role caps
* - at ctx and above
* - below this ctx
*/
if (is_null($accessdata)) {
$accessdata = array(); // named list
$accessdata['ra'] = array();
$accessdata['rdef'] = array();
$accessdata['loaded'] = array();
}
$contexts = substr($context->path, 1); // kill leading slash
$contexts = str_replace('/', ',', $contexts);
//
// Walk up and down the tree to grab all the roledefs
// of interest to our role...
//
// NOTE: we use an IN clauses here - which
// might explode on huge sites with very convoluted nesting of
// categories... - extremely unlikely that the number of nested
// categories is so large that we hit the limits of IN()
//
$sql = "SELECT ctx.path, rc.capability, rc.permission
FROM {role_capabilities} rc
JOIN {context} ctx
ON rc.contextid=ctx.id
WHERE rc.roleid=? AND
( ctx.id IN ($contexts) OR
ctx.path LIKE ? )
ORDER BY ctx.depth ASC, ctx.path DESC, rc.roleid ASC ";
$params = array($roleid, $context->path."/%");
$rs = $DB->get_recordset_sql($sql, $params);
foreach ($rs as $rd) {
$k = "{$rd->path}:{$roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
$rs->close();
return $accessdata;
}
/**
* Load accessdata for a user into the $ACCESSLIB_PRIVATE->accessdatabyuser global
*
* Used by has_capability() - but feel free
* to call it if you are about to run a BIG
* cron run across a bazillion users.
*
* @param int $userid
* @return array returns ACCESSLIB_PRIVATE->accessdatabyuser[userid]
*/
function load_user_accessdata($userid) {
global $CFG, $ACCESSLIB_PRIVATE;
$base = '/'.SYSCONTEXTID;
$accessdata = get_user_access_sitewide($userid);
$frontpagecontext = get_context_instance(CONTEXT_COURSE, SITEID);
//
// provide "default role" & set 'dr'
//
if (!empty($CFG->defaultuserroleid)) {
$accessdata = get_role_access($CFG->defaultuserroleid, $accessdata);
if (!isset($accessdata['ra'][$base])) {
$accessdata['ra'][$base] = array();
}
$accessdata['ra'][$base][$CFG->defaultuserroleid] = $CFG->defaultuserroleid;
$accessdata['dr'] = $CFG->defaultuserroleid;
}
//
// provide "default frontpage role"
//
if (!empty($CFG->defaultfrontpageroleid)) {
$base = '/'. SYSCONTEXTID .'/'. $frontpagecontext->id;
$accessdata = get_default_frontpage_role_access($CFG->defaultfrontpageroleid, $accessdata);
if (!isset($accessdata['ra'][$base])) {
$accessdata['ra'][$base] = array();
}
$accessdata['ra'][$base][$CFG->defaultfrontpageroleid] = $CFG->defaultfrontpageroleid;
}
// for dirty timestamps in cron
$accessdata['time'] = time();
$ACCESSLIB_PRIVATE->accessdatabyuser[$userid] = $accessdata;
compact_rdefs($ACCESSLIB_PRIVATE->accessdatabyuser[$userid]['rdef']);
return $ACCESSLIB_PRIVATE->accessdatabyuser[$userid];
}
/**
* Use shared copy of role definitions stored in ACCESSLIB_PRIVATE->roledefinitions;
*
* @param array $rdefs array of role definitions in contexts
*/
function compact_rdefs(&$rdefs) {
global $ACCESSLIB_PRIVATE;
/*
* This is a basic sharing only, we could also
* use md5 sums of values. The main purpose is to
* reduce mem in cron jobs - many users in $ACCESSLIB_PRIVATE->accessdatabyuser array.
*/
foreach ($rdefs as $key => $value) {
if (!array_key_exists($key, $ACCESSLIB_PRIVATE->roledefinitions)) {
$ACCESSLIB_PRIVATE->roledefinitions[$key] = $rdefs[$key];
}
$rdefs[$key] =& $ACCESSLIB_PRIVATE->roledefinitions[$key];
}
}
/**
* A convenience function to completely load all the capabilities
* for the current user. This is what gets called from complete_user_login()
* for example. Call it only _after_ you've setup $USER and called
* check_enrolment_plugins();
* @see check_enrolment_plugins()
*
* @return void
*/
function load_all_capabilities() {
global $CFG, $ACCESSLIB_PRIVATE;
//NOTE: we can not use $USER here because it may no be linked to $_SESSION['USER'] yet!
// roles not installed yet - we are in the middle of installation
if (during_initial_install()) {
return;
}
$base = '/'.SYSCONTEXTID;
if (isguestuser($_SESSION['USER'])) {
$guest = get_guest_role();
// Load the rdefs
$_SESSION['USER']->access = get_role_access($guest->id);
// Put the ghost enrolment in place...
$_SESSION['USER']->access['ra'][$base] = array($guest->id => $guest->id);
} else if (!empty($_SESSION['USER']->id)) { // can not use isloggedin() yet
$accessdata = get_user_access_sitewide($_SESSION['USER']->id);
//
// provide "default role" & set 'dr'
//
if (!empty($CFG->defaultuserroleid)) {
$accessdata = get_role_access($CFG->defaultuserroleid, $accessdata);
if (!isset($accessdata['ra'][$base])) {
$accessdata['ra'][$base] = array();
}
$accessdata['ra'][$base][$CFG->defaultuserroleid] = $CFG->defaultuserroleid;
$accessdata['dr'] = $CFG->defaultuserroleid;
}
$frontpagecontext = get_context_instance(CONTEXT_COURSE, SITEID);
//
// provide "default frontpage role"
//
if (!empty($CFG->defaultfrontpageroleid)) {
$base = '/'. SYSCONTEXTID .'/'. $frontpagecontext->id;
$accessdata = get_default_frontpage_role_access($CFG->defaultfrontpageroleid, $accessdata);
if (!isset($accessdata['ra'][$base])) {
$accessdata['ra'][$base] = array();
}
$accessdata['ra'][$base][$CFG->defaultfrontpageroleid] = $CFG->defaultfrontpageroleid;
}
$_SESSION['USER']->access = $accessdata;
} else if (!empty($CFG->notloggedinroleid)) {
$_SESSION['USER']->access = get_role_access($CFG->notloggedinroleid);
$_SESSION['USER']->access['ra'][$base] = array($CFG->notloggedinroleid => $CFG->notloggedinroleid);
}
// Timestamp to read dirty context timestamps later
$_SESSION['USER']->access['time'] = time();
$ACCESSLIB_PRIVATE->dirtycontexts = array();
// Clear to force a refresh
unset($_SESSION['USER']->mycourses);
}
/**
* A convenience function to completely reload all the capabilities
* for the current user when roles have been updated in a relevant
* context -- but PRESERVING switchroles and loginas.
*
* That is - completely transparent to the user.
*
* Note: rewrites $USER->access completely.
*
* @return void
*/
function reload_all_capabilities() {
global $USER, $DB;
// error_log("reloading");
// copy switchroles
$sw = array();
if (isset($USER->access['rsw'])) {
$sw = $USER->access['rsw'];
// error_log(print_r($sw,1));
}
unset($USER->access);
unset($USER->mycourses);
load_all_capabilities();
foreach ($sw as $path => $roleid) {
$context = $DB->get_record('context', array('path'=>$path));
role_switch($roleid, $context);
}
}
/**
* Adds a temp role to an accessdata array.
*
* Useful for the "temporary guest" access
* we grant to logged-in users.
*
* Note - assumes a course context!
*
* @param object $content
* @param int $roleid
* @param array $accessdata
* @return array Returns access data
*/
function load_temp_role($context, $roleid, array $accessdata) {
global $CFG, $DB;
//
// Load rdefs for the role in -
// - this context
// - all the parents
// - and below - IOWs overrides...
//
// turn the path into a list of context ids
$contexts = substr($context->path, 1); // kill leading slash
$contexts = str_replace('/', ',', $contexts);
$sql = "SELECT ctx.path, rc.capability, rc.permission
FROM {context} ctx
JOIN {role_capabilities} rc
ON rc.contextid=ctx.id
WHERE (ctx.id IN ($contexts)
OR ctx.path LIKE ?)
AND rc.roleid = ?
ORDER BY ctx.depth, ctx.path";
$params = array($context->path."/%", $roleid);
$rs = $DB->get_recordset_sql($sql, $params);
foreach ($rs as $rd) {
$k = "{$rd->path}:{$roleid}";
$accessdata['rdef'][$k][$rd->capability] = $rd->permission;
}
$rs->close();
//
// Say we loaded everything for the course context
// - which we just did - if the user gets a proper
// RA in this session, this data will need to be reloaded,
// but that is handled by the complete accessdata reload
//
array_push($accessdata['loaded'], $context->path);
//
// Add the ghost RA
//
if (!isset($accessdata['ra'][$context->path])) {
$accessdata['ra'][$context->path] = array();
}
$accessdata['ra'][$context->path][$roleid] = $roleid;
return $accessdata;
}
/**
* Removes any extra guest roles from accessdata
* @param object $context
* @param array $accessdata
* @return array access data
*/
function remove_temp_roles($context, array $accessdata) {
global $DB, $USER;
$sql = "SELECT DISTINCT ra.roleid AS id
FROM {role_assignments} ra
WHERE ra.contextid = :contextid AND ra.userid = :userid";
$ras = $DB->get_records_sql($sql, array('contextid'=>$context->id, 'userid'=>$USER->id));
if ($ras) {
$accessdata['ra'][$context->path] = array_combine(array_keys($ras), array_keys($ras));
} else {
$accessdata['ra'][$context->path] = array();
}
return $accessdata;
}
/**
* Returns array of all role archetypes.
*
* @return array
*/
function get_role_archetypes() {
return array(
'manager' => 'manager',
'coursecreator' => 'coursecreator',
'editingteacher' => 'editingteacher',
'teacher' => 'teacher',
'student' => 'student',
'guest' => 'guest',
'user' => 'user',
'frontpage' => 'frontpage'
);
}
/**
* Assign the defaults found in this capability definition to roles that have
* the corresponding legacy capabilities assigned to them.
*
* @param string $capability
* @param array $legacyperms an array in the format (example):
* 'guest' => CAP_PREVENT,
* 'student' => CAP_ALLOW,
* 'teacher' => CAP_ALLOW,
* 'editingteacher' => CAP_ALLOW,
* 'coursecreator' => CAP_ALLOW,
* 'manager' => CAP_ALLOW
* @return boolean success or failure.
*/
function assign_legacy_capabilities($capability, $legacyperms) {
$archetypes = get_role_archetypes();
foreach ($legacyperms as $type => $perm) {
$systemcontext = get_context_instance(CONTEXT_SYSTEM);
if ($type === 'admin') {
debugging('Legacy type admin in access.php was renamed to manager, please update the code.');
$type = 'manager';
}
if (!array_key_exists($type, $archetypes)) {
print_error('invalidlegacy', '', '', $type);
}
if ($roles = get_archetype_roles($type)) {
foreach ($roles as $role) {
// Assign a site level capability.
if (!assign_capability($capability, $perm, $role->id, $systemcontext->id)) {
return false;
}
}
}
}
return true;
}
/**
* @param object $capability a capability - a row from the capabilities table.
* @return boolean whether this capability is safe - that is, whether people with the
* safeoverrides capability should be allowed to change it.
*/
function is_safe_capability($capability) {
return !((RISK_DATALOSS | RISK_MANAGETRUST | RISK_CONFIG | RISK_XSS | RISK_PERSONAL) & $capability->riskbitmask);
}
/**********************************
* Context Manipulation functions *
**********************************/
/**
* Context creation - internal implementation.
*
* Create a new context record for use by all roles-related stuff
* assumes that the caller has done the homework.
*
* DO NOT CALL THIS DIRECTLY, instead use {@link get_context_instance}!
*
* @param int $contextlevel
* @param int $instanceid
* @param int $strictness
* @return object newly created context
*/
function create_context($contextlevel, $instanceid, $strictness = IGNORE_MISSING) {
global $CFG, $DB;
if ($contextlevel == CONTEXT_SYSTEM) {
return get_system_context();
}
$context = new stdClass();
$context->contextlevel = $contextlevel;
$context->instanceid = $instanceid;
// Define $context->path based on the parent
// context. In other words... Who is your daddy?
$basepath = '/' . SYSCONTEXTID;
$basedepth = 1;
$result = true;
$error_message = null;
switch ($contextlevel) {
case CONTEXT_COURSECAT:
$sql = "SELECT ctx.path, ctx.depth
FROM {context} ctx
JOIN {course_categories} cc
ON (cc.parent=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSECAT.")
WHERE cc.id=?";
$params = array($instanceid);
if ($p = $DB->get_record_sql($sql, $params)) {
$basepath = $p->path;
$basedepth = $p->depth;
} else if ($category = $DB->get_record('course_categories', array('id'=>$instanceid), '*', $strictness)) {
if (empty($category->parent)) {
// ok - this is a top category
} else if ($parent = get_context_instance(CONTEXT_COURSECAT, $category->parent)) {
$basepath = $parent->path;
$basedepth = $parent->depth;
} else {
// wrong parent category - no big deal, this can be fixed later
$basepath = null;
$basedepth = 0;
}
} else {
// incorrect category id
$error_message = "incorrect course category id ($instanceid)";
$result = false;
}
break;
case CONTEXT_COURSE:
$sql = "SELECT ctx.path, ctx.depth
FROM {context} ctx
JOIN {course} c
ON (c.category=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSECAT.")
WHERE c.id=? AND c.id !=" . SITEID;
$params = array($instanceid);
if ($p = $DB->get_record_sql($sql, $params)) {
$basepath = $p->path;
$basedepth = $p->depth;
} else if ($course = $DB->get_record('course', array('id'=>$instanceid), '*', $strictness)) {
if ($course->id == SITEID) {
//ok - no parent category
} else if ($parent = get_context_instance(CONTEXT_COURSECAT, $course->category)) {
$basepath = $parent->path;
$basedepth = $parent->depth;
} else {
// wrong parent category of course - no big deal, this can be fixed later
$basepath = null;
$basedepth = 0;
}
} else if ($instanceid == SITEID) {
// no errors for missing site course during installation
return false;
} else {
// incorrect course id
$error_message = "incorrect course id ($instanceid)";
$result = false;
}
break;
case CONTEXT_MODULE:
$sql = "SELECT ctx.path, ctx.depth
FROM {context} ctx
JOIN {course_modules} cm
ON (cm.course=ctx.instanceid AND ctx.contextlevel=".CONTEXT_COURSE.")
WHERE cm.id=?";
$params = array($instanceid);
if ($p = $DB->get_record_sql($sql, $params)) {
$basepath = $p->path;
$basedepth = $p->depth;
} else if ($cm = $DB->get_record('course_modules', array('id'=>$instanceid), '*', $strictness)) {
if ($parent = get_context_instance(CONTEXT_COURSE, $cm->course, $strictness)) {
$basepath = $parent->path;
$basedepth = $parent->depth;
} else {
// course does not exist - modules can not exist without a course
$error_message = "course does not exist ($cm->course) - modules can not exist without a course";
$result = false;
}
} else {
// cm does not exist
$error_message = "cm with id $instanceid does not exist";
$result = false;
}
break;
case CONTEXT_BLOCK:
$sql = "SELECT ctx.path, ctx.depth
FROM {context} ctx
JOIN {block_instances} bi ON (bi.parentcontextid=ctx.id)
WHERE bi.id = ?";
$params = array($instanceid, CONTEXT_COURSE);
if ($p = $DB->get_record_sql($sql, $params, '*', $strictness)) {
$basepath = $p->path;
$basedepth = $p->depth;
} else {
// block does not exist
$error_message = 'block or parent context does not exist';
$result = false;
}
break;
case CONTEXT_USER:
// default to basepath
break;
}
// if grandparents unknown, maybe rebuild_context_path() will solve it later
if ($basedepth != 0) {
$context->depth = $basedepth+1;
}
if (!$result) {
debugging('Error: could not insert new context level "'.
s($contextlevel).'", instance "'.
s($instanceid).'". ' . $error_message);
return false;
}
$id = $DB->insert_record('context', $context);
// can't set the full path till we know the id!
if ($basedepth != 0 and !empty($basepath)) {
$DB->set_field('context', 'path', $basepath.'/'. $id, array('id'=>$id));
}
return get_context_instance_by_id($id);
}
/**
* Returns system context or null if can not be created yet.
*
* @param bool $cache use caching
* @return mixed system context or null
*/
function get_system_context($cache = true) {
global $DB, $ACCESSLIB_PRIVATE;
if ($cache and defined('SYSCONTEXTID')) {
if (is_null($ACCESSLIB_PRIVATE->systemcontext)) {
$ACCESSLIB_PRIVATE->systemcontext = new stdClass();
$ACCESSLIB_PRIVATE->systemcontext->id = SYSCONTEXTID;
$ACCESSLIB_PRIVATE->systemcontext->contextlevel = CONTEXT_SYSTEM;
$ACCESSLIB_PRIVATE->systemcontext->instanceid = 0;
$ACCESSLIB_PRIVATE->systemcontext->path = '/'.SYSCONTEXTID;
$ACCESSLIB_PRIVATE->systemcontext->depth = 1;
}
return $ACCESSLIB_PRIVATE->systemcontext;
}
try {
$context = $DB->get_record('context', array('contextlevel'=>CONTEXT_SYSTEM));
} catch (dml_exception $e) {
//table does not exist yet, sorry
return null;
}
if (!$context) {
$context = new stdClass();
$context->contextlevel = CONTEXT_SYSTEM;
$context->instanceid = 0;
$context->depth = 1;
$context->path = null; //not known before insert
try {
$context->id = $DB->insert_record('context', $context);
} catch (dml_exception $e) {
// can not create context yet, sorry
return null;
}
}
if (!isset($context->depth) or $context->depth != 1 or $context->instanceid != 0 or $context->path != '/'.$context->id) {
$context->instanceid = 0;
$context->path = '/'.$context->id;
$context->depth = 1;
$DB->update_record('context', $context);
}
if (!defined('SYSCONTEXTID')) {
define('SYSCONTEXTID', $context->id);
}
$ACCESSLIB_PRIVATE->systemcontext = $context;
return $ACCESSLIB_PRIVATE->systemcontext;
}
/**
* Remove a context record and any dependent entries,
* removes context from static context cache too
*
* @param int $level
* @param int $instanceid
* @param bool $deleterecord false means keep record for now
* @return bool returns true or throws an exception
*/
function delete_context($contextlevel, $instanceid, $deleterecord = true) {
global $DB, $ACCESSLIB_PRIVATE, $CFG;
// do not use get_context_instance(), because the related object might not exist,
// or the context does not exist yet and it would be created now
if ($context = $DB->get_record('context', array('contextlevel'=>$contextlevel, 'instanceid'=>$instanceid))) {
// delete these first because they might fetch the context and try to recreate it!
blocks_delete_all_for_context($context->id);
filter_delete_all_for_context($context->id);
require_once($CFG->dirroot . '/comment/lib.php');
comment::delete_comments(array('contextid'=>$context->id));
require_once($CFG->dirroot.'/rating/lib.php');
$delopt = new stdclass();
$delopt->contextid = $context->id;
$rm = new rating_manager();
$rm->delete_ratings($delopt);
// delete all files attached to this context
$fs = get_file_storage();
$fs->delete_area_files($context->id);
// now delete stuff from role related tables, role_unassign_all
// and unenrol should be called earlier to do proper cleanup
$DB->delete_records('role_assignments', array('contextid'=>$context->id));
$DB->delete_records('role_capabilities', array('contextid'=>$context->id));
$DB->delete_records('role_names', array('contextid'=>$context->id));
// and finally it is time to delete the context record if requested
if ($deleterecord) {
$DB->delete_records('context', array('id'=>$context->id));
// purge static context cache if entry present
$ACCESSLIB_PRIVATE->contexcache->remove($context);
}
// do not mark dirty contexts if parents unknown
if (!is_null($context->path) and $context->depth > 0) {
mark_context_dirty($context->path);
}
}
return true;
}
/**
* Precreates all contexts including all parents
*
* @param int $contextlevel empty means all
* @param bool $buildpaths update paths and depths
* @return void
*/
function create_contexts($contextlevel = null, $buildpaths = true) {
global $DB;
//make sure system context exists
$syscontext = get_system_context(false);
if (empty($contextlevel) or $contextlevel == CONTEXT_COURSECAT
or $contextlevel == CONTEXT_COURSE
or $contextlevel == CONTEXT_MODULE
or $contextlevel == CONTEXT_BLOCK) {
$sql = "INSERT INTO {context} (contextlevel, instanceid)
SELECT ".CONTEXT_COURSECAT.", cc.id
FROM {course}_categories cc
WHERE NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE cc.id = cx.instanceid AND cx.contextlevel=".CONTEXT_COURSECAT.")";
$DB->execute($sql);
}
if (empty($contextlevel) or $contextlevel == CONTEXT_COURSE
or $contextlevel == CONTEXT_MODULE
or $contextlevel == CONTEXT_BLOCK) {
$sql = "INSERT INTO {context} (contextlevel, instanceid)
SELECT ".CONTEXT_COURSE.", c.id
FROM {course} c
WHERE NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE c.id = cx.instanceid AND cx.contextlevel=".CONTEXT_COURSE.")";
$DB->execute($sql);
}
if (empty($contextlevel) or $contextlevel == CONTEXT_MODULE
or $contextlevel == CONTEXT_BLOCK) {
$sql = "INSERT INTO {context} (contextlevel, instanceid)
SELECT ".CONTEXT_MODULE.", cm.id
FROM {course}_modules cm
WHERE NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE cm.id = cx.instanceid AND cx.contextlevel=".CONTEXT_MODULE.")";
$DB->execute($sql);
}
if (empty($contextlevel) or $contextlevel == CONTEXT_USER
or $contextlevel == CONTEXT_BLOCK) {
$sql = "INSERT INTO {context} (contextlevel, instanceid)
SELECT ".CONTEXT_USER.", u.id
FROM {user} u
WHERE u.deleted=0
AND NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE u.id = cx.instanceid AND cx.contextlevel=".CONTEXT_USER.")";
$DB->execute($sql);
}
if (empty($contextlevel) or $contextlevel == CONTEXT_BLOCK) {
$sql = "INSERT INTO {context} (contextlevel, instanceid)
SELECT ".CONTEXT_BLOCK.", bi.id
FROM {block_instances} bi
WHERE NOT EXISTS (SELECT 'x'
FROM {context} cx
WHERE bi.id = cx.instanceid AND cx.contextlevel=".CONTEXT_BLOCK.")";
$DB->execute($sql);
}
if ($buildpaths) {
build_context_path(false);
}
}
/**
* Remove stale context records
*
* @return bool
*/
function cleanup_contexts() {
global $DB;
$sql = " SELECT c.contextlevel,
c.instanceid AS instanceid
FROM {context} c
LEFT OUTER JOIN {course}_categories t
ON c.instanceid = t.id
WHERE t.id IS NULL AND c.contextlevel = ".CONTEXT_COURSECAT."
UNION
SELECT c.contextlevel,
c.instanceid
FROM {context} c
LEFT OUTER JOIN {course} t
ON c.instanceid = t.id
WHERE t.id IS NULL AND c.contextlevel = ".CONTEXT_COURSE."
UNION
SELECT c.contextlevel,
c.instanceid
FROM {context} c
LEFT OUTER JOIN {course}_modules t
ON c.instanceid = t.id
WHERE t.id IS NULL AND c.contextlevel = ".CONTEXT_MODULE."
UNION
SELECT c.contextlevel,
c.instanceid
FROM {context} c
LEFT OUTER JOIN {user} t
ON c.instanceid = t.id
WHERE t.id IS NULL AND c.contextlevel = ".CONTEXT_USER."
UNION
SELECT c.contextlevel,
c.instanceid
FROM {context} c
LEFT OUTER JOIN {block_instances} t
ON c.instanceid = t.id
WHERE t.id IS NULL AND c.contextlevel = ".CONTEXT_BLOCK."
";
// transactions used only for performance reasons here
$transaction = $DB->start_delegated_transaction();
$rs = $DB->get_recordset_sql($sql);
foreach ($rs as $ctx) {
delete_context($ctx->contextlevel, $ctx->instanceid);
}
$rs->close();
$transaction->allow_commit();
return true;
}
/**
* Preloads all contexts relating to a course: course, modules. Block contexts
* are no longer loaded here. The contexts for all the blocks on the current
* page are now efficiently loaded by {@link block_manager::load_blocks()}.
*
* @param int $courseid Course ID
* @return void
*/
function preload_course_contexts($courseid) {
global $DB, $ACCESSLIB_PRIVATE;
// Users can call this multiple times without doing any harm
global $ACCESSLIB_PRIVATE;
if (array_key_exists($courseid, $ACCESSLIB_PRIVATE->preloadedcourses)) {
return;
}
$params = array($courseid, $courseid, $courseid);
$sql = "SELECT x.instanceid, x.id, x.contextlevel, x.path, x.depth
FROM {course_modules} cm
JOIN {context} x ON x.instanceid=cm.id
WHERE cm.course=? AND x.contextlevel=".CONTEXT_MODULE."
UNION ALL
SELECT x.instanceid, x.id, x.contextlevel, x.path, x.depth
FROM {context} x
WHERE x.instanceid=? AND x.contextlevel=".CONTEXT_COURSE."";
$rs = $DB->get_recordset_sql($sql, $params);
foreach($rs as $context) {
$ACCESSLIB_PRIVATE->contexcache->add($context);
}
$rs->close();
$ACCESSLIB_PRIVATE->preloadedcourses[$courseid] = true;
}
/**
* Get the context instance as an object. This function will create the
* context instance if it does not exist yet.
*
* @todo Remove code branch from previous fix MDL-9016 which is no longer needed
*
* @param integer $level The context level, for example CONTEXT_COURSE, or CONTEXT_MODULE.
* @param integer $instance The instance id. For $level = CONTEXT_COURSE, this would be $course->id,
* for $level = CONTEXT_MODULE, this would be $cm->id. And so on. Defaults to 0
* @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
* MUST_EXIST means throw exception if no record or multiple records found
* @return object The context object.
*/
function get_context_instance($contextlevel, $instance = 0, $strictness = IGNORE_MISSING) {
global $DB, $ACCESSLIB_PRIVATE;
static $allowed_contexts = array(CONTEXT_SYSTEM, CONTEXT_USER, CONTEXT_COURSECAT, CONTEXT_COURSE, CONTEXT_MODULE, CONTEXT_BLOCK);
/// System context has special cache
if ($contextlevel == CONTEXT_SYSTEM) {
return get_system_context();
}
/// check allowed context levels
if (!in_array($contextlevel, $allowed_contexts)) {
// fatal error, code must be fixed - probably typo or switched parameters
print_error('invalidcourselevel');
}
// Various operations rely on context cache
$cache = $ACCESSLIB_PRIVATE->contexcache;
if (!is_array($instance)) {
/// Check the cache
$context = $cache->get($contextlevel, $instance);
if ($context) {
return $context;
}
/// Get it from the database, or create it
if (!$context = $DB->get_record('context', array('contextlevel'=>$contextlevel, 'instanceid'=>$instance))) {
$context = create_context($contextlevel, $instance, $strictness);
}
/// Only add to cache if context isn't empty.
if (!empty($context)) {
$cache->add($context);
}
return $context;
}
/// ok, somebody wants to load several contexts to save some db queries ;-)
$instances = $instance;
$result = array();
foreach ($instances as $key=>$instance) {
/// Check the cache first
if ($context = $cache->get($contextlevel, $instance)) { // Already cached
$result[$instance] = $context;
unset($instances[$key]);
continue;
}
}
if ($instances) {
list($instanceids, $params) = $DB->get_in_or_equal($instances, SQL_PARAMS_QM);
array_unshift($params, $contextlevel);
$sql = "SELECT instanceid, id, contextlevel, path, depth
FROM {context}
WHERE contextlevel=? AND instanceid $instanceids";
if (!$contexts = $DB->get_records_sql($sql, $params)) {
$contexts = array();
}
foreach ($instances as $instance) {
if (isset($contexts[$instance])) {
$context = $contexts[$instance];
} else {
$context = create_context($contextlevel, $instance);
}
if (!empty($context)) {
$cache->add($context);
}
$result[$instance] = $context;
}
}
return $result;
}
/**
* Get a context instance as an object, from a given context id.
*
* @param int $id context id
* @param int $strictness IGNORE_MISSING means compatible mode, false returned if record not found, debug message if more found;
* MUST_EXIST means throw exception if no record or multiple records found
* @return stdClass|bool the context object or false if not found.
*/
function get_context_instance_by_id($id, $strictness = IGNORE_MISSING) {
global $DB, $ACCESSLIB_PRIVATE;
if ($id == SYSCONTEXTID) {
return get_system_context();
}
$cache = $ACCESSLIB_PRIVATE->contexcache;
if ($context = $cache->get_by_id($id)) {
return $context;
}
if ($context = $DB->get_record('context', array('id'=>$id), '*', $strictness)) {
$cache->add($context);
return $context;
}
return false;
}
/**
* Get the local override (if any) for a given capability in a role in a context
*
* @param int $roleid
* @param int $contextid
* @param string $capability
*/
function get_local_override($roleid, $contextid, $capability) {
global $DB;
return $DB->get_record('role_capabilities', array('roleid'=>$roleid, 'capability'=>$capability, 'contextid'=>$contextid));
}
/**
* Returns context instance plus related course and cm instances
* @param int $contextid
* @return array of ($context, $course, $cm)
*/
function get_context_info_array($contextid) {
global $DB;
$context = get_context_instance_by_id($contextid, MUST_EXIST);
$course = null;
$cm = null;
if ($context->contextlevel == CONTEXT_COURSE) {
$course = $DB->get_record('course', array('id'=>$context->instanceid), '*', MUST_EXIST);
} else if ($context->contextlevel == CONTEXT_MODULE) {
$cm = get_coursemodule_from_id('', $context->instanceid, 0, false, MUST_EXIST);
$course = $DB->get_record('course', array('id'=>$cm->course), '*', MUST_EXIST);
} else if ($context->contextlevel == CONTEXT_BLOCK) {
$parentcontexts = get_parent_contexts($context, false);
$parent = reset($parentcontexts);
$parent = get_context_instance_by_id($parent);
if ($parent->contextlevel == CONTEXT_COURSE) {
$course = $DB->get_record('course', array('id'=>$parent->instanceid), '*', MUST_EXIST);
} else if ($parent->contextlevel == CONTEXT_MODULE) {
$cm = get_coursemodule_from_id('', $parent->instanceid, 0, false, MUST_EXIST);
$course = $DB->get_record('course', array('id'=>$cm->course), '*', MUST_EXIST);
}
}
return array($context, $course, $cm);
}
/**
* Returns current course id or null if outside of course based on context parameter.
* @param object $context
* @return int|bool related course id or false
*/
function get_courseid_from_context($context) {
if (empty($context->contextlevel)) {
debugging('Invalid context object specified in get_courseid_from_context() call');
return false;
}
if ($context->contextlevel == CONTEXT_COURSE) {
return $context->instanceid;
}
if ($context->contextlevel < CONTEXT_COURSE) {
return false;
}
if ($context->contextlevel == CONTEXT_MODULE) {
$parentcontexts = get_parent_contexts($context, false);
$parent = reset($parentcontexts);
$parent = get_context_instance_by_id($parent);
return $parent->instanceid;
}
if ($context->contextlevel == CONTEXT_BLOCK) {
$parentcontexts = get_parent_contexts($context, false);
$parent = reset($parentcontexts);
return get_courseid_from_context(get_context_instance_by_id($parent));
}
return false;
}
//////////////////////////////////////
// DB TABLE RELATED FUNCTIONS //
//////////////////////////////////////
/**
* function that creates a role
*
* @param string $name role name
* @param string $shortname role short name
* @param string $description role description
* @param string $archetype
* @return int id or dml_exception
*/
function create_role($name, $shortname, $description, $archetype = '') {
global $DB;
if (strpos($archetype, 'moodle/legacy:') !== false) {
throw new coding_exception('Use new role archetype parameter in create_role() instead of old legacy capabilities.');
}
// verify role archetype actually exists
$archetypes = get_role_archetypes();
if (empty($archetypes[$archetype])) {
$archetype = '';
}
// Get the system context.
$context = get_context_instance(CONTEXT_SYSTEM);
// Insert the role record.
$role = new stdClass();
$role->name = $name;
$role->shortname = $shortname;
$role->description = $description;
$role->archetype = $archetype;
//find free sortorder number
$role->sortorder = $DB->get_field('role', 'MAX(sortorder) + 1', array());
if (empty($role->sortorder)) {
$role->sortorder = 1;
}
$id = $DB->insert_record('role', $role);
return $id;
}
/**
* Function that deletes a role and cleanups up after it
*
* @param int $roleid id of role to delete
* @return bool always true
*/
function delete_role($roleid) {
global $CFG, $DB;
// first unssign all users
role_unassign_all(array('roleid'=>$roleid));
// cleanup all references to this role, ignore errors
$DB->delete_records('role_capabilities', array('roleid'=>$roleid));
$DB->delete_records('role_allow_assign', array('roleid'=>$roleid));
$DB->delete_records('role_allow_assign', array('allowassign'=>$roleid));
$DB->delete_records('role_allow_override', array('roleid'=>$roleid));
$DB->delete_records('role_allow_override', array('allowoverride'=>$roleid));
$DB->delete_records('role_names', array('roleid'=>$roleid));
$DB->delete_records('role_context_levels', array('roleid'=>$roleid));
// finally delete the role itself
// get this before the name is gone for logging
$rolename = $DB->get_field('role', 'name', array('id'=>$roleid));
$DB->delete_records('role', array('id'=>$roleid));
add_to_log(SITEID, 'role', 'delete', 'admin/roles/action=delete&roleid='.$roleid, $rolename, '');
return true;
}
/**
* Function to write context specific overrides, or default capabilities.
*
* @param string $capability string name
* @param int $permission CAP_ constants
* @param int $roleid role id
* @param int $contextid context id
* @param bool $overwrite
* @return bool always true or exception
*/
function assign_capability($capability, $permission, $roleid, $contextid, $overwrite = false) {
global $USER, $DB;
if (empty($permission) || $permission == CAP_INHERIT) { // if permission is not set
unassign_capability($capability, $roleid, $contextid);
return true;
}
$existing = $DB->get_record('role_capabilities', array('contextid'=>$contextid, 'roleid'=>$roleid, 'capability'=>$capability));
if ($existing and !$overwrite) { // We want to keep whatever is there already
return true;
}
$cap = new stdClass();
$cap->contextid = $contextid;
$cap->roleid = $roleid;
$cap->capability = $capability;
$cap->permission = $permission;
$cap->timemodified = time();
$cap->modifierid = empty($USER->id) ? 0 : $USER->id;
if ($existing) {
$cap->id = $existing->id;
$DB->update_record('role_capabilities', $cap);
} else {
$c = $DB->get_record('context', array('id'=>$contextid));
$DB->insert_record('role_capabilities', $cap);
}
return true;
}
/**
* Unassign a capability from a role.
*
* @param string $capability the name of the capability
* @param int $roleid the role id
* @param int $contextid null means all contexts
* @return boolean success or failure
*/
function unassign_capability($capability, $roleid, $contextid = null) {
global $DB;
if (!empty($contextid)) {
// delete from context rel, if this is the last override in this context
$DB->delete_records('role_capabilities', array('capability'=>$capability, 'roleid'=>$roleid, 'contextid'=>$contextid));
} else {
$DB->delete_records('role_capabilities', array('capability'=>$capability, 'roleid'=>$roleid));
}
return true;
}
/**
* Get the roles that have a given capability assigned to it
*
* This function does not resolve the actual permission of the capability.
* It just checks for permissions and overrides.
* Use get_roles_with_cap_in_context() if resolution is required.
*
* @param string $capability - capability name (string)
* @param string $permission - optional, the permission defined for this capability
* either CAP_ALLOW, CAP_PREVENT or CAP_PROHIBIT. Defaults to null which means any.
* @param stdClass $context, null means any
* @return array of role objects
*/
function get_roles_with_capability($capability, $permission = null, $context = null) {
global $DB;
if ($context) {
$contexts = get_parent_contexts($context, true);
list($insql, $params) = $DB->get_in_or_equal($contexts, SQL_PARAMS_NAMED, 'ctx');
$contextsql = "AND rc.contextid $insql";
} else {
$params = array();
$contextsql = '';
}
if ($permission) {
$permissionsql = " AND rc.permission = :permission";
$params['permission'] = $permission;
} else {
$permissionsql = '';
}
$sql = "SELECT r.*
FROM {role} r
WHERE r.id IN (SELECT rc.roleid
FROM {role_capabilities} rc
WHERE rc.capability = :capname
$contextsql
$permissionsql)";
$params['capname'] = $capability;
return $DB->get_records_sql($sql, $params);
}
/**
* This function makes a role-assignment (a role for a user in a particular context)
*
* @param int $roleid the role of the id
* @param int $userid userid
* @param int $contextid id of the context
* @param string $component example 'enrol_ldap', defaults to '' which means manual assignment,
* @prama int $itemid id of enrolment/auth plugin
* @param string $timemodified defaults to current time
* @return int new/existing id of the assignment
*/
function role_assign($roleid, $userid, $contextid, $component = '', $itemid = 0, $timemodified = '') {
global $USER, $CFG, $DB;
// first of all detect if somebody is using old style parameters
if ($contextid === 0 or is_numeric($component)) {
throw new coding_exception('Invalid call to role_assign(), code needs to be updated to use new order of parameters');
}
// now validate all parameters
if (empty($roleid)) {
throw new coding_exception('Invalid call to role_assign(), roleid can not be empty');
}
if (empty($userid)) {
throw new coding_exception('Invalid call to role_assign(), userid can not be empty');
}
if ($itemid) {
if (strpos($component, '_') === false) {
throw new coding_exception('Invalid call to role_assign(), component must start with plugin type such as"enrol_" when itemid specified', 'component:'.$component);
}
} else {
$itemid = 0;
if ($component !== '' and strpos($component, '_') === false) {
throw new coding_exception('Invalid call to role_assign(), invalid component string', 'component:'.$component);
}
}
if (!$DB->record_exists('user', array('id'=>$userid, 'deleted'=>0))) {
throw new coding_exception('User ID does not exist or is deleted!', 'userid:'.$userid);
}
$context = get_context_instance_by_id($contextid, MUST_EXIST);
if (!$timemodified) {
$timemodified = time();
}
/// Check for existing entry
$ras = $DB->get_records('role_assignments', array('roleid'=>$roleid, 'contextid'=>$context->id, 'userid'=>$userid, 'component'=>$component, 'itemid'=>$itemid), 'id');
if ($ras) {
// role already assigned - this should not happen
if (count($ras) > 1) {
//very weird - remove all duplicates!
$ra = array_shift($ras);
foreach ($ras as $r) {
$DB->delete_records('role_assignments', array('id'=>$r->id));
}
} else {
$ra = reset($ras);
}
// actually there is no need to update, reset anything or trigger any event, so just return
return $ra->id;
}
// Create a new entry
$ra = new stdClass();
$ra->roleid = $roleid;
$ra->contextid = $context->id;
$ra->userid = $userid;
$ra->component = $component;
$ra->itemid = $itemid;
$ra->timemodified = $timemodified;
$ra->modifierid = empty($USER->id) ? 0 : $USER->id;
$ra->id = $DB->insert_record('role_assignments', $ra);
// mark context as dirty - again expensive, but needed
mark_context_dirty($context->path);
if (!empty($USER->id) && $USER->id == $userid) {
// If the user is the current user, then do full reload of capabilities too.
load_all_capabilities();
}
events_trigger('role_assigned', $ra);
return $ra->id;
}
/**
* Removes one role assignment
*
* @param int $roleid
* @param int $userid
* @param int $contextid
* @param string $component
* @param int $itemid
* @return void
*/
function role_unassign($roleid, $userid, $contextid, $component = '', $itemid = 0) {
global $USER, $CFG, $DB;
// first make sure the params make sense
if ($roleid == 0 or $userid == 0 or $contextid == 0) {
throw new coding_exception('Invalid call to role_unassign(), please use role_unassign_all() when removing multiple role assignments');
}
if ($itemid) {
if (strpos($component, '_') === false) {
throw new coding_exception('Invalid call to role_assign(), component must start with plugin type such as "enrol_" when itemid specified', 'component:'.$component);
}
} else {
$itemid = 0;
if ($component !== '' and strpos($component, '_') === false) {
throw new coding_exception('Invalid call to role_assign(), invalid component string', 'component:'.$component);
}
}
role_unassign_all(array('roleid'=>$roleid, 'userid'=>$userid, 'contextid'=>$contextid, 'component'=>$component, 'itemid'=>$itemid), false, false);
}
/**
* Removes multiple role assignments, parameters may contain:
* 'roleid', 'userid', 'contextid', 'component', 'enrolid'.
*
* @param array $params role assignment parameters
* @param bool $subcontexts unassign in subcontexts too
* @param bool $includmanual include manual role assignments too
* @return void
*/
function role_unassign_all(array $params, $subcontexts = false, $includemanual = false) {
global $USER, $CFG, $DB;
if (!$params) {
throw new coding_exception('Missing parameters in role_unsassign_all() call');
}
$allowed = array('roleid', 'userid', 'contextid', 'component', 'itemid');
foreach ($params as $key=>$value) {
if (!in_array($key, $allowed)) {
throw new coding_exception('Unknown role_unsassign_all() parameter key', 'key:'.$key);
}
}
if (isset($params['component']) and $params['component'] !== '' and strpos($params['component'], '_') === false) {
throw new coding_exception('Invalid component paramter in role_unsassign_all() call', 'component:'.$params['component']);
}
if ($includemanual) {
if (!isset($params['component']) or $params['component'] === '') {
throw new coding_exception('include manual parameter requires component parameter in role_unsassign_all() call');
}
}
if ($subcontexts) {
if (empty($params['contextid'])) {
throw new coding_exception('subcontexts paramtere requires component parameter in role_unsassign_all() call');
}
}
$ras = $DB->get_records('role_assignments', $params);
foreach($ras as $ra) {
$DB->delete_records('role_assignments', array('id'=>$ra->id));
if ($context = get_context_instance_by_id($ra->contextid)) {
// this is a bit expensive but necessary
mark_context_dirty($context->path);
/// If the user is the current user, then do full reload of capabilities too.
if (!empty($USER->id) && $USER->id == $ra->userid) {
load_all_capabilities();
}
}
events_trigger('role_unassigned', $ra);
}
unset($ras);
// process subcontexts
if ($subcontexts and $context = get_context_instance_by_id($params['contextid'])) {
$contexts = get_child_contexts($context);
$mparams = $params;
foreach($contexts as $context) {
$mparams['contextid'] = $context->id;
$ras = $DB->get_records('role_assignments', $mparams);
foreach($ras as $ra) {
$DB->delete_records('role_assignments', array('id'=>$ra->id));
// this is a bit expensive but necessary
mark_context_dirty($context->path);
/// If the user is the current user, then do full reload of capabilities too.
if (!empty($USER->id) && $USER->id == $ra->userid) {
load_all_capabilities();
}
events_trigger('role_unassigned', $ra);
}
}
}
// do this once more for all manual role assignments
if ($includemanual) {
$params['component'] = '';
role_unassign_all($params, $subcontexts, false);
}
}
/**
* Determines if a user is currently logged in
*
* @return bool
*/
function isloggedin() {
global $USER;
return (!empty($USER->id));
}
/**
* Determines if a user is logged in as real guest user with username 'guest'.
*
* @param int|object $user mixed user object or id, $USER if not specified
* @return bool true if user is the real guest user, false if not logged in or other user
*/
function isguestuser($user = null) {
global $USER, $DB, $CFG;
// make sure we have the user id cached in config table, because we are going to use it a lot
if (empty($CFG->siteguest)) {
if (!$guestid = $DB->get_field('user', 'id', array('username'=>'guest', 'mnethostid'=>$CFG->mnet_localhost_id))) {
// guest does not exist yet, weird
return false;
}
set_config('siteguest', $guestid);
}
if ($user === null) {
$user = $USER;
}
if ($user === null) {
// happens when setting the $USER
return false;
} else if (is_numeric($user)) {
return ($CFG->siteguest == $user);
} else if (is_object($user)) {
if (empty($user->id)) {
return false; // not logged in means is not be guest
} else {
return ($CFG->siteguest == $user->id);
}
} else {
throw new coding_exception('Invalid user parameter supplied for isguestuser() function!');
}
}
/**
* Does user have a (temporary or real) guest access to course?
*
* @param stdClass $context
* @param stdClass|int $user
* @return bool
*/
function is_guest($context, $user = null) {
global $USER;
// first find the course context
$coursecontext = get_course_context($context);
// make sure there is a real user specified
if ($user === null) {
$userid = isset($USER->id) ? $USER->id : 0;
} else {
$userid = is_object($user) ? $user->id : $user;
}
if (isguestuser($userid)) {
// can not inspect or be enrolled
return true;
}
if (has_capability('moodle/course:view', $coursecontext, $user)) {
// viewing users appear out of nowhere, they are neither guests nor participants
return false;
}
// consider only real active enrolments here
if (is_enrolled($coursecontext, $user, '', true)) {
return false;
}
return true;
}
/**
* Returns true if the user has moodle/course:view capability in the course,
* this is intended for admins, managers (aka small admins), inspectors, etc.
*
* @param stdClass $context
* @param int|object $user, if null $USER is used
* @param string $withcapability extra capability name
* @return bool
*/
function is_viewing($context, $user = null, $withcapability = '') {
// first find the course context
$coursecontext = get_course_context($context);
if (isguestuser($user)) {
// can not inspect
return false;
}
if (!has_capability('moodle/course:view', $coursecontext, $user)) {
// admins are allowed to inspect courses
return false;
}
if ($withcapability and !has_capability($withcapability, $context, $user)) {
// site admins always have the capability, but the enrolment above blocks
return false;
}
return true;
}
/**
* Returns true if user is enrolled (is participating) in course
* this is intended for students and teachers.
*
* @param object $context
* @param int|object $user, if null $USER is used, otherwise user object or id expected
* @param string $withcapability extra capability name
* @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
* @return bool
*/
function is_enrolled($context, $user = null, $withcapability = '', $onlyactive = false) {
global $USER, $DB;
// first find the course context
$coursecontext = get_course_context($context);
// make sure there is a real user specified
if ($user === null) {
$userid = isset($USER->id) ? $USER->id : 0;
} else {
$userid = is_object($user) ? $user->id : $user;
}
if (empty($userid)) {
// not-logged-in!
return false;
} else if (isguestuser($userid)) {
// guest account can not be enrolled anywhere
return false;
}
if ($coursecontext->instanceid == SITEID) {
// everybody participates on frontpage
} else {
if ($onlyactive) {
$sql = "SELECT ue.*
FROM {user_enrolments} ue
JOIN {enrol} e ON (e.id = ue.enrolid AND e.courseid = :courseid)
JOIN {user} u ON u.id = ue.userid
WHERE ue.userid = :userid AND ue.status = :active AND e.status = :enabled AND u.deleted = 0";
$params = array('enabled'=>ENROL_INSTANCE_ENABLED, 'active'=>ENROL_USER_ACTIVE, 'userid'=>$userid, 'courseid'=>$coursecontext->instanceid);
// this result should be very small, better not do the complex time checks in sql for now ;-)
$enrolments = $DB->get_records_sql($sql, $params);
$now = time();
// make sure the enrol period is ok
$result = false;
foreach ($enrolments as $e) {
if ($e->timestart > $now) {
continue;
}
if ($e->timeend and $e->timeend < $now) {
continue;
}
$result = true;
break;
}
if (!$result) {
return false;
}
} else {
// any enrolment is good for us here, even outdated, disabled or inactive
$sql = "SELECT 'x'
FROM {user_enrolments} ue
JOIN {enrol} e ON (e.id = ue.enrolid AND e.courseid = :courseid)
JOIN {user} u ON u.id = ue.userid
WHERE ue.userid = :userid AND u.deleted = 0";
$params = array('userid'=>$userid, 'courseid'=>$coursecontext->instanceid);
if (!$DB->record_exists_sql($sql, $params)) {
return false;
}
}
}
if ($withcapability and !has_capability($withcapability, $context, $userid)) {
return false;
}
return true;
}
/**
* Returns true if the user is able to access the course.
*
* This function is in no way, shape, or form a substitute for require_login.
* It should only be used in circumstances where it is not possible to call require_login
* such as the navigation.
*
* This function checks many of the methods of access to a course such as the view
* capability, enrollments, and guest access. It also makes use of the cache
* generated by require_login for guest access.
*
* The flags within the $USER object that are used here should NEVER be used outside
* of this function can_access_course and require_login. Doing so WILL break future
* versions.
*
* @global moodle_database $DB
* @param stdClass $context
* @param stdClass|null $user
* @param string $withcapability Check for this capability as well.
* @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
* @param boolean $trustcache If set to false guest access will always be checked
* against the enrolment plugins from the course, rather
* than the cache generated by require_login.
* @return boolean Returns true if the user is able to access the course
*/
function can_access_course($context, $user = null, $withcapability = '', $onlyactive = false, $trustcache = true) {
global $DB, $USER;
$coursecontext = get_course_context($context);
$courseid = $coursecontext->instanceid;
// First check the obvious, is the user viewing or is the user enrolled.
if (is_viewing($coursecontext, $user, $withcapability) || is_enrolled($coursecontext, $user, $withcapability, $onlyactive)) {
// How easy was that!
return true;
}
$access = false;
if (!isset($USER->enrol)) {
// Cache hasn't been generated yet so we can't trust it
$trustcache = false;
/**
* These flags within the $USER object should NEVER be used outside of this
* function can_access_course and the function require_login.
* Doing so WILL break future versions!!!!
*/
$USER->enrol = array();
$USER->enrol['enrolled'] = array();
$USER->enrol['tempguest'] = array();
}
// If we don't trust the cache we need to check with the courses enrolment
// plugin instances to see if the user can access the course as a guest.
if (!$trustcache) {
// Ok, off to the database we go!
$instances = $DB->get_records('enrol', array('courseid'=>$courseid, 'status'=>ENROL_INSTANCE_ENABLED), 'sortorder, id ASC');
$enrols = enrol_get_plugins(true);
foreach($instances as $instance) {
if (!isset($enrols[$instance->enrol])) {
continue;
}
$until = $enrols[$instance->enrol]->try_guestaccess($instance);
if ($until !== false) {
// Never use me anywhere but here and require_login
$USER->enrol['tempguest'][$courseid] = $until;
$access = true;
break;
}
}
}
// If we don't already have access (from above) check the cache and see whether
// there is record of it in there.
if (!$access && isset($USER->enrol['tempguest'][$courseid])) {
// Never use me anywhere but here and require_login
if ($USER->enrol['tempguest'][$courseid] == 0) {
$access = true;
} else if ($USER->enrol['tempguest'][$courseid] > time()) {
$access = true;
} else {
//expired
unset($USER->enrol['tempguest'][$courseid]);
}
}
return $access;
}
/**
* Returns array with sql code and parameters returning all ids
* of users enrolled into course.
*
* This function is using 'eu[0-9]+_' prefix for table names and parameters.
*
* @param object $context
* @param string $withcapability
* @param int $groupid 0 means ignore groups, any other value limits the result by group id
* @param bool $onlyactive consider only active enrolments in enabled plugins and time restrictions
* @return array list($sql, $params)
*/
function get_enrolled_sql($context, $withcapability = '', $groupid = 0, $onlyactive = false) {
global $DB, $CFG;
// use unique prefix just in case somebody makes some SQL magic with the result
static $i = 0;
$i++;
$prefix = 'eu'.$i.'_';
// first find the course context
$coursecontext = get_course_context($context);
$isfrontpage = ($coursecontext->instanceid == SITEID);
$joins = array();
$wheres = array();
$params = array();
list($contextids, $contextpaths) = get_context_info_list($context);
// get all relevant capability info for all roles
if ($withcapability) {
list($incontexts, $cparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED, 'ctx');
$cparams['cap'] = $withcapability;
$defs = array();
$sql = "SELECT rc.id, rc.roleid, rc.permission, ctx.path
FROM {role_capabilities} rc
JOIN {context} ctx on rc.contextid = ctx.id
WHERE rc.contextid $incontexts AND rc.capability = :cap";
$rcs = $DB->get_records_sql($sql, $cparams);
foreach ($rcs as $rc) {
$defs[$rc->path][$rc->roleid] = $rc->permission;
}
$access = array();
if (!empty($defs)) {
foreach ($contextpaths as $path) {
if (empty($defs[$path])) {
continue;
}
foreach($defs[$path] as $roleid => $perm) {
if ($perm == CAP_PROHIBIT) {
$access[$roleid] = CAP_PROHIBIT;
continue;
}
if (!isset($access[$roleid])) {
$access[$roleid] = (int)$perm;
}
}
}
}
unset($defs);
// make lists of roles that are needed and prohibited
$needed = array(); // one of these is enough
$prohibited = array(); // must not have any of these
foreach ($access as $roleid => $perm) {
if ($perm == CAP_PROHIBIT) {
unset($needed[$roleid]);
$prohibited[$roleid] = true;
} else if ($perm == CAP_ALLOW and empty($prohibited[$roleid])) {
$needed[$roleid] = true;
}
}
$defaultuserroleid = isset($CFG->defaultuserroleid) ? $CFG->defaultuserroleid : 0;
$defaultfrontpageroleid = isset($CFG->defaultfrontpageroleid) ? $CFG->defaultfrontpageroleid : 0;
$nobody = false;
if ($isfrontpage) {
if (!empty($prohibited[$defaultuserroleid]) or !empty($prohibited[$defaultfrontpageroleid])) {
$nobody = true;
} else if (!empty($needed[$defaultuserroleid]) or !empty($needed[$defaultfrontpageroleid])) {
// everybody not having prohibit has the capability
$needed = array();
} else if (empty($needed)) {
$nobody = true;
}
} else {
if (!empty($prohibited[$defaultuserroleid])) {
$nobody = true;
} else if (!empty($needed[$defaultuserroleid])) {
// everybody not having prohibit has the capability
$needed = array();
} else if (empty($needed)) {
$nobody = true;
}
}
if ($nobody) {
// nobody can match so return some SQL that does not return any results
$wheres[] = "1 = 2";
} else {
if ($needed) {
$ctxids = implode(',', $contextids);
$roleids = implode(',', array_keys($needed));
$joins[] = "JOIN {role_assignments} {$prefix}ra3 ON ({$prefix}ra3.userid = {$prefix}u.id AND {$prefix}ra3.roleid IN ($roleids) AND {$prefix}ra3.contextid IN ($ctxids))";
}
if ($prohibited) {
$ctxids = implode(',', $contextids);
$roleids = implode(',', array_keys($prohibited));
$joins[] = "LEFT JOIN {role_assignments} {$prefix}ra4 ON ({$prefix}ra4.userid = {$prefix}u.id AND {$prefix}ra4.roleid IN ($roleids) AND {$prefix}ra4.contextid IN ($ctxids))";
$wheres[] = "{$prefix}ra4.id IS NULL";
}
if ($groupid) {
$joins[] = "JOIN {groups_members} {$prefix}gm ON ({$prefix}gm.userid = {$prefix}u.id AND {$prefix}gm.groupid = :{$prefix}gmid)";
$params["{$prefix}gmid"] = $groupid;
}
}
} else {
if ($groupid) {
$joins[] = "JOIN {groups_members} {$prefix}gm ON ({$prefix}gm.userid = {$prefix}u.id AND {$prefix}gm.groupid = :{$prefix}gmid)";
$params["{$prefix}gmid"] = $groupid;
}
}
$wheres[] = "{$prefix}u.deleted = 0 AND {$prefix}u.id <> :{$prefix}guestid";
$params["{$prefix}guestid"] = $CFG->siteguest;
if ($isfrontpage) {
// all users are "enrolled" on the frontpage
} else {
$joins[] = "JOIN {user_enrolments} {$prefix}ue ON {$prefix}ue.userid = {$prefix}u.id";
$joins[] = "JOIN {enrol} {$prefix}e ON ({$prefix}e.id = {$prefix}ue.enrolid AND {$prefix}e.courseid = :{$prefix}courseid)";
$params[$prefix.'courseid'] = $coursecontext->instanceid;
if ($onlyactive) {
$wheres[] = "{$prefix}ue.status = :{$prefix}active AND {$prefix}e.status = :{$prefix}enabled";
$wheres[] = "{$prefix}ue.timestart < :{$prefix}now1 AND ({$prefix}ue.timeend = 0 OR {$prefix}ue.timeend > :{$prefix}now2)";
$now = round(time(), -2); // rounding helps caching in DB
$params = array_merge($params, array($prefix.'enabled'=>ENROL_INSTANCE_ENABLED,
$prefix.'active'=>ENROL_USER_ACTIVE,
$prefix.'now1'=>$now, $prefix.'now2'=>$now));
}
}
$joins = implode("\n", $joins);
$wheres = "WHERE ".implode(" AND ", $wheres);
$sql = "SELECT DISTINCT {$prefix}u.id
FROM {user} {$prefix}u
$joins
$wheres";
return array($sql, $params);
}
/**
* Returns list of users enrolled into course.
* @param object $context
* @param string $withcapability
* @param int $groupid 0 means ignore groups, any other value limits the result by group id
* @param string $userfields requested user record fields
* @param string $orderby
* @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
* @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
* @return array of user records
*/
function get_enrolled_users($context, $withcapability = '', $groupid = 0, $userfields = 'u.*', $orderby = '', $limitfrom = 0, $limitnum = 0) {
global $DB;
list($esql, $params) = get_enrolled_sql($context, $withcapability, $groupid);
$sql = "SELECT $userfields
FROM {user} u
JOIN ($esql) je ON je.id = u.id
WHERE u.deleted = 0";
if ($orderby) {
$sql = "$sql ORDER BY $orderby";
} else {
$sql = "$sql ORDER BY u.lastname ASC, u.firstname ASC";
}
return $DB->get_records_sql($sql, $params, $limitfrom, $limitnum);
}
/**
* Counts list of users enrolled into course (as per above function)
* @param object $context
* @param string $withcapability
* @param int $groupid 0 means ignore groups, any other value limits the result by group id
* @return array of user records
*/
function count_enrolled_users($context, $withcapability = '', $groupid = 0) {
global $DB;
list($esql, $params) = get_enrolled_sql($context, $withcapability, $groupid);
$sql = "SELECT count(u.id)
FROM {user} u
JOIN ($esql) je ON je.id = u.id
WHERE u.deleted = 0";
return $DB->count_records_sql($sql, $params);
}
/**
* Loads the capability definitions for the component (from file).
*
* Loads the capability definitions for the component (from file). If no
* capabilities are defined for the component, we simply return an empty array.
*
* @param string $component full plugin name, examples: 'moodle', 'mod_forum'
* @return array array of capabilities
*/
function load_capability_def($component) {
$defpath = get_component_directory($component).'/db/access.php';
$capabilities = array();
if (file_exists($defpath)) {
require($defpath);
if (!empty(${$component.'_capabilities'})) {
// BC capability array name
// since 2.0 we prefer $capabilities instead - it is easier to use and matches db/* files
debugging('componentname_capabilities array is deprecated, please use capabilities array only in access.php files');
$capabilities = ${$component.'_capabilities'};
}
}
return $capabilities;
}
/**
* Gets the capabilities that have been cached in the database for this component.
* @param string $component - examples: 'moodle', 'mod_forum'
* @return array array of capabilities
*/
function get_cached_capabilities($component = 'moodle') {
global $DB;
return $DB->get_records('capabilities', array('component'=>$component));
}
/**
* Returns default capabilities for given role archetype.
* @param string $archetype role archetype
* @return array
*/
function get_default_capabilities($archetype) {
global $DB;
if (!$archetype) {
return array();
}
$alldefs = array();
$defaults = array();
$components = array();
$allcaps = $DB->get_records('capabilities');
foreach ($allcaps as $cap) {
if (!in_array($cap->component, $components)) {
$components[] = $cap->component;
$alldefs = array_merge($alldefs, load_capability_def($cap->component));
}
}
foreach($alldefs as $name=>$def) {
// Use array 'archetypes if available. Only if not specified, use 'legacy'.
if (isset($def['archetypes'])) {
if (isset($def['archetypes'][$archetype])) {
$defaults[$name] = $def['archetypes'][$archetype];
}
// 'legacy' is for backward compatibility with 1.9 access.php
} else {
if (isset($def['legacy'][$archetype])) {
$defaults[$name] = $def['legacy'][$archetype];
}
}
}
return $defaults;
}
/**
* Reset role capabilities to default according to selected role archetype.
* If no archetype selected, removes all capabilities.
* @param int $roleid
* @return void
*/
function reset_role_capabilities($roleid) {
global $DB;
$role = $DB->get_record('role', array('id'=>$roleid), '*', MUST_EXIST);
$defaultcaps = get_default_capabilities($role->archetype);
$sitecontext = get_context_instance(CONTEXT_SYSTEM);
$DB->delete_records('role_capabilities', array('roleid'=>$roleid));
foreach($defaultcaps as $cap=>$permission) {
assign_capability($cap, $permission, $roleid, $sitecontext->id);
}
}
/**
* Updates the capabilities table with the component capability definitions.
* If no parameters are given, the function updates the core moodle
* capabilities.
*
* Note that the absence of the db/access.php capabilities definition file
* will cause any stored capabilities for the component to be removed from
* the database.
*
* @param string $component examples: 'moodle', 'mod/forum', 'block/quiz_results'
* @return boolean true if success, exception in case of any problems
*/
function update_capabilities($component = 'moodle') {
global $DB, $OUTPUT, $ACCESSLIB_PRIVATE;
$storedcaps = array();
$filecaps = load_capability_def($component);
foreach($filecaps as $capname=>$unused) {
if (!preg_match('|^[a-z]+/[a-z_0-9]+:[a-z_0-9]+$|', $capname)) {
debugging("Coding problem: Invalid capability name '$capname', use 'clonepermissionsfrom' field for migration.");
}
}
$cachedcaps = get_cached_capabilities($component);
if ($cachedcaps) {
foreach ($cachedcaps as $cachedcap) {
array_push($storedcaps, $cachedcap->name);
// update risk bitmasks and context levels in existing capabilities if needed
if (array_key_exists($cachedcap->name, $filecaps)) {
if (!array_key_exists('riskbitmask', $filecaps[$cachedcap->name])) {
$filecaps[$cachedcap->name]['riskbitmask'] = 0; // no risk if not specified
}
if ($cachedcap->captype != $filecaps[$cachedcap->name]['captype']) {
$updatecap = new stdClass();
$updatecap->id = $cachedcap->id;
$updatecap->captype = $filecaps[$cachedcap->name]['captype'];
$DB->update_record('capabilities', $updatecap);
}
if ($cachedcap->riskbitmask != $filecaps[$cachedcap->name]['riskbitmask']) {
$updatecap = new stdClass();
$updatecap->id = $cachedcap->id;
$updatecap->riskbitmask = $filecaps[$cachedcap->name]['riskbitmask'];
$DB->update_record('capabilities', $updatecap);
}
if (!array_key_exists('contextlevel', $filecaps[$cachedcap->name])) {
$filecaps[$cachedcap->name]['contextlevel'] = 0; // no context level defined
}
if ($cachedcap->contextlevel != $filecaps[$cachedcap->name]['contextlevel']) {
$updatecap = new stdClass();
$updatecap->id = $cachedcap->id;
$updatecap->contextlevel = $filecaps[$cachedcap->name]['contextlevel'];
$DB->update_record('capabilities', $updatecap);
}
}
}
}
// Are there new capabilities in the file definition?
$newcaps = array();
foreach ($filecaps as $filecap => $def) {
if (!$storedcaps ||
($storedcaps && in_array($filecap, $storedcaps) === false)) {
if (!array_key_exists('riskbitmask', $def)) {
$def['riskbitmask'] = 0; // no risk if not specified
}
$newcaps[$filecap] = $def;
}
}
// Add new capabilities to the stored definition.
foreach ($newcaps as $capname => $capdef) {
$capability = new stdClass();
$capability->name = $capname;
$capability->captype = $capdef['captype'];
$capability->contextlevel = $capdef['contextlevel'];
$capability->component = $component;
$capability->riskbitmask = $capdef['riskbitmask'];
$DB->insert_record('capabilities', $capability, false);
if (isset($capdef['clonepermissionsfrom']) && in_array($capdef['clonepermissionsfrom'], $storedcaps)){
if ($rolecapabilities = $DB->get_records('role_capabilities', array('capability'=>$capdef['clonepermissionsfrom']))){
foreach ($rolecapabilities as $rolecapability){
//assign_capability will update rather than insert if capability exists
if (!assign_capability($capname, $rolecapability->permission,
$rolecapability->roleid, $rolecapability->contextid, true)){
echo $OUTPUT->notification('Could not clone capabilities for '.$capname);
}
}
}
// we ignore archetype key if we have cloned permissions
} else if (isset($capdef['archetypes']) && is_array($capdef['archetypes'])) {
assign_legacy_capabilities($capname, $capdef['archetypes']);
// 'legacy' is for backward compatibility with 1.9 access.php
} else if (isset($capdef['legacy']) && is_array($capdef['legacy'])) {
assign_legacy_capabilities($capname, $capdef['legacy']);
}
}
// Are there any capabilities that have been removed from the file
// definition that we need to delete from the stored capabilities and
// role assignments?
capabilities_cleanup($component, $filecaps);
// reset static caches
$ACCESSLIB_PRIVATE->capabilities = null;
return true;
}
/**
* Deletes cached capabilities that are no longer needed by the component.
* Also unassigns these capabilities from any roles that have them.
*
* @param string $component examples: 'moodle', 'mod_forum', 'block_quiz_results'
* @param array $newcapdef array of the new capability definitions that will be
* compared with the cached capabilities
* @return int number of deprecated capabilities that have been removed
*/
function capabilities_cleanup($component, $newcapdef = null) {
global $DB;
$removedcount = 0;
if ($cachedcaps = get_cached_capabilities($component)) {
foreach ($cachedcaps as $cachedcap) {
if (empty($newcapdef) ||
array_key_exists($cachedcap->name, $newcapdef) === false) {
// Remove from capabilities cache.
$DB->delete_records('capabilities', array('name'=>$cachedcap->name));
$removedcount++;
// Delete from roles.
if ($roles = get_roles_with_capability($cachedcap->name)) {
foreach($roles as $role) {
if (!unassign_capability($cachedcap->name, $role->id)) {
print_error('cannotunassigncap', 'error', '', (object)array('cap'=>$cachedcap->name, 'role'=>$role->name));
}
}
}
} // End if.
}
}
return $removedcount;
}
//////////////////
// UI FUNCTIONS //
//////////////////
/**
* @param integer $contextlevel $context->context level. One of the CONTEXT_... constants.
* @return string the name for this type of context.
*/
function get_contextlevel_name($contextlevel) {
static $strcontextlevels = null;
if (is_null($strcontextlevels)) {
$strcontextlevels = array(
CONTEXT_SYSTEM => get_string('coresystem'),
CONTEXT_USER => get_string('user'),
CONTEXT_COURSECAT => get_string('category'),
CONTEXT_COURSE => get_string('course'),
CONTEXT_MODULE => get_string('activitymodule'),
CONTEXT_BLOCK => get_string('block')
);
}
return $strcontextlevels[$contextlevel];
}
/**
* Prints human readable context identifier.
*
* @param object $context the context.
* @param boolean $withprefix whether to prefix the name of the context with the
* type of context, e.g. User, Course, Forum, etc.
* @param boolean $short whether to user the short name of the thing. Only applies
* to course contexts
* @return string the human readable context name.
*/
function print_context_name($context, $withprefix = true, $short = false) {
global $DB;
$name = '';
switch ($context->contextlevel) {
case CONTEXT_SYSTEM:
$name = get_string('coresystem');
break;
case CONTEXT_USER:
if ($user = $DB->get_record('user', array('id'=>$context->instanceid))) {
if ($withprefix){
$name = get_string('user').': ';
}
$name .= fullname($user);
}
break;
case CONTEXT_COURSECAT:
if ($category = $DB->get_record('course_categories', array('id'=>$context->instanceid))) {
if ($withprefix){
$name = get_string('category').': ';
}
$name .=format_string($category->name);
}
break;
case CONTEXT_COURSE:
if ($context->instanceid == SITEID) {
$name = get_string('frontpage', 'admin');
} else {
if ($course = $DB->get_record('course', array('id'=>$context->instanceid))) {
if ($withprefix){
$name = get_string('course').': ';
}
if ($short){
$name .= format_string($course->shortname);
} else {
$name .= format_string($course->fullname);
}
}
}
break;
case CONTEXT_MODULE:
if ($cm = $DB->get_record_sql('SELECT cm.*, md.name AS modname FROM {course_modules} cm ' .
'JOIN {modules} md ON md.id = cm.module WHERE cm.id = ?', array($context->instanceid))) {
if ($mod = $DB->get_record($cm->modname, array('id' => $cm->instance))) {
if ($withprefix){
$name = get_string('modulename', $cm->modname).': ';
}
$name .= $mod->name;
}
}
break;
case CONTEXT_BLOCK:
if ($blockinstance = $DB->get_record('block_instances', array('id'=>$context->instanceid))) {
global $CFG;
require_once("$CFG->dirroot/blocks/moodleblock.class.php");
require_once("$CFG->dirroot/blocks/$blockinstance->blockname/block_$blockinstance->blockname.php");
$blockname = "block_$blockinstance->blockname";
if ($blockobject = new $blockname()) {
if ($withprefix){
$name = get_string('block').': ';
}
$name .= $blockobject->title;
}
}
break;
default:
print_error('unknowncontext');
return false;
}
return $name;
}
/**
* Get a URL for a context, if there is a natural one. For example, for
* CONTEXT_COURSE, this is the course page. For CONTEXT_USER it is the
* user profile page.
*
* @param object $context the context.
* @return moodle_url
*/
function get_context_url($context) {
global $COURSE, $DB;
switch ($context->contextlevel) {
case CONTEXT_USER:
if ($COURSE->id == SITEID) {
$url = new moodle_url('/user/profile.php', array('id'=>$context->instanceid));
} else {
$url = new moodle_url('/user/view.php', array('id'=>$context->instanceid, 'courseid'=>$COURSE->id));
}
return $url;;
case CONTEXT_COURSECAT: // Coursecat -> coursecat or site
return new moodle_url('/course/category.php', array('id'=>$context->instanceid));
case CONTEXT_COURSE: // 1 to 1 to course cat
if ($context->instanceid != SITEID) {
return new moodle_url('/course/view.php', array('id'=>$context->instanceid));
}
break;
case CONTEXT_MODULE: // 1 to 1 to course
if ($modname = $DB->get_field_sql('SELECT md.name AS modname FROM {course_modules} cm ' .
'JOIN {modules} md ON md.id = cm.module WHERE cm.id = ?', array($context->instanceid))) {
return new moodle_url('/mod/' . $modname . '/view.php', array('id'=>$context->instanceid));
}
break;
case CONTEXT_BLOCK:
$parentcontexts = get_parent_contexts($context, false);
$parent = reset($parentcontexts);
$parent = get_context_instance_by_id($parent);
return get_context_url($parent);
}
return new moodle_url('/');
}
/**
* Returns an array of all the known types of risk
* The array keys can be used, for example as CSS class names, or in calls to
* print_risk_icon. The values are the corresponding RISK_ constants.
*
* @return array all the known types of risk.
*/
function get_all_risks() {
return array(
'riskmanagetrust' => RISK_MANAGETRUST,
'riskconfig' => RISK_CONFIG,
'riskxss' => RISK_XSS,
'riskpersonal' => RISK_PERSONAL,
'riskspam' => RISK_SPAM,
'riskdataloss' => RISK_DATALOSS,
);
}
/**
* Return a link to moodle docs for a given capability name
*
* @param object $capability a capability - a row from the mdl_capabilities table.
* @return string the human-readable capability name as a link to Moodle Docs.
*/
function get_capability_docs_link($capability) {
global $CFG;
$url = get_docs_url('Capabilities/' . $capability->name);
return '<a onclick="this.target=\'docspopup\'" href="' . $url . '">' . get_capability_string($capability->name) . '</a>';
}
/**
* Extracts the relevant capabilities given a contextid.
* All case based, example an instance of forum context.
* Will fetch all forum related capabilities, while course contexts
* Will fetch all capabilities
*
* capabilities
* `name` varchar(150) NOT NULL,
* `captype` varchar(50) NOT NULL,
* `contextlevel` int(10) NOT NULL,
* `component` varchar(100) NOT NULL,
*
* @param object context
* @return array
*/
function fetch_context_capabilities($context) {
global $DB, $CFG;
$sort = 'ORDER BY contextlevel,component,name'; // To group them sensibly for display
$params = array();
switch ($context->contextlevel) {
case CONTEXT_SYSTEM: // all
$SQL = "SELECT *
FROM {capabilities}";
break;
case CONTEXT_USER:
$extracaps = array('moodle/grade:viewall');
list($extra, $params) = $DB->get_in_or_equal($extracaps, SQL_PARAMS_NAMED, 'cap');
$SQL = "SELECT *
FROM {capabilities}
WHERE contextlevel = ".CONTEXT_USER."
OR name $extra";
break;
case CONTEXT_COURSECAT: // course category context and bellow
$SQL = "SELECT *
FROM {capabilities}
WHERE contextlevel IN (".CONTEXT_COURSECAT.",".CONTEXT_COURSE.",".CONTEXT_MODULE.",".CONTEXT_BLOCK.")";
break;
case CONTEXT_COURSE: // course context and bellow
$SQL = "SELECT *
FROM {capabilities}
WHERE contextlevel IN (".CONTEXT_COURSE.",".CONTEXT_MODULE.",".CONTEXT_BLOCK.")";
break;
case CONTEXT_MODULE: // mod caps
$cm = $DB->get_record('course_modules', array('id'=>$context->instanceid));
$module = $DB->get_record('modules', array('id'=>$cm->module));
$subcaps = array();
$subpluginsfile = "$CFG->dirroot/mod/$module->name/db/subplugins.php";
if (file_exists($subpluginsfile)) {
$subplugins = array(); // should be redefined in the file
include($subpluginsfile);
if (!empty($subplugins)) {
foreach (array_keys($subplugins) as $subplugintype) {
foreach (array_keys(get_plugin_list($subplugintype)) as $subpluginname) {
$subcaps = array_merge($subcaps, array_keys(load_capability_def($subplugintype.'_'.$subpluginname)));
}
}
}
}
$modfile = "$CFG->dirroot/mod/$module->name/lib.php";
if (file_exists($modfile)) {
include_once($modfile);
$modfunction = $module->name.'_get_extra_capabilities';
if (function_exists($modfunction)) {
$extracaps = $modfunction();
}
}
if (empty($extracaps)) {
$extracaps = array();
}
$extracaps = array_merge($subcaps, $extracaps);
// All modules allow viewhiddenactivities. This is so you can hide
// the module then override to allow specific roles to see it.
// The actual check is in course page so not module-specific
$extracaps[]="moodle/course:viewhiddenactivities";
list($extra, $params) = $DB->get_in_or_equal(
$extracaps, SQL_PARAMS_NAMED, 'cap0');
$extra = "OR name $extra";
$SQL = "SELECT *
FROM {capabilities}
WHERE (contextlevel = ".CONTEXT_MODULE."
AND component = :component)
$extra";
$params['component'] = "mod_$module->name";
break;
case CONTEXT_BLOCK: // block caps
$bi = $DB->get_record('block_instances', array('id' => $context->instanceid));
$extra = '';
$extracaps = block_method_result($bi->blockname, 'get_extra_capabilities');
if ($extracaps) {
list($extra, $params) = $DB->get_in_or_equal($extracaps, SQL_PARAMS_NAMED, 'cap');
$extra = "OR name $extra";
}
$SQL = "SELECT *
FROM {capabilities}
WHERE (contextlevel = ".CONTEXT_BLOCK."
AND component = :component)
$extra";
$params['component'] = 'block_' . $bi->blockname;
break;
default:
return false;
}
if (!$records = $DB->get_records_sql($SQL.' '.$sort, $params)) {
$records = array();
}
return $records;
}
/**
* This function pulls out all the resolved capabilities (overrides and
* defaults) of a role used in capability overrides in contexts at a given
* context.
*
* @param obj $context
* @param int $roleid
* @param string $cap capability, optional, defaults to ''
* @return array of capabilities
*/
function role_context_capabilities($roleid, $context, $cap = '') {
global $DB;
$contexts = get_parent_contexts($context);
$contexts[] = $context->id;
$contexts = '('.implode(',', $contexts).')';
$params = array($roleid);
if ($cap) {
$search = " AND rc.capability = ? ";
$params[] = $cap;
} else {
$search = '';
}
$sql = "SELECT rc.*
FROM {role_capabilities} rc, {context} c
WHERE rc.contextid in $contexts
AND rc.roleid = ?
AND rc.contextid = c.id $search
ORDER BY c.contextlevel DESC, rc.capability DESC";
$capabilities = array();
if ($records = $DB->get_records_sql($sql, $params)) {
// We are traversing via reverse order.
foreach ($records as $record) {
// If not set yet (i.e. inherit or not set at all), or currently we have a prohibit
if (!isset($capabilities[$record->capability]) || $record->permission<-500) {
$capabilities[$record->capability] = $record->permission;
}
}
}
return $capabilities;
}
/**
* Recursive function which, given a context, find all parent context ids,
* and return the array in reverse order, i.e. parent first, then grand
* parent, etc.
*
* @param object $context
* @param bool $capability optional, defaults to false
* @return array
*/
function get_parent_contexts($context, $includeself = false) {
if ($context->path == '') {
return array();
}
$parentcontexts = substr($context->path, 1); // kill leading slash
$parentcontexts = explode('/', $parentcontexts);
if (!$includeself) {
array_pop($parentcontexts); // and remove its own id
}
return array_reverse($parentcontexts);
}
/**
* Return the id of the parent of this context, or false if there is no parent (only happens if this
* is the site context.)
*
* @param object $context
* @return integer the id of the parent context.
*/
function get_parent_contextid($context) {
$parentcontexts = get_parent_contexts($context);
if (count($parentcontexts) == 0) {
return false;
}
return array_shift($parentcontexts);
}
/**
* Constructs array with contextids as first parameter and context paths,
* in both cases bottom top including self.
*
* @param object $context
* @return array
*/
function get_context_info_list($context) {
$contextids = explode('/', ltrim($context->path, '/'));
$contextpaths = array();
$contextids2 = $contextids;
while ($contextids2) {
$contextpaths[] = '/' . implode('/', $contextids2);
array_pop($contextids2);
}
return array($contextids, $contextpaths);
}
/**
* Find course context
* @param object $context - course or lower context
* @return object context of the enclosing course, throws exception when related course context can not be found
*/
function get_course_context($context) {
if (empty($context->contextlevel)) {
throw new coding_exception('Invalid context parameter.');
} if ($context->contextlevel == CONTEXT_COURSE) {
return $context;
} else if ($context->contextlevel == CONTEXT_MODULE) {
return get_context_instance_by_id(get_parent_contextid($context, MUST_EXIST));
} else if ($context->contextlevel == CONTEXT_BLOCK) {
$parentcontext = get_context_instance_by_id(get_parent_contextid($context, MUST_EXIST));
if ($parentcontext->contextlevel == CONTEXT_COURSE) {
return $parentcontext;
} else if ($parentcontext->contextlevel == CONTEXT_MODULE) {
return get_context_instance_by_id(get_parent_contextid($parentcontext, MUST_EXIST));
} else {
throw new coding_exception('Invalid level of block context parameter.');
}
}
throw new coding_exception('Invalid context level of parameter.');
}
/**
* Check if context is the front page context or a context inside it
*
* Returns true if this context is the front page context, or a context inside it,
* otherwise false.
*
* @param object $context a context object.
* @return bool
*/
function is_inside_frontpage($context) {
$frontpagecontext = get_context_instance(CONTEXT_COURSE, SITEID);
return strpos($context->path . '/', $frontpagecontext->path . '/') === 0;
}
/**
* Runs get_records select on context table and returns the result
* Does get_records_select on the context table, and returns the results ordered
* by contextlevel, and then the natural sort order within each level.
* for the purpose of $select, you need to know that the context table has been
* aliased to ctx, so for example, you can call get_sorted_contexts('ctx.depth = 3');
*
* @param string $select the contents of the WHERE clause. Remember to do ctx.fieldname.
* @param array $params any parameters required by $select.
* @return array the requested context records.
*/
function get_sorted_contexts($select, $params = array()) {
global $DB;
if ($select) {
$select = 'WHERE ' . $select;
}
return $DB->get_records_sql("
SELECT ctx.*
FROM {context} ctx
LEFT JOIN {user} u ON ctx.contextlevel = " . CONTEXT_USER . " AND u.id = ctx.instanceid
LEFT JOIN {course_categories} cat ON ctx.contextlevel = " . CONTEXT_COURSECAT . " AND cat.id = ctx.instanceid
LEFT JOIN {course} c ON ctx.contextlevel = " . CONTEXT_COURSE . " AND c.id = ctx.instanceid
LEFT JOIN {course_modules} cm ON ctx.contextlevel = " . CONTEXT_MODULE . " AND cm.id = ctx.instanceid
LEFT JOIN {block_instances} bi ON ctx.contextlevel = " . CONTEXT_BLOCK . " AND bi.id = ctx.instanceid
$select
ORDER BY ctx.contextlevel, bi.defaultregion, COALESCE(cat.sortorder, c.sortorder, cm.section, bi.defaultweight), u.lastname, u.firstname, cm.id
", $params);
}
/**
* Recursive function which, given a context, find all its children context ids.
*
* When called for a course context, it will return the modules and blocks
* displayed in the course page.
*
* For course category contexts it will return categories and courses. It will
* NOT recurse into courses, nor return blocks on the category pages. If you
* want to do that, call it on the returned courses.
*
* If called on a course context it _will_ populate the cache with the appropriate
* contexts ;-)
*
* @param object $context.
* @return array Array of child records
*/
function get_child_contexts($context) {
global $DB, $ACCESSLIB_PRIVATE;
// We *MUST* populate the context_cache as the callers
// will probably ask for the full record anyway soon after
// soon after calling us ;-)
$array = array();
$cache = $ACCESSLIB_PRIVATE->contexcache;
switch ($context->contextlevel) {
case CONTEXT_BLOCK:
// No children.
break;
case CONTEXT_MODULE:
// Find
// - blocks under this context path.
$sql = " SELECT ctx.*
FROM {context} ctx
WHERE ctx.path LIKE ?
AND ctx.contextlevel = ".CONTEXT_BLOCK;
$params = array("{$context->path}/%", $context->instanceid);
$records = $DB->get_recordset_sql($sql, $params);
foreach ($records as $rec) {
$cache->add($rec);
$array[$rec->id] = $rec;
}
break;
case CONTEXT_COURSE:
// Find
// - modules and blocks under this context path.
$sql = " SELECT ctx.*
FROM {context} ctx
WHERE ctx.path LIKE ?
AND ctx.contextlevel IN (".CONTEXT_MODULE.",".CONTEXT_BLOCK.")";
$params = array("{$context->path}/%", $context->instanceid);
$records = $DB->get_recordset_sql($sql, $params);
foreach ($records as $rec) {
$cache->add($rec);
$array[$rec->id] = $rec;
}
break;
case CONTEXT_COURSECAT:
// Find
// - categories
// - courses
$sql = " SELECT ctx.*
FROM {context} ctx
WHERE ctx.path LIKE ?
AND ctx.contextlevel IN (".CONTEXT_COURSECAT.",".CONTEXT_COURSE.")";
$params = array("{$context->path}/%");
$records = $DB->get_recordset_sql($sql, $params);
foreach ($records as $rec) {
$cache->add($rec);
$array[$rec->id] = $rec;
}
break;
case CONTEXT_USER:
// Find
// - blocks under this context path.
$sql = " SELECT ctx.*
FROM {context} ctx
WHERE ctx.path LIKE ?
AND ctx.contextlevel = ".CONTEXT_BLOCK;
$params = array("{$context->path}/%", $context->instanceid);
$records = $DB->get_recordset_sql($sql, $params);
foreach ($records as $rec) {
$cache->add($rec);
$array[$rec->id] = $rec;
}
break;
case CONTEXT_SYSTEM:
// Just get all the contexts except for CONTEXT_SYSTEM level
// and hope we don't OOM in the process - don't cache
$sql = "SELECT c.*
FROM {context} c
WHERE contextlevel != ".CONTEXT_SYSTEM;
$records = $DB->get_records_sql($sql);
foreach ($records as $rec) {
$array[$rec->id] = $rec;
}
break;
default:
print_error('unknowcontext', '', '', $context->contextlevel);
return false;
}
return $array;
}
/**
* Gets a string for sql calls, searching for stuff in this context or above
*
* @param object $context
* @return string
*/
function get_related_contexts_string($context) {
if ($parents = get_parent_contexts($context)) {
return (' IN ('.$context->id.','.implode(',', $parents).')');
} else {
return (' ='.$context->id);
}
}
/**
* Returns capability information (cached)
*
* @param string $capabilityname
* @return object or null if capability not found
*/
function get_capability_info($capabilityname) {
global $ACCESSLIB_PRIVATE, $DB; // one request per page only
// TODO: cache this in shared memory if available, use new $CFG->roledefrev for version check
if (empty($ACCESSLIB_PRIVATE->capabilities)) {
$ACCESSLIB_PRIVATE->capabilities = array();
$caps = $DB->get_records('capabilities', array(), 'id, name, captype, riskbitmask');
foreach ($caps as $cap) {
$capname = $cap->name;
unset($cap->id);
unset($cap->name);
$ACCESSLIB_PRIVATE->capabilities[$capname] = $cap;
}
}
return isset($ACCESSLIB_PRIVATE->capabilities[$capabilityname]) ? $ACCESSLIB_PRIVATE->capabilities[$capabilityname] : null;
}
/**
* Returns the human-readable, translated version of the capability.
* Basically a big switch statement.
*
* @param string $capabilityname e.g. mod/choice:readresponses
* @return string
*/
function get_capability_string($capabilityname) {
// Typical capability name is 'plugintype/pluginname:capabilityname'
list($type, $name, $capname) = preg_split('|[/:]|', $capabilityname);
if ($type === 'moodle') {
$component = 'core_role';
} else if ($type === 'quizreport') {
//ugly hack!!
$component = 'quiz_'.$name;
} else {
$component = $type.'_'.$name;
}
$stringname = $name.':'.$capname;
if ($component === 'core_role' or get_string_manager()->string_exists($stringname, $component)) {
return get_string($stringname, $component);
}
$dir = get_component_directory($component);
if (!file_exists($dir)) {
// plugin broken or does not exist, do not bother with printing of debug message
return $capabilityname.' ???';
}
// something is wrong in plugin, better print debug
return get_string($stringname, $component);
}
/**
* This gets the mod/block/course/core etc strings.
*
* @param string $component
* @param int $contextlevel
* @return string|bool String is success, false if failed
*/
function get_component_string($component, $contextlevel) {
if ($component === 'moodle' or $component === 'core') {
switch ($contextlevel) {
case CONTEXT_SYSTEM: return get_string('coresystem');
case CONTEXT_USER: return get_string('users');
case CONTEXT_COURSECAT: return get_string('categories');
case CONTEXT_COURSE: return get_string('course');
case CONTEXT_MODULE: return get_string('activities');
case CONTEXT_BLOCK: return get_string('block');
default: print_error('unknowncontext');
}
}
list($type, $name) = normalize_component($component);
$dir = get_plugin_directory($type, $name);
if (!file_exists($dir)) {
// plugin not installed, bad luck, there is no way to find the name
return $component.' ???';
}
switch ($type) {
// TODO this is really hacky
case 'quiz': return get_string($name.':componentname', $component);// insane hack!!!
case 'repository': return get_string('repository', 'repository').': '.get_string('pluginname', $component);
case 'gradeimport': return get_string('gradeimport', 'grades').': '.get_string('pluginname', $component);
case 'gradeexport': return get_string('gradeexport', 'grades').': '.get_string('pluginname', $component);
case 'gradereport': return get_string('gradereport', 'grades').': '.get_string('pluginname', $component);
case 'webservice': return get_string('webservice', 'webservice').': '.get_string('pluginname', $component);
case 'block': return get_string('block').': '.get_string('pluginname', basename($component));
case 'mod':
if (get_string_manager()->string_exists('pluginname', $component)) {
return get_string('activity').': '.get_string('pluginname', $component);
} else {
return get_string('activity').': '.get_string('modulename', $component);
}
default: return get_string('pluginname', $component);
}
}
/**
* Gets the list of roles assigned to this context and up (parents)
* from the list of roles that are visible on user profile page
* and participants page.
*
* @param object $context
* @return array
*/
function get_profile_roles($context) {
global $CFG, $DB;
if (empty($CFG->profileroles)) {
return array();
}
$allowed = explode(',', $CFG->profileroles);
list($rallowed, $params) = $DB->get_in_or_equal($allowed, SQL_PARAMS_NAMED);
$contextlist = get_related_contexts_string($context);
$sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder
FROM {role_assignments} ra, {role} r
WHERE r.id = ra.roleid
AND ra.contextid $contextlist
AND r.id $rallowed
ORDER BY r.sortorder ASC";
return $DB->get_records_sql($sql, $params);
}
/**
* Gets the list of roles assigned to this context and up (parents)
*
* @param object $context
* @return array
*/
function get_roles_used_in_context($context) {
global $DB;
$contextlist = get_related_contexts_string($context);
$sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder
FROM {role_assignments} ra, {role} r
WHERE r.id = ra.roleid
AND ra.contextid $contextlist
ORDER BY r.sortorder ASC";
return $DB->get_records_sql($sql);
}
/**
* This function is used to print roles column in user profile page.
* It is using the CFG->profileroles to limit the list to only interesting roles.
* (The permission tab has full details of user role assignments.)
*
* @param int $userid
* @param int $courseid
* @return string
*/
function get_user_roles_in_course($userid, $courseid) {
global $CFG, $DB,$USER;
if (empty($CFG->profileroles)) {
return '';
}
if ($courseid == SITEID) {
$context = get_context_instance(CONTEXT_SYSTEM);
} else {
$context = get_context_instance(CONTEXT_COURSE, $courseid);
}
if (empty($CFG->profileroles)) {
return array();
}
$allowed = explode(',', $CFG->profileroles);
list($rallowed, $params) = $DB->get_in_or_equal($allowed, SQL_PARAMS_NAMED);
$contextlist = get_related_contexts_string($context);
$sql = "SELECT DISTINCT r.id, r.name, r.shortname, r.sortorder
FROM {role_assignments} ra, {role} r
WHERE r.id = ra.roleid
AND ra.contextid $contextlist
AND r.id $rallowed
AND ra.userid = :userid
ORDER BY r.sortorder ASC";
$params['userid'] = $userid;
$rolestring = '';
if ($roles = $DB->get_records_sql($sql, $params)) {
foreach ($roles as $userrole) {
$rolenames[$userrole->id] = $userrole->name;
}
$rolenames = role_fix_names($rolenames, $context); // Substitute aliases
foreach ($rolenames as $roleid => $rolename) {
$rolenames[$roleid] = '<a href="'.$CFG->wwwroot.'/user/index.php?contextid='.$context->id.'&roleid='.$roleid.'">'.$rolename.'</a>';
}
$rolestring = implode(',', $rolenames);
}
return $rolestring;
}
/**
* Checks if a user can assign users to a particular role in this context
*
* @param object $context
* @param int $targetroleid - the id of the role you want to assign users to
* @return boolean
*/
function user_can_assign($context, $targetroleid) {
global $DB;
// first check if user has override capability
// if not return false;
if (!has_capability('moodle/role:assign', $context)) {
return false;
}
// pull out all active roles of this user from this context(or above)
if ($userroles = get_user_roles($context)) {
foreach ($userroles as $userrole) {
// if any in the role_allow_override table, then it's ok
if ($DB->get_record('role_allow_assign', array('roleid'=>$userrole->roleid, 'allowassign'=>$targetroleid))) {
return true;
}
}
}
return false;
}
/**
* Returns all site roles in correct sort order.
*
* @return array
*/
function get_all_roles() {
global $DB;
return $DB->get_records('role', null, 'sortorder ASC');
}
/**
* Returns roles of a specified archetype
* @param string $archetype
* @return array of full role records
*/
function get_archetype_roles($archetype) {
global $DB;
return $DB->get_records('role', array('archetype'=>$archetype), 'sortorder ASC');
}
/**
* Gets all the user roles assigned in this context, or higher contexts
* this is mainly used when checking if a user can assign a role, or overriding a role
* i.e. we need to know what this user holds, in order to verify against allow_assign and
* allow_override tables
*
* @param object $context
* @param int $userid
* @param bool $checkparentcontexts defaults to true
* @param string $order defaults to 'c.contextlevel DESC, r.sortorder ASC'
* @return array
*/
function get_user_roles($context, $userid = 0, $checkparentcontexts = true, $order = 'c.contextlevel DESC, r.sortorder ASC') {
global $USER, $DB;
if (empty($userid)) {
if (empty($USER->id)) {
return array();
}
$userid = $USER->id;
}
if ($checkparentcontexts) {
$contextids = get_parent_contexts($context);
} else {
$contextids = array();
}
$contextids[] = $context->id;
list($contextids, $params) = $DB->get_in_or_equal($contextids, SQL_PARAMS_QM);
array_unshift($params, $userid);
$sql = "SELECT ra.*, r.name, r.shortname
FROM {role_assignments} ra, {role} r, {context} c
WHERE ra.userid = ?
AND ra.roleid = r.id
AND ra.contextid = c.id
AND ra.contextid $contextids
ORDER BY $order";
return $DB->get_records_sql($sql ,$params);
}
/**
* Creates a record in the role_allow_override table
*
* @param int $sroleid source roleid
* @param int $troleid target roleid
* @return void
*/
function allow_override($sroleid, $troleid) {
global $DB;
$record = new stdClass();
$record->roleid = $sroleid;
$record->allowoverride = $troleid;
$DB->insert_record('role_allow_override', $record);
}
/**
* Creates a record in the role_allow_assign table
*
* @param int $sroleid source roleid
* @param int $troleid target roleid
* @return void
*/
function allow_assign($fromroleid, $targetroleid) {
global $DB;
$record = new stdClass();
$record->roleid = $fromroleid;
$record->allowassign = $targetroleid;
$DB->insert_record('role_allow_assign', $record);
}
/**
* Creates a record in the role_allow_switch table
*
* @param int $sroleid source roleid
* @param int $troleid target roleid
* @return void
*/
function allow_switch($fromroleid, $targetroleid) {
global $DB;
$record = new stdClass();
$record->roleid = $fromroleid;
$record->allowswitch = $targetroleid;
$DB->insert_record('role_allow_switch', $record);
}
/**
* Gets a list of roles that this user can assign in this context
*
* @param object $context the context.
* @param int $rolenamedisplay the type of role name to display. One of the
* ROLENAME_X constants. Default ROLENAME_ALIAS.
* @param bool $withusercounts if true, count the number of users with each role.
* @param integer|object $user A user id or object. By default (null) checks the permissions of the current user.
* @return array if $withusercounts is false, then an array $roleid => $rolename.
* if $withusercounts is true, returns a list of three arrays,
* $rolenames, $rolecounts, and $nameswithcounts.
*/
function get_assignable_roles($context, $rolenamedisplay = ROLENAME_ALIAS, $withusercounts = false, $user = null) {
global $USER, $DB;
// make sure there is a real user specified
if ($user === null) {
$userid = isset($USER->id) ? $USER->id : 0;
} else {
$userid = is_object($user) ? $user->id : $user;
}
if (!has_capability('moodle/role:assign', $context, $userid)) {
if ($withusercounts) {
return array(array(), array(), array());
} else {
return array();
}
}
$parents = get_parent_contexts($context, true);
$contexts = implode(',' , $parents);
$params = array();
$extrafields = '';
if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT or $rolenamedisplay == ROLENAME_SHORT) {
$extrafields .= ', r.shortname';
}
if ($withusercounts) {
$extrafields = ', (SELECT count(u.id)
FROM {role_assignments} cra JOIN {user} u ON cra.userid = u.id
WHERE cra.roleid = r.id AND cra.contextid = :conid AND u.deleted = 0
) AS usercount';
$params['conid'] = $context->id;
}
if (is_siteadmin($userid)) {
// show all roles allowed in this context to admins
$assignrestriction = "";
} else {
$assignrestriction = "JOIN (SELECT DISTINCT raa.allowassign AS id
FROM {role_allow_assign} raa
JOIN {role_assignments} ra ON ra.roleid = raa.roleid
WHERE ra.userid = :userid AND ra.contextid IN ($contexts)
) ar ON ar.id = r.id";
$params['userid'] = $userid;
}
$params['contextlevel'] = $context->contextlevel;
$sql = "SELECT r.id, r.name $extrafields
FROM {role} r
$assignrestriction
JOIN {role_context_levels} rcl ON r.id = rcl.roleid
WHERE rcl.contextlevel = :contextlevel
ORDER BY r.sortorder ASC";
$roles = $DB->get_records_sql($sql, $params);
$rolenames = array();
foreach ($roles as $role) {
if ($rolenamedisplay == ROLENAME_SHORT) {
$rolenames[$role->id] = $role->shortname;
continue;
}
$rolenames[$role->id] = $role->name;
if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT) {
$rolenames[$role->id] .= ' (' . $role->shortname . ')';
}
}
if ($rolenamedisplay != ROLENAME_ORIGINALANDSHORT and $rolenamedisplay != ROLENAME_SHORT) {
$rolenames = role_fix_names($rolenames, $context, $rolenamedisplay);
}
if (!$withusercounts) {
return $rolenames;
}
$rolecounts = array();
$nameswithcounts = array();
foreach ($roles as $role) {
$nameswithcounts[$role->id] = $rolenames[$role->id] . ' (' . $roles[$role->id]->usercount . ')';
$rolecounts[$role->id] = $roles[$role->id]->usercount;
}
return array($rolenames, $rolecounts, $nameswithcounts);
}
/**
* Gets a list of roles that this user can switch to in a context
*
* Gets a list of roles that this user can switch to in a context, for the switchrole menu.
* This function just process the contents of the role_allow_switch table. You also need to
* test the moodle/role:switchroles to see if the user is allowed to switch in the first place.
*
* @param object $context a context.
* @return array an array $roleid => $rolename.
*/
function get_switchable_roles($context) {
global $USER, $DB;
$systemcontext = get_context_instance(CONTEXT_SYSTEM);
$params = array();
$extrajoins = '';
$extrawhere = '';
if (!is_siteadmin()) {
// Admins are allowed to switch to any role with.
// Others are subject to the additional constraint that the switch-to role must be allowed by
// 'role_allow_switch' for some role they have assigned in this context or any parent.
$parents = get_parent_contexts($context);
$parents[] = $context->id;
$contexts = implode(',' , $parents);
$extrajoins = "JOIN {role_allow_switch} ras ON ras.allowswitch = rc.roleid
JOIN {role_assignments} ra ON ra.roleid = ras.roleid";
$extrawhere = "WHERE ra.userid = :userid AND ra.contextid IN ($contexts)";
$params['userid'] = $USER->id;
}
$query = "
SELECT r.id, r.name
FROM (SELECT DISTINCT rc.roleid
FROM {role_capabilities} rc
$extrajoins
$extrawhere) idlist
JOIN {role} r ON r.id = idlist.roleid
ORDER BY r.sortorder";
$rolenames = $DB->get_records_sql_menu($query, $params);
return role_fix_names($rolenames, $context, ROLENAME_ALIAS);
}
/**
* Gets a list of roles that this user can override in this context.
*
* @param object $context the context.
* @param int $rolenamedisplay the type of role name to display. One of the
* ROLENAME_X constants. Default ROLENAME_ALIAS.
* @param bool $withcounts if true, count the number of overrides that are set for each role.
* @return array if $withcounts is false, then an array $roleid => $rolename.
* if $withusercounts is true, returns a list of three arrays,
* $rolenames, $rolecounts, and $nameswithcounts.
*/
function get_overridable_roles($context, $rolenamedisplay = ROLENAME_ALIAS, $withcounts = false) {
global $USER, $DB;
if (!has_any_capability(array('moodle/role:safeoverride', 'moodle/role:override'), $context)) {
if ($withcounts) {
return array(array(), array(), array());
} else {
return array();
}
}
$parents = get_parent_contexts($context);
$parents[] = $context->id;
$contexts = implode(',' , $parents);
$params = array();
$extrafields = '';
if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT) {
$extrafields .= ', ro.shortname';
}
$params['userid'] = $USER->id;
if ($withcounts) {
$extrafields = ', (SELECT count(rc.id) FROM {role_capabilities} rc
WHERE rc.roleid = ro.id AND rc.contextid = :conid) AS overridecount';
$params['conid'] = $context->id;
}
if (is_siteadmin()) {
// show all roles to admins
$roles = $DB->get_records_sql("
SELECT ro.id, ro.name$extrafields
FROM {role} ro
ORDER BY ro.sortorder ASC", $params);
} else {
$roles = $DB->get_records_sql("
SELECT ro.id, ro.name$extrafields
FROM {role} ro
JOIN (SELECT DISTINCT r.id
FROM {role} r
JOIN {role_allow_override} rao ON r.id = rao.allowoverride
JOIN {role_assignments} ra ON rao.roleid = ra.roleid
WHERE ra.userid = :userid AND ra.contextid IN ($contexts)
) inline_view ON ro.id = inline_view.id
ORDER BY ro.sortorder ASC", $params);
}
$rolenames = array();
foreach ($roles as $role) {
$rolenames[$role->id] = $role->name;
if ($rolenamedisplay == ROLENAME_ORIGINALANDSHORT) {
$rolenames[$role->id] .= ' (' . $role->shortname . ')';
}
}
if ($rolenamedisplay != ROLENAME_ORIGINALANDSHORT) {
$rolenames = role_fix_names($rolenames, $context, $rolenamedisplay);
}
if (!$withcounts) {
return $rolenames;
}
$rolecounts = array();
$nameswithcounts = array();
foreach ($roles as $role) {
$nameswithcounts[$role->id] = $rolenames[$role->id] . ' (' . $roles[$role->id]->overridecount . ')';
$rolecounts[$role->id] = $roles[$role->id]->overridecount;
}
return array($rolenames, $rolecounts, $nameswithcounts);
}
/**
* Create a role menu suitable for default role selection in enrol plugins.
* @param object $context
* @param int $addroleid current or default role - always added to list
* @return array roleid=>localised role name
*/
function get_default_enrol_roles($context, $addroleid = null) {
global $DB;
$params = array('contextlevel'=>CONTEXT_COURSE);
if ($addroleid) {
$addrole = "OR r.id = :addroleid";
$params['addroleid'] = $addroleid;
} else {
$addrole = "";
}
$sql = "SELECT r.id, r.name
FROM {role} r
LEFT JOIN {role_context_levels} rcl ON (rcl.roleid = r.id AND rcl.contextlevel = :contextlevel)
WHERE rcl.id IS NOT NULL $addrole
ORDER BY sortorder DESC";
$roles = $DB->get_records_sql_menu($sql, $params);
$roles = role_fix_names($roles, $context, ROLENAME_BOTH);
return $roles;
}
/**
* @param integer $roleid the id of a role.
* @return array list of the context levels at which this role may be assigned.
*/
function get_role_contextlevels($roleid) {
global $DB;
return $DB->get_records_menu('role_context_levels', array('roleid' => $roleid),
'contextlevel', 'id,contextlevel');
}
/**
* @param integer $contextlevel a contextlevel.
* @return array list of role ids that are assignable at this context level.
*/
function get_roles_for_contextlevels($contextlevel) {
global $DB;
return $DB->get_records_menu('role_context_levels', array('contextlevel' => $contextlevel),
'', 'id,roleid');
}
/**
* @param string $rolearchetype one of the role archetypes - that is, one of the keys
* from the array returned by get_role_archetypes();
* @return array list of the context levels at which this type of role may be assigned by default.
*/
function get_default_contextlevels($rolearchetype) {
static $defaults = array(
'manager' => array(CONTEXT_SYSTEM, CONTEXT_COURSECAT, CONTEXT_COURSE),
'coursecreator' => array(CONTEXT_SYSTEM, CONTEXT_COURSECAT),
'editingteacher' => array(CONTEXT_COURSE, CONTEXT_MODULE),
'teacher' => array(CONTEXT_COURSE, CONTEXT_MODULE),
'student' => array(CONTEXT_COURSE, CONTEXT_MODULE),
'guest' => array(),
'user' => array(),
'frontpage' => array());
if (isset($defaults[$rolearchetype])) {
return $defaults[$rolearchetype];
} else {
return array();
}
}
/**
* Set the context levels at which a particular role can be assigned.
* Throws exceptions in case of error.
*
* @param integer $roleid the id of a role.
* @param array $contextlevels the context levels at which this role should be assignable,
* duplicate levels are removed.
* @return void
*/
function set_role_contextlevels($roleid, array $contextlevels) {
global $DB;
$DB->delete_records('role_context_levels', array('roleid' => $roleid));
$rcl = new stdClass();
$rcl->roleid = $roleid;
$contextlevels = array_unique($contextlevels);
foreach ($contextlevels as $level) {
$rcl->contextlevel = $level;
$DB->insert_record('role_context_levels', $rcl, false, true);
}
}
/**
* Who has this capability in this context?
*
* This can be a very expensive call - use sparingly and keep
* the results if you are going to need them again soon.
*
* Note if $fields is empty this function attempts to get u.*
* which can get rather large - and has a serious perf impact
* on some DBs.
*
* @param object $context
* @param string|array $capability - capability name(s)
* @param string $fields - fields to be pulled. The user table is aliased to 'u'. u.id MUST be included.
* @param string $sort - the sort order. Default is lastaccess time.
* @param mixed $limitfrom - number of records to skip (offset)
* @param mixed $limitnum - number of records to fetch
* @param string|array $groups - single group or array of groups - only return
* users who are in one of these group(s).
* @param string|array $exceptions - list of users to exclude, comma separated or array
* @param bool $doanything_ignored not used any more, admin accounts are never returned
* @param bool $view_ignored - use get_enrolled_sql() instead
* @param bool $useviewallgroups if $groups is set the return users who
* have capability both $capability and moodle/site:accessallgroups
* in this context, as well as users who have $capability and who are
* in $groups.
* @return mixed
*/
function get_users_by_capability($context, $capability, $fields = '', $sort = '', $limitfrom = '', $limitnum = '',
$groups = '', $exceptions = '', $doanything_ignored = null, $view_ignored = null, $useviewallgroups = false) {
global $CFG, $DB;
if (empty($context->id)) {
throw new coding_exception('Invalid context specified');
}
$defaultuserroleid = isset($CFG->defaultuserroleid) ? $CFG->defaultuserroleid : 0;
$defaultfrontpageroleid = isset($CFG->defaultfrontpageroleid) ? $CFG->defaultfrontpageroleid : 0;
$ctxids = trim($context->path, '/');
$ctxids = str_replace('/', ',', $ctxids);
// Context is the frontpage
$iscoursepage = false; // coursepage other than fp
$isfrontpage = false;
if ($context->contextlevel == CONTEXT_COURSE) {
if ($context->instanceid == SITEID) {
$isfrontpage = true;
} else {
$iscoursepage = true;
}
}
$isfrontpage = ($isfrontpage || is_inside_frontpage($context));
$caps = (array)$capability;
// construct list of context paths bottom-->top
list($contextids, $paths) = get_context_info_list($context);
// we need to find out all roles that have these capabilities either in definition or in overrides
$defs = array();
list($incontexts, $params) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED, 'con');
list($incaps, $params2) = $DB->get_in_or_equal($caps, SQL_PARAMS_NAMED, 'cap');
$params = array_merge($params, $params2);
$sql = "SELECT rc.id, rc.roleid, rc.permission, rc.capability, ctx.path
FROM {role_capabilities} rc
JOIN {context} ctx on rc.contextid = ctx.id
WHERE rc.contextid $incontexts AND rc.capability $incaps";
$rcs = $DB->get_records_sql($sql, $params);
foreach ($rcs as $rc) {
$defs[$rc->capability][$rc->path][$rc->roleid] = $rc->permission;
}
// go through the permissions bottom-->top direction to evaluate the current permission,
// first one wins (prohibit is an exception that always wins)
$access = array();
foreach ($caps as $cap) {
foreach ($paths as $path) {
if (empty($defs[$cap][$path])) {
continue;
}
foreach($defs[$cap][$path] as $roleid => $perm) {
if ($perm == CAP_PROHIBIT) {
$access[$cap][$roleid] = CAP_PROHIBIT;
continue;
}
if (!isset($access[$cap][$roleid])) {
$access[$cap][$roleid] = (int)$perm;
}
}
}
}
// make lists of roles that are needed and prohibited in this context
$needed = array(); // one of these is enough
$prohibited = array(); // must not have any of these
foreach ($caps as $cap) {
if (empty($access[$cap])) {
continue;
}
foreach ($access[$cap] as $roleid => $perm) {
if ($perm == CAP_PROHIBIT) {
unset($needed[$cap][$roleid]);
$prohibited[$cap][$roleid] = true;
} else if ($perm == CAP_ALLOW and empty($prohibited[$cap][$roleid])) {
$needed[$cap][$roleid] = true;
}
}
if (empty($needed[$cap]) or !empty($prohibited[$cap][$defaultuserroleid])) {
// easy, nobody has the permission
unset($needed[$cap]);
unset($prohibited[$cap]);
} else if ($isfrontpage and !empty($prohibited[$cap][$defaultfrontpageroleid])) {
// everybody is disqualified on the frontapge
unset($needed[$cap]);
unset($prohibited[$cap]);
}
if (empty($prohibited[$cap])) {
unset($prohibited[$cap]);
}
}
if (empty($needed)) {
// there can not be anybody if no roles match this request
return array();
}
if (empty($prohibited)) {
// we can compact the needed roles
$n = array();
foreach ($needed as $cap) {
foreach ($cap as $roleid=>$unused) {
$n[$roleid] = true;
}
}
$needed = array('any'=>$n);
unset($n);
}
/// ***** Set up default fields ******
if (empty($fields)) {
if ($iscoursepage) {
$fields = 'u.*, ul.timeaccess AS lastaccess';
} else {
$fields = 'u.*';
}
} else {
if (debugging('', DEBUG_DEVELOPER) && strpos($fields, 'u.*') === false && strpos($fields, 'u.id') === false) {
debugging('u.id must be included in the list of fields passed to get_users_by_capability().', DEBUG_DEVELOPER);
}
}
/// Set up default sort
if (empty($sort)) { // default to course lastaccess or just lastaccess
if ($iscoursepage) {
$sort = 'ul.timeaccess';
} else {
$sort = 'u.lastaccess';
}
}
$sortby = "ORDER BY $sort";
// Prepare query clauses
$wherecond = array();
$params = array();
$joins = array();
// User lastaccess JOIN
if ((strpos($sort, 'ul.timeaccess') === false) and (strpos($fields, 'ul.timeaccess') === false)) {
// user_lastaccess is not required MDL-13810
} else {
if ($iscoursepage) {
$joins[] = "LEFT OUTER JOIN {user_lastaccess} ul ON (ul.userid = u.id AND ul.courseid = {$context->instanceid})";
} else {
throw new coding_exception('Invalid sort in get_users_by_capability(), ul.timeaccess allowed only for course contexts.');
}
}
/// We never return deleted users or guest account.
$wherecond[] = "u.deleted = 0 AND u.id <> :guestid";
$params['guestid'] = $CFG->siteguest;
/// Groups
if ($groups) {
$groups = (array)$groups;
list($grouptest, $grpparams) = $DB->get_in_or_equal($groups, SQL_PARAMS_NAMED, 'grp');
$grouptest = "u.id IN (SELECT userid FROM {groups_members} gm WHERE gm.groupid $grouptest)";
$params = array_merge($params, $grpparams);
if ($useviewallgroups) {
$viewallgroupsusers = get_users_by_capability($context, 'moodle/site:accessallgroups', 'u.id, u.id', '', '', '', '', $exceptions);
if (!empty($viewallgroupsusers)) {
$wherecond[] = "($grouptest OR u.id IN (" . implode(',', array_keys($viewallgroupsusers)) . '))';
} else {
$wherecond[] = "($grouptest)";
}
} else {
$wherecond[] = "($grouptest)";
}
}
/// User exceptions
if (!empty($exceptions)) {
$exceptions = (array)$exceptions;
list($exsql, $exparams) = $DB->get_in_or_equal($exceptions, SQL_PARAMS_NAMED, 'exc', false);
$params = array_merge($params, $exparams);
$wherecond[] = "u.id $exsql";
}
// now add the needed and prohibited roles conditions as joins
if (!empty($needed['any'])) {
// simple case - there are no prohibits involved
if (!empty($needed['any'][$defaultuserroleid]) or ($isfrontpage and !empty($needed['any'][$defaultfrontpageroleid]))) {
// everybody
} else {
$joins[] = "JOIN (SELECT DISTINCT userid
FROM {role_assignments}
WHERE contextid IN ($ctxids)
AND roleid IN (".implode(',', array_keys($needed['any'])) .")
) ra ON ra.userid = u.id";
}
} else {
$unions = array();
$everybody = false;
foreach ($needed as $cap=>$unused) {
if (empty($prohibited[$cap])) {
if (!empty($needed[$cap][$defaultuserroleid]) or ($isfrontpage and !empty($needed[$cap][$defaultfrontpageroleid]))) {
$everybody = true;
break;
} else {
$unions[] = "SELECT userid
FROM {role_assignments}
WHERE contextid IN ($ctxids)
AND roleid IN (".implode(',', array_keys($needed[$cap])) .")";
}
} else {
if (!empty($prohibited[$cap][$defaultuserroleid]) or ($isfrontpage and !empty($prohibited[$cap][$defaultfrontpageroleid]))) {
// nobody can have this cap because it is prevented in default roles
continue;
} else if (!empty($needed[$cap][$defaultuserroleid]) or ($isfrontpage and !empty($needed[$cap][$defaultfrontpageroleid]))) {
// everybody except the prohibitted - hiding does not matter
$unions[] = "SELECT id AS userid
FROM {user}
WHERE id NOT IN (SELECT userid
FROM {role_assignments}
WHERE contextid IN ($ctxids)
AND roleid IN (".implode(',', array_keys($prohibited[$cap])) ."))";
} else {
$unions[] = "SELECT userid
FROM {role_assignments}
WHERE contextid IN ($ctxids)
AND roleid IN (".implode(',', array_keys($needed[$cap])) .")
AND roleid NOT IN (".implode(',', array_keys($prohibited[$cap])) .")";
}
}
}
if (!$everybody) {
if ($unions) {
$joins[] = "JOIN (SELECT DISTINCT userid FROM ( ".implode(' UNION ', $unions)." ) us) ra ON ra.userid = u.id";
} else {
// only prohibits found - nobody can be matched
$wherecond[] = "1 = 2";
}
}
}
// Collect WHERE conditions and needed joins
$where = implode(' AND ', $wherecond);
if ($where !== '') {
$where = 'WHERE ' . $where;
}
$joins = implode("\n", $joins);
/// Ok, let's get the users!
$sql = "SELECT $fields
FROM {user} u
$joins
$where
ORDER BY $sort";
return $DB->get_records_sql($sql, $params, $limitfrom, $limitnum);
}
/**
* Re-sort a users array based on a sorting policy
*
* Will re-sort a $users results array (from get_users_by_capability(), usually)
* based on a sorting policy. This is to support the odd practice of
* sorting teachers by 'authority', where authority was "lowest id of the role
* assignment".
*
* Will execute 1 database query. Only suitable for small numbers of users, as it
* uses an u.id IN() clause.
*
* Notes about the sorting criteria.
*
* As a default, we cannot rely on role.sortorder because then
* admins/coursecreators will always win. That is why the sane
* rule "is locality matters most", with sortorder as 2nd
* consideration.
*
* If you want role.sortorder, use the 'sortorder' policy, and
* name explicitly what roles you want to cover. It's probably
* a good idea to see what roles have the capabilities you want
* (array_diff() them against roiles that have 'can-do-anything'
* to weed out admin-ish roles. Or fetch a list of roles from
* variables like $CFG->coursecontact .
*
* @param array $users Users array, keyed on userid
* @param object $context
* @param array $roles ids of the roles to include, optional
* @param string $policy defaults to locality, more about
* @return array sorted copy of the array
*/
function sort_by_roleassignment_authority($users, $context, $roles = array(), $sortpolicy = 'locality') {
global $DB;
$userswhere = ' ra.userid IN (' . implode(',',array_keys($users)) . ')';
$contextwhere = 'AND ra.contextid IN ('.str_replace('/', ',',substr($context->path, 1)).')';
if (empty($roles)) {
$roleswhere = '';
} else {
$roleswhere = ' AND ra.roleid IN ('.implode(',',$roles).')';
}
$sql = "SELECT ra.userid
FROM {role_assignments} ra
JOIN {role} r
ON ra.roleid=r.id
JOIN {context} ctx
ON ra.contextid=ctx.id
WHERE $userswhere
$contextwhere
$roleswhere";
// Default 'locality' policy -- read PHPDoc notes
// about sort policies...
$orderby = 'ORDER BY '
.'ctx.depth DESC, ' /* locality wins */
.'r.sortorder ASC, ' /* rolesorting 2nd criteria */
.'ra.id'; /* role assignment order tie-breaker */
if ($sortpolicy === 'sortorder') {
$orderby = 'ORDER BY '
.'r.sortorder ASC, ' /* rolesorting 2nd criteria */
.'ra.id'; /* role assignment order tie-breaker */
}
$sortedids = $DB->get_fieldset_sql($sql . $orderby);
$sortedusers = array();
$seen = array();
foreach ($sortedids as $id) {
// Avoid duplicates
if (isset($seen[$id])) {
continue;
}
$seen[$id] = true;
// assign
$sortedusers[$id] = $users[$id];
}
return $sortedusers;
}
/**
* Gets all the users assigned this role in this context or higher
*
* @param int $roleid (can also be an array of ints!)
* @param stdClass $context
* @param bool $parent if true, get list of users assigned in higher context too
* @param string $fields fields from user (u.) , role assignment (ra) or role (r.)
* @param string $sort sort from user (u.) , role assignment (ra) or role (r.)
* @param bool $gethidden_ignored use enrolments instead
* @param string $group defaults to ''
* @param mixed $limitfrom defaults to ''
* @param mixed $limitnum defaults to ''
* @param string $extrawheretest defaults to ''
* @param string|array $whereparams defaults to ''
* @return array
*/
function get_role_users($roleid, $context, $parent = false, $fields = '',
$sort = 'u.lastname, u.firstname', $gethidden_ignored = null, $group = '',
$limitfrom = '', $limitnum = '', $extrawheretest = '', $whereparams = array()) {
global $DB;
if (empty($fields)) {
$fields = 'u.id, u.confirmed, u.username, u.firstname, u.lastname, '.
'u.maildisplay, u.mailformat, u.maildigest, u.email, u.city, '.
'u.country, u.picture, u.idnumber, u.department, u.institution, '.
'u.lang, u.timezone, u.lastaccess, u.mnethostid, r.name AS rolename, r.sortorder';
}
$parentcontexts = '';
if ($parent) {
$parentcontexts = substr($context->path, 1); // kill leading slash
$parentcontexts = str_replace('/', ',', $parentcontexts);
if ($parentcontexts !== '') {
$parentcontexts = ' OR ra.contextid IN ('.$parentcontexts.' )';
}
}
if ($roleid) {
list($rids, $params) = $DB->get_in_or_equal($roleid, SQL_PARAMS_QM);
$roleselect = "AND ra.roleid $rids";
} else {
$params = array();
$roleselect = '';
}
if ($group) {
$groupjoin = "JOIN {groups_members} gm ON gm.userid = u.id";
$groupselect = " AND gm.groupid = ? ";
$params[] = $group;
} else {
$groupjoin = '';
$groupselect = '';
}
array_unshift($params, $context->id);
if ($extrawheretest) {
$extrawheretest = ' AND ' . $extrawheretest;
$params = array_merge($params, $whereparams);
}
$sql = "SELECT DISTINCT $fields, ra.roleid
FROM {role_assignments} ra
JOIN {user} u ON u.id = ra.userid
JOIN {role} r ON ra.roleid = r.id
$groupjoin
WHERE (ra.contextid = ? $parentcontexts)
$roleselect
$groupselect
$extrawheretest
ORDER BY $sort"; // join now so that we can just use fullname() later
return $DB->get_records_sql($sql, $params, $limitfrom, $limitnum);
}
/**
* Counts all the users assigned this role in this context or higher
*
* @param mixed $roleid either int or an array of ints
* @param object $context
* @param bool $parent if true, get list of users assigned in higher context too
* @return int Returns the result count
*/
function count_role_users($roleid, $context, $parent = false) {
global $DB;
if ($parent) {
if ($contexts = get_parent_contexts($context)) {
$parentcontexts = ' OR r.contextid IN ('.implode(',', $contexts).')';
} else {
$parentcontexts = '';
}
} else {
$parentcontexts = '';
}
if ($roleid) {
list($rids, $params) = $DB->get_in_or_equal($roleid, SQL_PARAMS_QM);
$roleselect = "AND r.roleid $rids";
} else {
$params = array();
$roleselect = '';
}
array_unshift($params, $context->id);
$sql = "SELECT count(u.id)
FROM {role_assignments} r
JOIN {user} u ON u.id = r.userid
WHERE (r.contextid = ? $parentcontexts)
$roleselect
AND u.deleted = 0";
return $DB->count_records_sql($sql, $params);
}
/**
* This function gets the list of courses that this user has a particular capability in.
* It is still not very efficient.
*
* @param string $capability Capability in question
* @param int $userid User ID or null for current user
* @param bool $doanything True if 'doanything' is permitted (default)
* @param string $fieldsexceptid Leave blank if you only need 'id' in the course records;
* otherwise use a comma-separated list of the fields you require, not including id
* @param string $orderby If set, use a comma-separated list of fields from course
* table with sql modifiers (DESC) if needed
* @return array Array of courses, may have zero entries. Or false if query failed.
*/
function get_user_capability_course($capability, $userid = null, $doanything = true, $fieldsexceptid = '', $orderby = '') {
global $DB;
// Convert fields list and ordering
$fieldlist = '';
if ($fieldsexceptid) {
$fields = explode(',', $fieldsexceptid);
foreach($fields as $field) {
$fieldlist .= ',c.'.$field;
}
}
if ($orderby) {
$fields = explode(',', $orderby);
$orderby = '';
foreach($fields as $field) {
if ($orderby) {
$orderby .= ',';
}
$orderby .= 'c.'.$field;
}
$orderby = 'ORDER BY '.$orderby;
}
// Obtain a list of everything relevant about all courses including context.
// Note the result can be used directly as a context (we are going to), the course
// fields are just appended.
$courses = array();
$rs = $DB->get_recordset_sql("SELECT x.*, c.id AS courseid $fieldlist
FROM {course} c
INNER JOIN {context} x
ON (c.id=x.instanceid AND x.contextlevel=".CONTEXT_COURSE.")
$orderby");
// Check capability for each course in turn
foreach ($rs as $coursecontext) {
if (has_capability($capability, $coursecontext, $userid, $doanything)) {
// We've got the capability. Make the record look like a course record
// and store it
$coursecontext->id = $coursecontext->courseid;
unset($coursecontext->courseid);
unset($coursecontext->contextlevel);
unset($coursecontext->instanceid);
$courses[] = $coursecontext;
}
}
$rs->close();
return empty($courses) ? false : $courses;
}
/**
* This function finds the roles assigned directly to this context only
* i.e. no parents role
*
* @param object $context
* @return array
*/
function get_roles_on_exact_context($context) {
global $DB;
return $DB->get_records_sql("SELECT r.*
FROM {role_assignments} ra, {role} r
WHERE ra.roleid = r.id AND ra.contextid = ?",
array($context->id));
}
/**
* Switches the current user to another role for the current session and only
* in the given context.
*
* The caller *must* check
* - that this op is allowed
* - that the requested role can be switched to in this context (use get_switchable_roles)
* - that the requested role is NOT $CFG->defaultuserroleid
*
* To "unswitch" pass 0 as the roleid.
*
* This function *will* modify $USER->access - beware
*
* @param integer $roleid the role to switch to.
* @param object $context the context in which to perform the switch.
* @return bool success or failure.
*/
function role_switch($roleid, $context) {
global $USER;
//
// Plan of action
//
// - Add the ghost RA to $USER->access
// as $USER->access['rsw'][$path] = $roleid
//
// - Make sure $USER->access['rdef'] has the roledefs
// it needs to honour the switcherole
//
// Roledefs will get loaded "deep" here - down to the last child
// context. Note that
//
// - When visiting subcontexts, our selective accessdata loading
// will still work fine - though those ra/rdefs will be ignored
// appropriately while the switch is in place
//
// - If a switcherole happens at a category with tons of courses
// (that have many overrides for switched-to role), the session
// will get... quite large. Sometimes you just can't win.
//
// To un-switch just unset($USER->access['rsw'][$path])
//
// Note: it is not possible to switch to roles that do not have course:view
// Add the switch RA
if (!isset($USER->access['rsw'])) {
$USER->access['rsw'] = array();
}
if ($roleid == 0) {
unset($USER->access['rsw'][$context->path]);
if (empty($USER->access['rsw'])) {
unset($USER->access['rsw']);
}
return true;
}
$USER->access['rsw'][$context->path]=$roleid;
// Load roledefs
$USER->access = get_role_access_bycontext($roleid, $context,
$USER->access);
return true;
}
/**
* Checks if the user has switched roles within the given course.
*
* Note: You can only switch roles within the course, hence it takes a courseid
* rather than a context. On that note Petr volunteered to implement this across
* all other contexts, all requests for this should be forwarded to him ;)
*
* @param int $courseid The id of the course to check
* @return bool True if the user has switched roles within the course.
*/
function is_role_switched($courseid) {
global $USER;
$context = get_context_instance(CONTEXT_COURSE, $courseid, MUST_EXIST);
return (!empty($USER->access['rsw'][$context->path]));
}
/**
* Get any role that has an override on exact context
*
* @global moodle_database
* @param stdClass $context The context to check
* @return array An array of roles
*/
function get_roles_with_override_on_context($context) {
global $DB;
return $DB->get_records_sql("SELECT r.*
FROM {role_capabilities} rc, {role} r
WHERE rc.roleid = r.id AND rc.contextid = ?",
array($context->id));
}
/**
* Get all capabilities for this role on this context (overrides)
*
* @param object $role
* @param object $context
* @return array
*/
function get_capabilities_from_role_on_context($role, $context) {
global $DB;
return $DB->get_records_sql("SELECT *
FROM {role_capabilities}
WHERE contextid = ? AND roleid = ?",
array($context->id, $role->id));
}
/**
* Find out which roles has assignment on this context
*
* @param object $context
* @return array
*
*/
function get_roles_with_assignment_on_context($context) {
global $DB;
return $DB->get_records_sql("SELECT r.*
FROM {role_assignments} ra, {role} r
WHERE ra.roleid = r.id AND ra.contextid = ?",
array($context->id));
}
/**
* Find all user assignment of users for this role, on this context
*
* @param object $role
* @param object $context
* @return array
*/
function get_users_from_role_on_context($role, $context) {
global $DB;
return $DB->get_records_sql("SELECT *
FROM {role_assignments}
WHERE contextid = ? AND roleid = ?",
array($context->id, $role->id));
}
/**
* Simple function returning a boolean true if user has roles
* in context or parent contexts, otherwise false.
*
* @param int $userid
* @param int $roleid
* @param int $contextid empty means any context
* @return bool
*/
function user_has_role_assignment($userid, $roleid, $contextid = 0) {
global $DB;
if ($contextid) {
if (!$context = get_context_instance_by_id($contextid)) {
return false;
}
$parents = get_parent_contexts($context, true);
list($contexts, $params) = $DB->get_in_or_equal($parents, SQL_PARAMS_NAMED, 'r');
$params['userid'] = $userid;
$params['roleid'] = $roleid;
$sql = "SELECT COUNT(ra.id)
FROM {role_assignments} ra
WHERE ra.userid = :userid AND ra.roleid = :roleid AND ra.contextid $contexts";
$count = $DB->get_field_sql($sql, $params);
return ($count > 0);
} else {
return $DB->record_exists('role_assignments', array('userid'=>$userid, 'roleid'=>$roleid));
}
}
/**
* Get role name or alias if exists and format the text.
*
* @param object $role role object
* @param object $coursecontext
* @return string name of role in course context
*/
function role_get_name($role, $coursecontext) {
global $DB;
if ($r = $DB->get_record('role_names', array('roleid'=>$role->id, 'contextid'=>$coursecontext->id))) {
return strip_tags(format_string($r->name));
} else {
return strip_tags(format_string($role->name));
}
}
/**
* Prepare list of roles for display, apply aliases and format text
*
* @param array $roleoptions array roleid => rolename or roleid => roleobject
* @param object $context a context
* @return array Array of context-specific role names, or role objexts with a ->localname field added.
*/
function role_fix_names($roleoptions, $context, $rolenamedisplay = ROLENAME_ALIAS) {
global $DB;
// Make sure we are working with an array roleid => name. Normally we
// want to use the unlocalised name if the localised one is not present.
$newnames = array();
foreach ($roleoptions as $rid => $roleorname) {
if ($rolenamedisplay != ROLENAME_ALIAS_RAW) {
if (is_object($roleorname)) {
$newnames[$rid] = $roleorname->name;
} else {
$newnames[$rid] = $roleorname;
}
} else {
$newnames[$rid] = '';
}
}
// If necessary, get the localised names.
if ($rolenamedisplay != ROLENAME_ORIGINAL && !empty($context->id)) {
// Make sure we have a course context.
if ($context->contextlevel == CONTEXT_MODULE) {
if ($parentcontextid = array_shift(get_parent_contexts($context))) {
$context = get_context_instance_by_id($parentcontextid);
}
} else if ($context->contextlevel == CONTEXT_BLOCK) {
do {
if ($parentcontextid = array_shift(get_parent_contexts($context))) {
$context = get_context_instance_by_id($parentcontextid);
}
} while ($parentcontextid && $context->contextlevel != CONTEXT_COURSE);
}
// The get the relevant renames, and use them.
$aliasnames = $DB->get_records('role_names', array('contextid'=>$context->id));
foreach ($aliasnames as $alias) {
if (isset($newnames[$alias->roleid])) {
if ($rolenamedisplay == ROLENAME_ALIAS || $rolenamedisplay == ROLENAME_ALIAS_RAW) {
$newnames[$alias->roleid] = $alias->name;
} else if ($rolenamedisplay == ROLENAME_BOTH) {
$newnames[$alias->roleid] = $alias->name . ' (' . $roleoptions[$alias->roleid] . ')';
}
}
}
}
// Finally, apply format_string and put the result in the right place.
foreach ($roleoptions as $rid => $roleorname) {
if ($rolenamedisplay != ROLENAME_ALIAS_RAW) {
$newnames[$rid] = strip_tags(format_string($newnames[$rid]));
}
if (is_object($roleorname)) {
$roleoptions[$rid]->localname = $newnames[$rid];
} else {
$roleoptions[$rid] = $newnames[$rid];
}
}
return $roleoptions;
}
/**
* Aids in detecting if a new line is required when reading a new capability
*
* This function helps admin/roles/manage.php etc to detect if a new line should be printed
* when we read in a new capability.
* Most of the time, if the 2 components are different we should print a new line, (e.g. course system->rss client)
* but when we are in grade, all reports/import/export capabilities should be together
*
* @param string $cap component string a
* @param string $comp component string b
* @param mixed $contextlevel
* @return bool whether 2 component are in different "sections"
*/
function component_level_changed($cap, $comp, $contextlevel) {
if (strstr($cap->component, '/') && strstr($comp, '/')) {
$compsa = explode('/', $cap->component);
$compsb = explode('/', $comp);
// list of system reports
if (($compsa[0] == 'report') && ($compsb[0] == 'report')) {
return false;
}
// we are in gradebook, still
if (($compsa[0] == 'gradeexport' || $compsa[0] == 'gradeimport' || $compsa[0] == 'gradereport') &&
($compsb[0] == 'gradeexport' || $compsb[0] == 'gradeimport' || $compsb[0] == 'gradereport')) {
return false;
}
if (($compsa[0] == 'coursereport') && ($compsb[0] == 'coursereport')) {
return false;
}
}
return ($cap->component != $comp || $cap->contextlevel != $contextlevel);
}
/**
* Rebuild all related context depth and path caches
*
* @param array $fixcontexts array of contexts, strongtyped
*/
function rebuild_contexts(array $fixcontexts) {
global $DB;
foreach ($fixcontexts as $context) {
if ($context->path) {
mark_context_dirty($context->path);
}
$DB->set_field_select('context', 'depth', 0, "path LIKE '%/$context->id/%'");
$DB->set_field('context', 'depth', 0, array('id'=>$context->id));
}
build_context_path(false);
}
/**
* Populate context.path and context.depth where missing.
*
* @param bool $force force a complete rebuild of the path and depth fields, defaults to false
*/
function build_context_path($force = false) {
global $CFG, $DB, $ACCESSLIB_PRIVATE;
// System context
$sitectx = get_system_context(!$force);
$base = '/'.$sitectx->id;
// Sitecourse
$sitecoursectx = $DB->get_record('context', array('contextlevel'=>CONTEXT_COURSE, 'instanceid'=>SITEID));
if ($force || $sitecoursectx->path !== "$base/{$sitecoursectx->id}") {
$DB->set_field('context', 'path', "$base/{$sitecoursectx->id}", array('id'=>$sitecoursectx->id));
$DB->set_field('context', 'depth', 2, array('id'=>$sitecoursectx->id));
$sitecoursectx = $DB->get_record('context', array('contextlevel'=>CONTEXT_COURSE, 'instanceid'=>SITEID));
}
$ctxemptyclause = " AND (ctx.path IS NULL
OR ctx.depth=0) ";
$emptyclause = " AND ({context}.path IS NULL
OR {context}.depth=0) ";
if ($force) {
$ctxemptyclause = $emptyclause = '';
}
/* MDL-11347:
* - mysql does not allow to use FROM in UPDATE statements
* - using two tables after UPDATE works in mysql, but might give unexpected
* results in pg 8 (depends on configuration)
* - using table alias in UPDATE does not work in pg < 8.2
*
* Different code for each database - mostly for performance reasons
*/
$dbfamily = $DB->get_dbfamily();
if ($dbfamily == 'mysql') {
$updatesql = "UPDATE {context} ct, {context_temp} temp
SET ct.path = temp.path,
ct.depth = temp.depth
WHERE ct.id = temp.id";
} else if ($dbfamily == 'oracle') {
$updatesql = "UPDATE {context} ct
SET (ct.path, ct.depth) =
(SELECT temp.path, temp.depth
FROM {context_temp} temp
WHERE temp.id=ct.id)
WHERE EXISTS (SELECT 'x'
FROM {context_temp} temp
WHERE temp.id = ct.id)";
} else if ($dbfamily == 'postgres' or $dbfamily == 'mssql') {
$updatesql = "UPDATE {context}
SET path = temp.path,
depth = temp.depth
FROM {context_temp} temp
WHERE temp.id={context}.id";
} else {
// sqlite and others
$updatesql = "UPDATE {context}
SET path = (SELECT path FROM {context_temp} WHERE id = {context}.id),
depth = (SELECT depth FROM {context_temp} WHERE id = {context}.id)
WHERE id IN (SELECT id FROM {context_temp})";
}
// Top level categories
$sql = "UPDATE {context}
SET depth=2, path=" . $DB->sql_concat("'$base/'", 'id') . "
WHERE contextlevel=".CONTEXT_COURSECAT."
AND EXISTS (SELECT 'x'
FROM {course_categories} cc
WHERE cc.id = {context}.instanceid
AND cc.depth=1)
$emptyclause";
$DB->execute($sql);
$DB->delete_records('context_temp');
// Deeper categories - one query per depthlevel
$maxdepth = $DB->get_field_sql("SELECT MAX(depth)
FROM {course_categories}");
for ($n=2; $n<=$maxdepth; $n++) {
$sql = "INSERT INTO {context_temp} (id, path, depth)
SELECT ctx.id, ".$DB->sql_concat('pctx.path', "'/'", 'ctx.id').", $n+1
FROM {context} ctx
JOIN {course_categories} c ON ctx.instanceid=c.id
JOIN {context} pctx ON c.parent=pctx.instanceid
WHERE ctx.contextlevel=".CONTEXT_COURSECAT."
AND pctx.contextlevel=".CONTEXT_COURSECAT."
AND c.depth=$n
AND NOT EXISTS (SELECT 'x'
FROM {context_temp} temp
WHERE temp.id = ctx.id)
$ctxemptyclause";
$DB->execute($sql);
// this is needed after every loop
// MDL-11532
$DB->execute($updatesql);
$DB->delete_records('context_temp');
}
// Courses -- except sitecourse
$sql = "INSERT INTO {context_temp} (id, path, depth)
SELECT ctx.id, ".$DB->sql_concat('pctx.path', "'/'", 'ctx.id').", pctx.depth+1
FROM {context} ctx
JOIN {course} c ON ctx.instanceid=c.id
JOIN {context} pctx ON c.category=pctx.instanceid
WHERE ctx.contextlevel=".CONTEXT_COURSE."
AND c.id!=".SITEID."
AND pctx.contextlevel=".CONTEXT_COURSECAT."
AND NOT EXISTS (SELECT 'x'
FROM {context_temp} temp
WHERE temp.id = ctx.id)
$ctxemptyclause";
$DB->execute($sql);
$DB->execute($updatesql);
$DB->delete_records('context_temp');
// Module instances
$sql = "INSERT INTO {context_temp} (id, path, depth)
SELECT ctx.id, ".$DB->sql_concat('pctx.path', "'/'", 'ctx.id').", pctx.depth+1
FROM {context} ctx
JOIN {course_modules} cm ON ctx.instanceid=cm.id
JOIN {context} pctx ON cm.course=pctx.instanceid
WHERE ctx.contextlevel=".CONTEXT_MODULE."
AND pctx.contextlevel=".CONTEXT_COURSE."
AND NOT EXISTS (SELECT 'x'
FROM {context_temp} temp
WHERE temp.id = ctx.id)
$ctxemptyclause";
$DB->execute($sql);
$DB->execute($updatesql);
$DB->delete_records('context_temp');
// User
$sql = "UPDATE {context}
SET depth=2, path=".$DB->sql_concat("'$base/'", 'id')."
WHERE contextlevel=".CONTEXT_USER."
AND EXISTS (SELECT 'x'
FROM {user} u
WHERE u.id = {context}.instanceid)
$emptyclause ";
$DB->execute($sql);
// Blocks
// pctx.path IS NOT NULL prevents fatal problems with broken block instances that point to invalid context parent
$sql = "INSERT INTO {context_temp} (id, path, depth)
SELECT ctx.id, ".$DB->sql_concat('pctx.path', "'/'", 'ctx.id').", pctx.depth+1
FROM {context} ctx
JOIN {block_instances} bi ON ctx.instanceid = bi.id
JOIN {context} pctx ON bi.parentcontextid = pctx.id
WHERE ctx.contextlevel=".CONTEXT_BLOCK."
AND pctx.path IS NOT NULL
AND NOT EXISTS (SELECT 'x'
FROM {context_temp} temp
WHERE temp.id = ctx.id)
$ctxemptyclause";
$DB->execute($sql);
$DB->execute($updatesql);
$DB->delete_records('context_temp');
// reset static course cache - it might have incorrect cached data
$ACCESSLIB_PRIVATE->contexcache->reset();
}
/**
* Update the path field of the context and all dep. subcontexts that follow
*
* Update the path field of the context and
* all the dependent subcontexts that follow
* the move.
*
* The most important thing here is to be as
* DB efficient as possible. This op can have a
* massive impact in the DB.
*
* @param stdClass $current context obj
* @param stdClass $newparent new parent obj
*
*/
function context_moved($context, $newparent) {
global $DB;
$frompath = $context->path;
$newpath = $newparent->path . '/' . $context->id;
$setdepth = '';
if (($newparent->depth +1) != $context->depth) {
$diff = $newparent->depth - $context->depth + 1;
$setdepth = ", depth = depth + $diff";
}
$sql = "UPDATE {context}
SET path = ?
$setdepth
WHERE path = ?";
$params = array($newpath, $frompath);
$DB->execute($sql, $params);
$sql = "UPDATE {context}
SET path = ".$DB->sql_concat("?", $DB->sql_substr("path", strlen($frompath)+1))."
$setdepth
WHERE path LIKE ?";
$params = array($newpath, "{$frompath}/%");
$DB->execute($sql, $params);
mark_context_dirty($frompath);
mark_context_dirty($newpath);
}
/**
* Preloads context information together with instances.
* NOTE: in future this function may return empty strings
* if we implement different caching.
*
* @param string $joinon for example 'u.id'
* @param string $contextlevel context level of instance in $joinon
* @param string $tablealias context table alias
* @return array with two values - select and join part
*/
function context_instance_preload_sql($joinon, $contextlevel, $tablealias) {
$select = ", $tablealias.id AS ctxid, $tablealias.path AS ctxpath, $tablealias.depth AS ctxdepth, $tablealias.contextlevel AS ctxlevel, $tablealias.instanceid AS ctxinstance";
$join = "LEFT JOIN {context} $tablealias ON ($tablealias.instanceid = $joinon AND $tablealias.contextlevel = $contextlevel)";
return array($select, $join);
}
/**
* Preloads context information from db record and strips the cached info.
* The db request has to ontain both the $join and $select from context_instance_preload_sql()
*
* @param object $rec
* @return void (modifies $rec)
*/
function context_instance_preload(stdClass $rec) {
global $ACCESSLIB_PRIVATE;
if (empty($rec->ctxid)) {
// $rec does not have enough data, passed here repeatedly or context does not exist yet
return;
}
// note: in PHP5 the objects are passed by reference, no need to return $rec
$context = new stdClass();
$context->id = $rec->ctxid; unset($rec->ctxid);
$context->path = $rec->ctxpath; unset($rec->ctxpath);
$context->depth = $rec->ctxdepth; unset($rec->ctxdepth);
$context->contextlevel = $rec->ctxlevel; unset($rec->ctxlevel);
$context->instanceid = $rec->ctxinstance; unset($rec->ctxinstance);
$ACCESSLIB_PRIVATE->contexcache->add($context);
}
/**
* Fetch recent dirty contexts to know cheaply whether our $USER->access
* is stale and needs to be reloaded.
*
* Uses cache_flags
* @param int $time
* @return array Array of dirty contexts
*/
function get_dirty_contexts($time) {
return get_cache_flags('accesslib/dirtycontexts', $time-2);
}
/**
* Mark a context as dirty (with timestamp)
* so as to force reloading of the context.
*
* @param string $path context path
*/
function mark_context_dirty($path) {
global $CFG, $ACCESSLIB_PRIVATE;
if (during_initial_install()) {
return;
}
// only if it is a non-empty string
if (is_string($path) && $path !== '') {
set_cache_flag('accesslib/dirtycontexts', $path, 1, time()+$CFG->sessiontimeout);
if (isset($ACCESSLIB_PRIVATE->dirtycontexts)) {
$ACCESSLIB_PRIVATE->dirtycontexts[$path] = 1;
}
}
}
/**
* Will walk the contextpath to answer whether
* the contextpath is dirty
*
* @param array $contexts array of strings
* @param obj|array $dirty Dirty contexts from get_dirty_contexts()
* @return bool
*/
function is_contextpath_dirty($pathcontexts, $dirty) {
$path = '';
foreach ($pathcontexts as $ctx) {
$path = $path.'/'.$ctx;
if (isset($dirty[$path])) {
return true;
}
}
return false;
}
/**
* Fix the roles.sortorder field in the database, so it contains sequential integers,
* and return an array of roleids in order.
*
* @param array $allroles array of roles, as returned by get_all_roles();
* @return array $role->sortorder =-> $role->id with the keys in ascending order.
*/
function fix_role_sortorder($allroles) {
global $DB;
$rolesort = array();
$i = 0;
foreach ($allroles as $role) {
$rolesort[$i] = $role->id;
if ($role->sortorder != $i) {
$r = new stdClass();
$r->id = $role->id;
$r->sortorder = $i;
$DB->update_record('role', $r);
$allroles[$role->id]->sortorder = $i;
}
$i++;
}
return $rolesort;
}
/**
* Switch the sort order of two roles (used in admin/roles/manage.php).
*
* @param object $first The first role. Actually, only ->sortorder is used.
* @param object $second The second role. Actually, only ->sortorder is used.
* @return boolean success or failure
*/
function switch_roles($first, $second) {
global $DB;
$temp = $DB->get_field('role', 'MAX(sortorder) + 1', array());
$result = $DB->set_field('role', 'sortorder', $temp, array('sortorder' => $first->sortorder));
$result = $result && $DB->set_field('role', 'sortorder', $first->sortorder, array('sortorder' => $second->sortorder));
$result = $result && $DB->set_field('role', 'sortorder', $second->sortorder, array('sortorder' => $temp));
return $result;
}
/**
* duplicates all the base definitions of a role
*
* @param object $sourcerole role to copy from
* @param int $targetrole id of role to copy to
*/
function role_cap_duplicate($sourcerole, $targetrole) {
global $DB;
$systemcontext = get_context_instance(CONTEXT_SYSTEM);
$caps = $DB->get_records_sql("SELECT *
FROM {role_capabilities}
WHERE roleid = ? AND contextid = ?",
array($sourcerole->id, $systemcontext->id));
// adding capabilities
foreach ($caps as $cap) {
unset($cap->id);
$cap->roleid = $targetrole;
$DB->insert_record('role_capabilities', $cap);
}
}
/**
* Returns two lists, this can be used to find out if user has capability.
* Having any needed role and no forbidden role in this context means
* user has this capability in this context.
* Use get_role_names_with_cap_in_context() if you need role names to display in the UI
*
* @param object $context
* @param string $capability
* @return array($neededroles, $forbiddenroles)
*/
function get_roles_with_cap_in_context($context, $capability) {
global $DB;
$ctxids = trim($context->path, '/'); // kill leading slash
$ctxids = str_replace('/', ',', $ctxids);
$sql = "SELECT rc.id, rc.roleid, rc.permission, ctx.depth
FROM {role_capabilities} rc
JOIN {context} ctx ON ctx.id = rc.contextid
WHERE rc.capability = :cap AND ctx.id IN ($ctxids)
ORDER BY rc.roleid ASC, ctx.depth DESC";
$params = array('cap'=>$capability);
if (!$capdefs = $DB->get_records_sql($sql, $params)) {
// no cap definitions --> no capability
return array(array(), array());
}
$forbidden = array();
$needed = array();
foreach($capdefs as $def) {
if (isset($forbidden[$def->roleid])) {
continue;
}
if ($def->permission == CAP_PROHIBIT) {
$forbidden[$def->roleid] = $def->roleid;
unset($needed[$def->roleid]);
continue;
}
if (!isset($needed[$def->roleid])) {
if ($def->permission == CAP_ALLOW) {
$needed[$def->roleid] = true;
} else if ($def->permission == CAP_PREVENT) {
$needed[$def->roleid] = false;
}
}
}
unset($capdefs);
// remove all those roles not allowing
foreach($needed as $key=>$value) {
if (!$value) {
unset($needed[$key]);
} else {
$needed[$key] = $key;
}
}
return array($needed, $forbidden);
}
/**
* Returns an array of role IDs that have ALL of the the supplied capabilities
* Uses get_roles_with_cap_in_context(). Returns $allowed minus $forbidden
*
* @param object $context
* @param array $capabilities An array of capabilities
* @return array of roles with all of the required capabilities
*/
function get_roles_with_caps_in_context($context, $capabilities) {
$neededarr = array();
$forbiddenarr = array();
foreach($capabilities as $caprequired) {
list($neededarr[], $forbiddenarr[]) = get_roles_with_cap_in_context($context, $caprequired);
}
$rolesthatcanrate = array();
if (!empty($neededarr)) {
foreach ($neededarr as $needed) {
if (empty($rolesthatcanrate)) {
$rolesthatcanrate = $needed;
} else {
//only want roles that have all caps
$rolesthatcanrate = array_intersect_key($rolesthatcanrate,$needed);
}
}
}
if (!empty($forbiddenarr) && !empty($rolesthatcanrate)) {
foreach ($forbiddenarr as $forbidden) {
//remove any roles that are forbidden any of the caps
$rolesthatcanrate = array_diff($rolesthatcanrate, $forbidden);
}
}
return $rolesthatcanrate;
}
/**
* Returns an array of role names that have ALL of the the supplied capabilities
* Uses get_roles_with_caps_in_context(). Returns $allowed minus $forbidden
*
* @param object $context
* @param array $capabilities An array of capabilities
* @return array of roles with all of the required capabilities
*/
function get_role_names_with_caps_in_context($context, $capabilities) {
global $DB;
$rolesthatcanrate = get_roles_with_caps_in_context($context, $capabilities);
$allroles = array();
$roles = $DB->get_records('role', null, 'sortorder DESC');
foreach ($roles as $roleid=>$role) {
$allroles[$roleid] = $role->name;
}
$rolenames = array();
foreach ($rolesthatcanrate as $r) {
$rolenames[$r] = $allroles[$r];
}
$rolenames = role_fix_names($rolenames, $context);
return $rolenames;
}
/**
* This function verifies the prohibit comes from this context
* and there are no more prohibits in parent contexts.
* @param object $context
* @param string $capability name
* @return bool
*/
function prohibit_is_removable($roleid, $context, $capability) {
global $DB;
$ctxids = trim($context->path, '/'); // kill leading slash
$ctxids = str_replace('/', ',', $ctxids);
$params = array('roleid'=>$roleid, 'cap'=>$capability, 'prohibit'=>CAP_PROHIBIT);
$sql = "SELECT ctx.id
FROM {role_capabilities} rc
JOIN {context} ctx ON ctx.id = rc.contextid
WHERE rc.roleid = :roleid AND rc.permission = :prohibit AND rc.capability = :cap AND ctx.id IN ($ctxids)
ORDER BY ctx.depth DESC";
if (!$prohibits = $DB->get_records_sql($sql, $params)) {
// no prohibits == nothing to remove
return true;
}
if (count($prohibits) > 1) {
// more prohibints can not be removed
return false;
}
return !empty($prohibits[$context->id]);
}
/**
* More user friendly role permission changing,
* it should produce as few overrides as possible.
* @param int $roleid
* @param object $context
* @param string $capname capability name
* @param int $permission
* @return void
*/
function role_change_permission($roleid, $context, $capname, $permission) {
global $DB;
if ($permission == CAP_INHERIT) {
unassign_capability($capname, $roleid, $context->id);
mark_context_dirty($context->path);
return;
}
$ctxids = trim($context->path, '/'); // kill leading slash
$ctxids = str_replace('/', ',', $ctxids);
$params = array('roleid'=>$roleid, 'cap'=>$capname);
$sql = "SELECT ctx.id, rc.permission, ctx.depth
FROM {role_capabilities} rc
JOIN {context} ctx ON ctx.id = rc.contextid
WHERE rc.roleid = :roleid AND rc.capability = :cap AND ctx.id IN ($ctxids)
ORDER BY ctx.depth DESC";
if ($existing = $DB->get_records_sql($sql, $params)) {
foreach($existing as $e) {
if ($e->permission == CAP_PROHIBIT) {
// prohibit can not be overridden, no point in changing anything
return;
}
}
$lowest = array_shift($existing);
if ($lowest->permission == $permission) {
// permission already set in this context or parent - nothing to do
return;
}
if ($existing) {
$parent = array_shift($existing);
if ($parent->permission == $permission) {
// permission already set in parent context or parent - just unset in this context
// we do this because we want as few overrides as possible for performance reasons
unassign_capability($capname, $roleid, $context->id);
mark_context_dirty($context->path);
return;
}
}
} else {
if ($permission == CAP_PREVENT) {
// nothing means role does not have permission
return;
}
}
// assign the needed capability
assign_capability($capname, $permission, $roleid, $context->id, true);
// force cap reloading
mark_context_dirty($context->path);
}