2012-03-13 09:09:04 +01:00

841 lines
34 KiB
PHP

<?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/>.
/**
* Database enrolment plugin.
*
* This plugin synchronises enrolment and roles with external database table.
*
* @package enrol
* @subpackage database
* @copyright 2010 Petr Skoda {@link http://skodak.org}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
/**
* Database enrolment plugin implementation.
* @author Petr Skoda - based on code by Martin Dougiamas, Martin Langhoff and others
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class enrol_database_plugin extends enrol_plugin {
/**
* Is it possible to delete enrol instance via standard UI?
*
* @param object $instance
* @return bool
*/
public function instance_deleteable($instance) {
if (!enrol_is_enabled('database')) {
return true;
}
if (!$this->get_config('dbtype') or !$this->get_config('dbhost') or !$this->get_config('remoteenroltable') or !$this->get_config('remotecoursefield') or !$this->get_config('remoteuserfield')) {
return true;
}
//TODO: connect to external system and make sure no users are to be enrolled in this course
return false;
}
/**
* Does this plugin allow manual unenrolment of a specific user?
* Yes, but only if user suspended...
*
* @param stdClass $instance course enrol instance
* @param stdClass $ue record from user_enrolments table
*
* @return bool - true means user with 'enrol/xxx:unenrol' may unenrol this user, false means nobody may touch this user enrolment
*/
public function allow_unenrol_user(stdClass $instance, stdClass $ue) {
if ($ue->status == ENROL_USER_SUSPENDED) {
return true;
}
return false;
}
/**
* Gets an array of the user enrolment actions
*
* @param course_enrolment_manager $manager
* @param stdClass $ue A user enrolment object
* @return array An array of user_enrolment_actions
*/
public function get_user_enrolment_actions(course_enrolment_manager $manager, $ue) {
$actions = array();
$context = $manager->get_context();
$instance = $ue->enrolmentinstance;
$params = $manager->get_moodlepage()->url->params();
$params['ue'] = $ue->id;
if ($this->allow_unenrol_user($instance, $ue) && has_capability('enrol/database:unenrol', $context)) {
$url = new moodle_url('/enrol/unenroluser.php', $params);
$actions[] = new user_enrolment_action(new pix_icon('t/delete', ''), get_string('unenrol', 'enrol'), $url, array('class'=>'unenrollink', 'rel'=>$ue->id));
}
return $actions;
}
/**
* Forces synchronisation of user enrolments with external database,
* does not create new courses.
*
* @param object $user user record
* @return void
*/
public function sync_user_enrolments($user) {
global $CFG, $DB;
// we do not create courses here intentionally because it requires full sync and is slow
if (!$this->get_config('dbtype') or !$this->get_config('dbhost') or !$this->get_config('remoteenroltable') or !$this->get_config('remotecoursefield') or !$this->get_config('remoteuserfield')) {
return;
}
$table = $this->get_config('remoteenroltable');
$coursefield = strtolower($this->get_config('remotecoursefield'));
$userfield = strtolower($this->get_config('remoteuserfield'));
$rolefield = strtolower($this->get_config('remoterolefield'));
$localrolefield = $this->get_config('localrolefield');
$localuserfield = $this->get_config('localuserfield');
$localcoursefield = $this->get_config('localcoursefield');
$unenrolaction = $this->get_config('unenrolaction');
$defaultrole = $this->get_config('defaultrole');
$ignorehidden = $this->get_config('ignorehiddencourses');
if (!is_object($user) or !property_exists($user, 'id')) {
throw new coding_exception('Invalid $user parameter in sync_user_enrolments()');
}
if (!property_exists($user, $localuserfield)) {
debugging('Invalid $user parameter in sync_user_enrolments(), missing '.$localuserfield);
$user = $DB->get_record('user', array('id'=>$user->id));
}
// create roles mapping
$allroles = get_all_roles();
if (!isset($allroles[$defaultrole])) {
$defaultrole = 0;
}
$roles = array();
foreach ($allroles as $role) {
$roles[$role->$localrolefield] = $role->id;
}
$enrols = array();
$instances = array();
if (!$extdb = $this->db_init()) {
// can not connect to database, sorry
return;
}
// read remote enrols and create instances
$sql = $this->db_get_sql($table, array($userfield=>$user->$localuserfield), array(), false);
if ($rs = $extdb->Execute($sql)) {
if (!$rs->EOF) {
while ($fields = $rs->FetchRow()) {
$fields = array_change_key_case($fields, CASE_LOWER);
$fields = $this->db_decode($fields);
if (empty($fields[$coursefield])) {
// missing course info
continue;
}
if (!$course = $DB->get_record('course', array($localcoursefield=>$fields[$coursefield]), 'id,visible')) {
continue;
}
if (!$course->visible and $ignorehidden) {
continue;
}
if (empty($fields[$rolefield]) or !isset($roles[$fields[$rolefield]])) {
if (!$defaultrole) {
// role is mandatory
continue;
}
$roleid = $defaultrole;
} else {
$roleid = $roles[$fields[$rolefield]];
}
if (empty($enrols[$course->id])) {
$enrols[$course->id] = array();
}
$enrols[$course->id][] = $roleid;
if ($instance = $DB->get_record('enrol', array('courseid'=>$course->id, 'enrol'=>'database'), '*', IGNORE_MULTIPLE)) {
$instances[$course->id] = $instance;
continue;
}
$enrolid = $this->add_instance($course);
$instances[$course->id] = $DB->get_record('enrol', array('id'=>$enrolid));
}
}
$rs->Close();
$extdb->Close();
} else {
// bad luck, something is wrong with the db connection
$extdb->Close();
return;
}
// enrol user into courses and sync roles
foreach ($enrols as $courseid => $roles) {
if (!isset($instances[$courseid])) {
// ignored
continue;
}
$instance = $instances[$courseid];
if ($e = $DB->get_record('user_enrolments', array('userid'=>$user->id, 'enrolid'=>$instance->id))) {
// reenable enrolment when previously disable enrolment refreshed
if ($e->status == ENROL_USER_SUSPENDED) {
$this->update_user_enrol($instance, $user->id, ENROL_USER_ACTIVE);
}
} else {
$roleid = reset($roles);
$this->enrol_user($instance, $user->id, $roleid, 0, 0, ENROL_USER_ACTIVE);
}
if (!$context = get_context_instance(CONTEXT_COURSE, $instance->courseid)) {
//weird
continue;
}
$current = $DB->get_records('role_assignments', array('contextid'=>$context->id, 'userid'=>$user->id, 'component'=>'enrol_database', 'itemid'=>$instance->id), '', 'id, roleid');
$existing = array();
foreach ($current as $r) {
if (in_array($r->roleid, $roles)) {
$existing[$r->roleid] = $r->roleid;
} else {
role_unassign($r->roleid, $user->id, $context->id, 'enrol_database', $instance->id);
}
}
foreach ($roles as $rid) {
if (!isset($existing[$rid])) {
role_assign($rid, $user->id, $context->id, 'enrol_database', $instance->id);
}
}
}
// unenrol as necessary
$sql = "SELECT e.*, c.visible AS cvisible, ue.status AS ustatus
FROM {enrol} e
JOIN {user_enrolments} ue ON ue.enrolid = e.id
JOIN {course} c ON c.id = e.courseid
WHERE ue.userid = :userid AND e.enrol = 'database'";
$rs = $DB->get_recordset_sql($sql, array('userid'=>$user->id));
foreach ($rs as $instance) {
if (!$instance->cvisible and $ignorehidden) {
continue;
}
if (!$context = get_context_instance(CONTEXT_COURSE, $instance->courseid)) {
//weird
continue;
}
if (!empty($enrols[$instance->courseid])) {
// we want this user enrolled
continue;
}
// deal with enrolments removed from external table
if ($unenrolaction == ENROL_EXT_REMOVED_UNENROL) {
// unenrol
$this->unenrol_user($instance, $user->id);
} else if ($unenrolaction == ENROL_EXT_REMOVED_KEEP) {
// keep - only adding enrolments
} else if ($unenrolaction == ENROL_EXT_REMOVED_SUSPEND or $unenrolaction == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
// disable
if ($instance->ustatus != ENROL_USER_SUSPENDED) {
$this->update_user_enrol($instance, $user->id, ENROL_USER_SUSPENDED);
}
if ($unenrolaction == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
role_unassign_all(array('contextid'=>$context->id, 'userid'=>$user->id, 'component'=>'enrol_database', 'itemid'=>$instance->id));
}
}
}
$rs->close();
}
/**
* Forces synchronisation of all enrolments with external database.
*
* @param bool $verbose
* @return int 0 means success, 1 db connect failure, 2 db read failure
*/
public function sync_enrolments($verbose = false) {
global $CFG, $DB;
// we do not create courses here intentionally because it requires full sync and is slow
if (!$this->get_config('dbtype') or !$this->get_config('dbhost') or !$this->get_config('remoteenroltable') or !$this->get_config('remotecoursefield') or !$this->get_config('remoteuserfield')) {
if ($verbose) {
mtrace('User enrolment synchronisation skipped.');
}
return 0;
}
if ($verbose) {
mtrace('Starting user enrolment synchronisation...');
}
if (!$extdb = $this->db_init()) {
mtrace('Error while communicating with external enrolment database');
return 1;
}
// we may need a lot of memory here
@set_time_limit(0);
raise_memory_limit(MEMORY_HUGE);
// second step is to sync instances and users
$table = $this->get_config('remoteenroltable');
$coursefield = strtolower($this->get_config('remotecoursefield'));
$userfield = strtolower($this->get_config('remoteuserfield'));
$rolefield = strtolower($this->get_config('remoterolefield'));
$localrolefield = $this->get_config('localrolefield');
$localuserfield = $this->get_config('localuserfield');
$localcoursefield = $this->get_config('localcoursefield');
$unenrolaction = $this->get_config('unenrolaction');
$defaultrole = $this->get_config('defaultrole');
// create roles mapping
$allroles = get_all_roles();
if (!isset($allroles[$defaultrole])) {
$defaultrole = 0;
}
$roles = array();
foreach ($allroles as $role) {
$roles[$role->$localrolefield] = $role->id;
}
// get a list of courses to be synced that are in external table
$externalcourses = array();
$sql = $this->db_get_sql($table, array(), array($coursefield), true);
if ($rs = $extdb->Execute($sql)) {
if (!$rs->EOF) {
while ($mapping = $rs->FetchRow()) {
$mapping = reset($mapping);
$mapping = $this->db_decode($mapping);
if (empty($mapping)) {
// invalid mapping
continue;
}
$externalcourses[$mapping] = true;
}
}
$rs->Close();
} else {
mtrace('Error reading data from the external enrolment table');
$extdb->Close();
return 2;
}
$preventfullunenrol = empty($externalcourses);
if ($preventfullunenrol and $unenrolaction == ENROL_EXT_REMOVED_UNENROL) {
if ($verbose) {
mtrace(' Preventing unenrolment of all current users, because it might result in major data loss, there has to be at least one record in external enrol table, sorry.');
}
}
// first find all existing courses with enrol instance
$existing = array();
$sql = "SELECT c.id, c.visible, c.$localcoursefield AS mapping, e.id AS enrolid, c.shortname
FROM {course} c
JOIN {enrol} e ON (e.courseid = c.id AND e.enrol = 'database')";
$rs = $DB->get_recordset_sql($sql); // watch out for idnumber duplicates
foreach ($rs as $course) {
if (empty($course->mapping)) {
continue;
}
$existing[$course->mapping] = $course;
}
$rs->close();
// add necessary enrol instances that are not present yet
$params = array();
$localnotempty = "";
if ($localcoursefield !== 'id') {
$localnotempty = "AND c.$localcoursefield <> :lcfe";
$params['lcfe'] = $DB->sql_empty();
}
$sql = "SELECT c.id, c.visible, c.$localcoursefield AS mapping, c.shortname
FROM {course} c
LEFT JOIN {enrol} e ON (e.courseid = c.id AND e.enrol = 'database')
WHERE e.id IS NULL $localnotempty";
$rs = $DB->get_recordset_sql($sql, $params);
foreach ($rs as $course) {
if (empty($course->mapping)) {
continue;
}
if (!isset($externalcourses[$course->mapping])) {
// course not synced
continue;
}
if (isset($existing[$course->mapping])) {
// some duplicate, sorry
continue;
}
$course->enrolid = $this->add_instance($course);
$existing[$course->mapping] = $course;
}
$rs->close();
// free memory
unset($externalcourses);
// sync enrolments
$ignorehidden = $this->get_config('ignorehiddencourses');
$sqlfields = array($userfield);
if ($rolefield) {
$sqlfields[] = $rolefield;
}
foreach ($existing as $course) {
if ($ignorehidden and !$course->visible) {
continue;
}
if (!$instance = $DB->get_record('enrol', array('id'=>$course->enrolid))) {
continue; //weird
}
$context = get_context_instance(CONTEXT_COURSE, $course->id);
// get current list of enrolled users with their roles
$current_roles = array();
$current_status = array();
$user_mapping = array();
$sql = "SELECT u.$localuserfield AS mapping, u.id, ue.status, ue.userid, ra.roleid
FROM {user} u
JOIN {user_enrolments} ue ON (ue.userid = u.id AND ue.enrolid = :enrolid)
JOIN {role_assignments} ra ON (ra.userid = u.id AND ra.itemid = ue.enrolid AND ra.component = 'enrol_database')
WHERE u.deleted = 0";
$params = array('enrolid'=>$instance->id);
if ($localuserfield === 'username') {
$sql .= " AND u.mnethostid = :mnethostid";
$params['mnethostid'] = $CFG->mnet_localhost_id;
}
$rs = $DB->get_recordset_sql($sql, $params);
foreach ($rs as $ue) {
$current_roles[$ue->userid][$ue->roleid] = $ue->roleid;
$current_status[$ue->userid] = $ue->status;
$user_mapping[$ue->mapping] = $ue->userid;
}
$rs->close();
// get list of users that need to be enrolled and their roles
$requested_roles = array();
$sql = $this->db_get_sql($table, array($coursefield=>$course->mapping), $sqlfields);
if ($rs = $extdb->Execute($sql)) {
if (!$rs->EOF) {
if ($localuserfield === 'username') {
$usersearch = array('mnethostid'=>$CFG->mnet_localhost_id, 'deleted' =>0);
}
while ($fields = $rs->FetchRow()) {
$fields = array_change_key_case($fields, CASE_LOWER);
if (empty($fields[$userfield])) {
//user identification is mandatory!
}
$mapping = $fields[$userfield];
if (!isset($user_mapping[$mapping])) {
$usersearch[$localuserfield] = $mapping;
if (!$user = $DB->get_record('user', $usersearch, 'id', IGNORE_MULTIPLE)) {
// user does not exist or was deleted
continue;
}
$user_mapping[$mapping] = $user->id;
$userid = $user->id;
} else {
$userid = $user_mapping[$mapping];
}
if (empty($fields[$rolefield]) or !isset($roles[$fields[$rolefield]])) {
if (!$defaultrole) {
// role is mandatory
continue;
}
$roleid = $defaultrole;
} else {
$roleid = $roles[$fields[$rolefield]];
}
$requested_roles[$userid][$roleid] = $roleid;
}
}
$rs->Close();
} else {
mtrace('Error while communicating with external enrolment database');
$extdb->Close();
return;
}
unset($user_mapping);
// enrol all users and sync roles
foreach ($requested_roles as $userid=>$userroles) {
foreach ($userroles as $roleid) {
if (empty($current_roles[$userid])) {
$this->enrol_user($instance, $userid, $roleid, 0, 0, ENROL_USER_ACTIVE);
$current_roles[$userid][$roleid] = $roleid;
$current_status[$userid] = ENROL_USER_ACTIVE;
if ($verbose) {
mtrace(" enrolling: $userid ==> $course->shortname as ".$allroles[$roleid]->shortname);
}
}
}
// assign extra roles
foreach ($userroles as $roleid) {
if (empty($current_roles[$userid][$roleid])) {
role_assign($roleid, $userid, $context->id, 'enrol_database', $instance->id);
$current_roles[$userid][$roleid] = $roleid;
if ($verbose) {
mtrace(" assigning roles: $userid ==> $course->shortname as ".$allroles[$roleid]->shortname);
}
}
}
// unassign removed roles
foreach($current_roles[$userid] as $cr) {
if (empty($userroles[$cr])) {
role_unassign($cr, $userid, $context->id, 'enrol_database', $instance->id);
unset($current_roles[$userid][$cr]);
if ($verbose) {
mtrace(" unsassigning roles: $userid ==> $course->shortname");
}
}
}
// reenable enrolment when previously disable enrolment refreshed
if ($current_status[$userid] == ENROL_USER_SUSPENDED) {
$this->update_user_enrol($instance, $userid, ENROL_USER_ACTIVE);
if ($verbose) {
mtrace(" unsuspending: $userid ==> $course->shortname");
}
}
}
// deal with enrolments removed from external table
if ($unenrolaction == ENROL_EXT_REMOVED_UNENROL) {
if (!$preventfullunenrol) {
// unenrol
foreach ($current_status as $userid=>$status) {
if (isset($requested_roles[$userid])) {
continue;
}
$this->unenrol_user($instance, $userid);
if ($verbose) {
mtrace(" unenrolling: $userid ==> $course->shortname");
}
}
}
} else if ($unenrolaction == ENROL_EXT_REMOVED_KEEP) {
// keep - only adding enrolments
} else if ($unenrolaction == ENROL_EXT_REMOVED_SUSPEND or $unenrolaction == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
// disable
foreach ($current_status as $userid=>$status) {
if (isset($requested_roles[$userid])) {
continue;
}
if ($status != ENROL_USER_SUSPENDED) {
$this->update_user_enrol($instance, $userid, ENROL_USER_SUSPENDED);
if ($verbose) {
mtrace(" suspending: $userid ==> $course->shortname");
}
}
if ($unenrolaction == ENROL_EXT_REMOVED_SUSPENDNOROLES) {
role_unassign_all(array('contextid'=>$context->id, 'userid'=>$userid, 'component'=>'enrol_database', 'itemid'=>$instance->id));
if ($verbose) {
mtrace(" unsassigning all roles: $userid ==> $course->shortname");
}
}
}
}
}
// close db connection
$extdb->Close();
if ($verbose) {
mtrace('...user enrolment synchronisation finished.');
}
return 0;
}
/**
* Performs a full sync with external database.
*
* First it creates new courses if necessary, then
* enrols and unenrols users.
*
* @param bool $verbose
* @return int 0 means success, 1 db connect failure, 4 db read failure
*/
public function sync_courses($verbose = false) {
global $CFG, $DB;
// make sure we sync either enrolments or courses
if (!$this->get_config('dbtype') or !$this->get_config('dbhost') or !$this->get_config('newcoursetable') or !$this->get_config('newcoursefullname') or !$this->get_config('newcourseshortname')) {
if ($verbose) {
mtrace('Course synchronisation skipped.');
}
return 0;
}
if ($verbose) {
mtrace('Starting course synchronisation...');
}
// we may need a lot of memory here
@set_time_limit(0);
raise_memory_limit(MEMORY_HUGE);
if (!$extdb = $this->db_init()) {
mtrace('Error while communicating with external enrolment database');
return 1;
}
// first create new courses
$table = $this->get_config('newcoursetable');
$fullname = strtolower($this->get_config('newcoursefullname'));
$shortname = strtolower($this->get_config('newcourseshortname'));
$idnumber = strtolower($this->get_config('newcourseidnumber'));
$category = strtolower($this->get_config('newcoursecategory'));
$sqlfields = array($fullname, $shortname);
if ($category) {
$sqlfields[] = $category;
}
if ($idnumber) {
$sqlfields[] = $idnumber;
}
$sql = $this->db_get_sql($table, array(), $sqlfields);
$createcourses = array();
if ($rs = $extdb->Execute($sql)) {
if (!$rs->EOF) {
while ($fields = $rs->FetchRow()) {
$fields = array_change_key_case($fields, CASE_LOWER);
$fields = $this->db_decode($fields);
if (empty($fields[$shortname]) or empty($fields[$fullname])) {
if ($verbose) {
mtrace(' error: invalid external course record, shortname and fullname are mandatory: ' . json_encode($fields)); // hopefully every geek can read JS, right?
}
continue;
}
if ($DB->record_exists('course', array('shortname'=>$fields[$shortname]))) {
// already exists
continue;
}
// allow empty idnumber but not duplicates
if ($idnumber and $fields[$idnumber] !== '' and $fields[$idnumber] !== null and $DB->record_exists('course', array('idnumber'=>$fields[$idnumber]))) {
if ($verbose) {
mtrace(' error: duplicate idnumber, can not create course: '.$fields[$shortname].' ['.$fields[$idnumber].']');
}
continue;
}
if ($category and !$DB->record_exists('course_categories', array('id'=>$fields[$category]))) {
if ($verbose) {
mtrace(' error: invalid category id, can not create course: '.$fields[$shortname]);
}
continue;
}
$course = new stdClass();
$course->fullname = $fields[$fullname];
$course->shortname = $fields[$shortname];
$course->idnumber = $idnumber ? $fields[$idnumber] : NULL;
$course->category = $category ? $fields[$category] : NULL;
$createcourses[] = $course;
}
}
$rs->Close();
} else {
mtrace('Error reading data from the external course table');
$extdb->Close();
return 4;
}
if ($createcourses) {
require_once("$CFG->dirroot/course/lib.php");
$templatecourse = $this->get_config('templatecourse');
$defaultcategory = $this->get_config('defaultcategory');
$template = false;
if ($templatecourse) {
if ($template = $DB->get_record('course', array('shortname'=>$templatecourse))) {
unset($template->id);
unset($template->fullname);
unset($template->shortname);
unset($template->idnumber);
} else {
if ($verbose) {
mtrace(" can not find template for new course!");
}
}
}
if (!$template) {
$courseconfig = get_config('moodlecourse');
$template = new stdClass();
$template->summary = '';
$template->summaryformat = FORMAT_HTML;
$template->format = $courseconfig->format;
$template->numsections = $courseconfig->numsections;
$template->hiddensections = $courseconfig->hiddensections;
$template->newsitems = $courseconfig->newsitems;
$template->showgrades = $courseconfig->showgrades;
$template->showreports = $courseconfig->showreports;
$template->maxbytes = $courseconfig->maxbytes;
$template->groupmode = $courseconfig->groupmode;
$template->groupmodeforce = $courseconfig->groupmodeforce;
$template->visible = $courseconfig->visible;
$template->lang = $courseconfig->lang;
$template->groupmodeforce = $courseconfig->groupmodeforce;
}
if (!$DB->record_exists('course_categories', array('id'=>$defaultcategory))) {
if ($verbose) {
mtrace(" default course category does not exist!");
}
$categories = $DB->get_records('course_categories', array(), 'sortorder', 'id', 0, 1);
$first = reset($categories);
$defaultcategory = $first->id;
}
foreach ($createcourses as $fields) {
$newcourse = clone($template);
$newcourse->fullname = $fields->fullname;
$newcourse->shortname = $fields->shortname;
$newcourse->idnumber = $fields->idnumber;
$newcourse->category = $fields->category ? $fields->category : $defaultcategory;
$c = create_course($newcourse);
if ($verbose) {
mtrace(" creating course: $c->id, $c->fullname, $c->shortname, $c->idnumber, $c->category");
}
}
unset($createcourses);
unset($template);
}
// close db connection
$extdb->Close();
if ($verbose) {
mtrace('...course synchronisation finished.');
}
return 0;
}
protected function db_get_sql($table, array $conditions, array $fields, $distinct = false, $sort = "") {
$fields = $fields ? implode(',', $fields) : "*";
$where = array();
if ($conditions) {
foreach ($conditions as $key=>$value) {
$value = $this->db_encode($this->db_addslashes($value));
$where[] = "$key = '$value'";
}
}
$where = $where ? "WHERE ".implode(" AND ", $where) : "";
$sort = $sort ? "ORDER BY $sort" : "";
$distinct = $distinct ? "DISTINCT" : "";
$sql = "SELECT $distinct $fields
FROM $table
$where
$sort";
return $sql;
}
/**
* Tries to make connection to the external database.
*
* @return null|ADONewConnection
*/
protected function db_init() {
global $CFG;
require_once($CFG->libdir.'/adodb/adodb.inc.php');
// Connect to the external database (forcing new connection)
$extdb = ADONewConnection($this->get_config('dbtype'));
if ($this->get_config('debugdb')) {
$extdb->debug = true;
ob_start(); //start output buffer to allow later use of the page headers
}
$result = $extdb->Connect($this->get_config('dbhost'), $this->get_config('dbuser'), $this->get_config('dbpass'), $this->get_config('dbname'), true);
if (!$result) {
return null;
}
$extdb->SetFetchMode(ADODB_FETCH_ASSOC);
if ($this->get_config('dbsetupsql')) {
$extdb->Execute($this->get_config('dbsetupsql'));
}
return $extdb;
}
protected function db_addslashes($text) {
// using custom made function for now
if ($this->get_config('dbsybasequoting')) {
$text = str_replace('\\', '\\\\', $text);
$text = str_replace(array('\'', '"', "\0"), array('\\\'', '\\"', '\\0'), $text);
} else {
$text = str_replace("'", "''", $text);
}
return $text;
}
protected function db_encode($text) {
$dbenc = $this->get_config('dbencoding');
if (empty($dbenc) or $dbenc == 'utf-8') {
return $text;
}
if (is_array($text)) {
foreach($text as $k=>$value) {
$text[$k] = $this->db_encode($value);
}
return $text;
} else {
return textlib::convert($text, 'utf-8', $dbenc);
}
}
protected function db_decode($text) {
$dbenc = $this->get_config('dbencoding');
if (empty($dbenc) or $dbenc == 'utf-8') {
return $text;
}
if (is_array($text)) {
foreach($text as $k=>$value) {
$text[$k] = $this->db_decode($value);
}
return $text;
} else {
return textlib::convert($text, $dbenc, 'utf-8');
}
}
}