505 lines
18 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/>.
/**
* This plugin is used to access Google Drive.
*
* @since 2.0
* @package repository_googledocs
* @copyright 2009 Dan Poltawski <talktodan@gmail.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
require_once($CFG->dirroot . '/repository/lib.php');
require_once($CFG->libdir . '/textlib.class.php');
require_once($CFG->libdir . '/google/Google_Client.php');
require_once($CFG->libdir . '/google/contrib/Google_DriveService.php');
/**
* Google Docs Plugin
*
* @since 2.0
* @package repository_googledocs
* @copyright 2009 Dan Poltawski <talktodan@gmail.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class repository_googledocs extends repository {
/**
* Google Client.
* @var Google_Client
*/
private $client = null;
/**
* Google Drive Service.
* @var Google_DriveService
*/
private $service = null;
/**
* Session key to store the accesstoken.
* @var string
*/
const SESSIONKEY = 'googledrive_accesstoken';
/**
* URI to the callback file for OAuth.
* @var string
*/
const CALLBACKURL = '/admin/oauth2callback.php';
/**
* Constructor.
*
* @param int $repositoryid repository instance id.
* @param int|stdClass $context a context id or context object.
* @param array $options repository options.
* @param int $readonly indicate this repo is readonly or not.
* @return void
*/
public function __construct($repositoryid, $context = SYSCONTEXTID, $options = array(), $readonly = 0) {
parent::__construct($repositoryid, $context, $options, $readonly = 0);
$callbackurl = new moodle_url(self::CALLBACKURL);
$this->client = new Google_Client();
$this->client->setClientId(get_config('googledocs', 'clientid'));
$this->client->setClientSecret(get_config('googledocs', 'secret'));
$this->client->setScopes(array('https://www.googleapis.com/auth/drive.readonly'));
$this->client->setRedirectUri($callbackurl->out(false));
$this->service = new Google_DriveService($this->client);
$this->check_login();
}
/**
* Returns the access token if any.
*
* @return string|null access token.
*/
protected function get_access_token() {
global $SESSION;
if (isset($SESSION->{self::SESSIONKEY})) {
return $SESSION->{self::SESSIONKEY};
}
return null;
}
/**
* Store the access token in the session.
*
* @param string $token token to store.
* @return void
*/
protected function store_access_token($token) {
global $SESSION;
$SESSION->{self::SESSIONKEY} = $token;
}
/**
* Callback method during authentication.
*
* @return void
*/
public function callback() {
if ($code = optional_param('oauth2code', null, PARAM_RAW)) {
$this->client->authenticate($code);
$this->store_access_token($this->client->getAccessToken());
}
}
/**
* Checks whether the user is authenticate or not.
*
* @return bool true when logged in.
*/
public function check_login() {
if ($token = $this->get_access_token()) {
$this->client->setAccessToken($token);
return true;
}
return false;
}
/**
* Print or return the login form.
*
* @return void|array for ajax.
*/
public function print_login() {
$returnurl = new moodle_url('/repository/repository_callback.php');
$returnurl->param('callback', 'yes');
$returnurl->param('repo_id', $this->id);
$returnurl->param('sesskey', sesskey());
$url = new moodle_url($this->client->createAuthUrl());
$url->param('state', $returnurl->out_as_local_url(false));
if ($this->options['ajax']) {
$popup = new stdClass();
$popup->type = 'popup';
$popup->url = $url->out(false);
return array('login' => array($popup));
} else {
echo '<a target="_blank" href="'.$url->out(false).'">'.get_string('login', 'repository').'</a>';
}
}
/**
* Build the breadcrumb from a path.
*
* @param string $path to create a breadcrumb from.
* @return array containing name and path of each crumb.
*/
protected function build_breadcrumb($path) {
$bread = explode('/', $path);
$crumbtrail = '';
foreach ($bread as $crumb) {
list($id, $name) = $this->explode_node_path($crumb);
$name = empty($name) ? $id : $name;
$breadcrumb[] = array(
'name' => $name,
'path' => $this->build_node_path($id, $name, $crumbtrail)
);
$tmp = end($breadcrumb);
$crumbtrail = $tmp['path'];
}
return $breadcrumb;
}
/**
* Generates a safe path to a node.
*
* Typically, a node will be id|Name of the node.
*
* @param string $id of the node.
* @param string $name of the node, will be URL encoded.
* @param string $root to append the node on, must be a result of this function.
* @return string path to the node.
*/
protected function build_node_path($id, $name = '', $root = '') {
$path = $id;
if (!empty($name)) {
$path .= '|' . urlencode($name);
}
if (!empty($root)) {
$path = trim($root, '/') . '/' . $path;
}
return $path;
}
/**
* Returns information about a node in a path.
*
* @see self::build_node_path()
* @param string $node to extrat information from.
* @return array about the node.
*/
protected function explode_node_path($node) {
if (strpos($node, '|') !== false) {
list($id, $name) = explode('|', $node, 2);
$name = urldecode($name);
} else {
$id = $node;
$name = '';
}
$id = urldecode($id);
return array(
0 => $id,
1 => $name,
'id' => $id,
'name' => $name
);
}
/**
* List the files and folders.
*
* @param string $path path to browse.
* @param string $page page to browse.
* @return array of result.
*/
public function get_listing($path='', $page = '') {
if (empty($path)) {
$path = $this->build_node_path('root', get_string('pluginname', 'repository_googledocs'));
}
// We analyse the path to extract what to browse.
$trail = explode('/', $path);
$uri = array_pop($trail);
list($id, $name) = $this->explode_node_path($uri);
// Handle the special keyword 'search', which we defined in self::search() so that
// we could set up a breadcrumb in the search results. In any other case ID would be
// 'root' which is a special keyword set up by Google, or a parent (folder) ID.
if ($id === 'search') {
return $this->search($name);
}
// Query the Drive.
$q = "'" . str_replace("'", "\'", $id) . "' in parents";
$q .= ' AND trashed = false';
$results = $this->query($q, $path);
$ret = array();
$ret['dynload'] = true;
$ret['path'] = $this->build_breadcrumb($path);
$ret['list'] = $results;
return $ret;
}
/**
* Search throughout the Google Drive.
*
* @param string $search_text text to search for.
* @param int $page search page.
* @return array of results.
*/
public function search($search_text, $page = 0) {
$path = $this->build_node_path('root', get_string('pluginname', 'repository_googledocs'));
$path = $this->build_node_path('search', $search_text, $path);
// Query the Drive.
$q = "fullText contains '" . str_replace("'", "\'", $search_text) . "'";
$q .= ' AND trashed = false';
$results = $this->query($q, $path);
$ret = array();
$ret['dynload'] = true;
$ret['path'] = $this->build_breadcrumb($path);
$ret['list'] = $results;
return $ret;
}
/**
* Query Google Drive for files and folders using a search query.
*
* Documentation about the query format can be found here:
* https://developers.google.com/drive/search-parameters
*
* This returns a list of files and folders with their details as they should be
* formatted and returned by functions such as get_listing() or search().
*
* @param string $q search query as expected by the Google API.
* @param string $path parent path of the current files, will not be used for the query.
* @param int $page page.
* @return array of files and folders.
*/
protected function query($q, $path = null, $page = 0) {
global $OUTPUT;
$files = array();
$folders = array();
$fields = "items(id,title,mimeType,downloadUrl,fileExtension,exportLinks,modifiedDate,fileSize,thumbnailLink)";
$params = array('q' => $q, 'fields' => $fields);
try {
// Retrieving files and folders.
$response = $this->service->files->listFiles($params);
} catch (Google_ServiceException $e) {
if ($e->getCode() == 403 && strpos($e->getMessage(), 'Access Not Configured') !== false) {
// This is raised when the service Drive API has not been enabled on Google APIs control panel.
throw new repository_exception('servicenotenabled', 'repository_googledocs');
} else {
throw $e;
}
}
$items = isset($response['items']) ? $response['items'] : array();
foreach ($items as $item) {
if ($item['mimeType'] == 'application/vnd.google-apps.folder') {
// This is a folder.
$folders[$item['title'] . $item['id']] = array(
'title' => $item['title'],
'path' => $this->build_node_path($item['id'], $item['title'], $path),
'date' => strtotime($item['modifiedDate']),
'thumbnail' => $OUTPUT->pix_url(file_folder_icon(64))->out(false),
'thumbnail_height' => 64,
'thumbnail_width' => 64,
'children' => array()
);
} else {
// This is a file.
if (isset($item['fileExtension'])) {
// The file has an extension, therefore there is a download link.
$title = $item['title'];
$source = $item['downloadUrl'];
} else {
// The file is probably a Google Doc file, we get the corresponding export link.
// This should be improved by allowing the user to select the type of export they'd like.
$type = str_replace('application/vnd.google-apps.', '', $item['mimeType']);
$title = '';
$exportType = '';
switch ($type){
case 'document':
$title = $item['title'] . '.rtf';
$exportType = 'application/rtf';
break;
case 'presentation':
$title = $item['title'] . '.pptx';
$exportType = 'application/vnd.openxmlformats-officedocument.presentationml.presentation';
break;
case 'spreadsheet':
$title = $item['title'] . '.xlsx';
$exportType = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
break;
}
// Skips invalid/unknown types.
if (empty($title) || !isset($item['exportLinks'][$exportType])) {
continue;
}
$source = $item['exportLinks'][$exportType];
}
// Adds the file to the file list. Using the itemId along with the title as key
// of the array because Google Drive allows files with identical names.
$files[$title . $item['id']] = array(
'title' => $title,
'source' => $source,
'date' => strtotime($item['modifiedDate']),
'size' => isset($item['fileSize']) ? $item['fileSize'] : null,
'thumbnail' => $OUTPUT->pix_url(file_extension_icon($title, 64))->out(false),
'thumbnail_height' => 64,
'thumbnail_width' => 64,
// Do not use real thumbnails as they wouldn't work if the user disabled 3rd party
// plugins in his browser, or if they're not logged in their Google account.
);
// Sometimes the real thumbnails can't be displayed, for example if 3rd party cookies are disabled
// or if the user is not logged in Google anymore. But this restriction does not seem to be applied
// to a small subset of files.
$extension = strtolower(pathinfo($title, PATHINFO_EXTENSION));
if (isset($item['thumbnailLink']) && in_array($extension, array('jpg', 'png', 'txt', 'pdf'))) {
$files[$title . $item['id']]['realthumbnail'] = $item['thumbnailLink'];
}
}
}
// Filter and order the results.
$files = array_filter($files, array($this, 'filter'));
collatorlib::ksort($files, collatorlib::SORT_NATURAL);
collatorlib::ksort($folders, collatorlib::SORT_NATURAL);
return array_merge(array_values($folders), array_values($files));
}
/**
* Logout.
*
* @return string
*/
public function logout() {
$this->store_access_token(null);
return parent::logout();
}
/**
* Get a file.
*
* @param string $reference reference of the file.
* @param string $file name to save the file to.
* @return string JSON encoded array of information about the file.
*/
public function get_file($reference, $filename = '') {
$request = new Google_HttpRequest($reference);
$httpRequest = Google_Client::$io->authenticatedRequest($request);
if ($httpRequest->getResponseHttpCode() == 200) {
$path = $this->prepare_file($filename);
$content = $httpRequest->getResponseBody();
if (file_put_contents($path, $content) !== false) {
return array(
'path' => $path,
'url' => $reference
);
}
}
throw new repository_exception('cannotdownload', 'repository');
}
/**
* Prepare file reference information.
*
* We are using this method to clean up the source to make sure that it
* is a valid source.
*
* @param string $source of the file.
* @return string file reference.
*/
public function get_file_reference($source) {
return clean_param($source, PARAM_URL);
}
/**
* What kind of files will be in this repository?
*
* @return array return '*' means this repository support any files, otherwise
* return mimetypes of files, it can be an array
*/
public function supported_filetypes() {
return '*';
}
/**
* Tells how the file can be picked from this repository.
*
* Maximum value is FILE_INTERNAL | FILE_EXTERNAL | FILE_REFERENCE.
*
* @return int
*/
public function supported_returntypes() {
return FILE_INTERNAL;
}
/**
* Return names of the general options.
* By default: no general option name.
*
* @return array
*/
public static function get_type_option_names() {
return array('clientid', 'secret', 'pluginname');
}
/**
* Edit/Create Admin Settings Moodle form.
*
* @param moodleform $mform Moodle form (passed by reference).
* @param string $classname repository class name.
*/
public static function type_config_form($mform, $classname = 'repository') {
$callbackurl = new moodle_url(self::CALLBACKURL);
$a = new stdClass;
$a->docsurl = get_docs_url('Google_OAuth_2.0_setup');
$a->callbackurl = $callbackurl->out(false);
$mform->addElement('static', null, '', get_string('oauthinfo', 'repository_googledocs', $a));
parent::type_config_form($mform);
$mform->addElement('text', 'clientid', get_string('clientid', 'repository_googledocs'));
$mform->setType('clientid', PARAM_RAW_TRIMMED);
$mform->addElement('text', 'secret', get_string('secret', 'repository_googledocs'));
$mform->setType('secret', PARAM_RAW_TRIMMED);
$strrequired = get_string('required');
$mform->addRule('clientid', $strrequired, 'required', null, 'client');
$mform->addRule('secret', $strrequired, 'required', null, 'client');
}
}
// Icon from: http://www.iconspedia.com/icon/google-2706.html.