enrol/category/locallib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * Local stuff for category enrolment plugin.
  20  *
  21  * @package    enrol
  22  * @subpackage category
  23  * @copyright  2010 Petr Skoda {@link http://skodak.org}
  24  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  25  */
  26
  27 defined('MOODLE_INTERNAL') || die();
  28
  29 /**
  30  * Event handler for category enrolment plugin.
  31  *
  32  * We try to keep everything in sync via listening to events,
  33  * it may fail sometimes, so we always do a full sync in cron too.
  34  */
  35 class enrol_category_handler {
  36     public function role_assigned($ra) {
  37         global $DB;
  38
  39         if (!enrol_is_enabled('category')) {
  40             return true;
  41         }
  42
  43         //only category level roles are interesting
  44         $parentcontext = get_context_instance_by_id($ra->contextid);
  45         if ($parentcontext->contextlevel != CONTEXT_COURSECAT) {
  46             return true;
  47         }
  48
  49         // make sure the role is to be actually synchronised
  50         // please note we are ignoring overrides of the synchronised capability (for performance reasons in full sync)
  51         $syscontext = get_context_instance(CONTEXT_SYSTEM);
  52         if (!$DB->record_exists('role_capabilities', array('contextid'=>$syscontext->id, 'roleid'=>$ra->roleid, 'capability'=>'enrol/category:synchronised', 'permission'=>CAP_ALLOW))) {
  53             return true;
  54         }
  55
  56         // add necessary enrol instances
  57         $plugin = enrol_get_plugin('category');
  58         $sql = "SELECT c.*
  59                   FROM {course} c
  60                   JOIN {context} ctx ON (ctx.instanceid = c.id AND ctx.contextlevel = :courselevel AND ctx.path LIKE :match)
  61              LEFT JOIN {enrol} e ON (e.courseid = c.id AND e.enrol = 'category')
  62                  WHERE e.id IS NULL";
  63         $params = array('courselevel'=>CONTEXT_COURSE, 'match'=>$parentcontext->path.'/%');
  64         $rs = $DB->get_recordset_sql($sql, $params);
  65         foreach ($rs as $course) {
  66             $plugin->add_instance($course);
  67         }
  68         $rs->close();
  69
  70         // now look for missing enrols
  71         $sql = "SELECT e.*
  72                   FROM {course} c
  73                   JOIN {context} ctx ON (ctx.instanceid = c.id AND ctx.contextlevel = :courselevel AND ctx.path LIKE :match)
  74                   JOIN {enrol} e ON (e.courseid = c.id AND e.enrol = 'category')
  75              LEFT JOIN {user_enrolments} ue ON (ue.enrolid = e.id AND ue.userid = :userid)
  76                  WHERE ue.id IS NULL";
  77         $params = array('courselevel'=>CONTEXT_COURSE, 'match'=>$parentcontext->path.'/%', 'userid'=>$ra->userid);
  78         $rs = $DB->get_recordset_sql($sql, $params);
  79         foreach ($rs as $instance) {
  80             $plugin->enrol_user($instance, $ra->userid, null, $ra->timemodified);
  81         }
  82         $rs->close();
  83
  84         return true;
  85     }
  86
  87     public function role_unassigned($ra) {
  88         global $DB;
  89
  90         if (!enrol_is_enabled('category')) {
  91             return true;
  92         }
  93
  94         // only category level roles are interesting
  95         $parentcontext = get_context_instance_by_id($ra->contextid);
  96         if ($parentcontext->contextlevel != CONTEXT_COURSECAT) {
  97             return true;
  98         }
  99
 100         // now this is going to be a bit slow, take all enrolments in child courses and verify each separately
 101         $syscontext = get_context_instance(CONTEXT_SYSTEM);
 102         $roles = get_roles_with_capability('enrol/category:synchronised', CAP_ALLOW, $syscontext);
 103
 104         $plugin = enrol_get_plugin('category');
 105
 106         $sql = "SELECT e.*
 107                   FROM {course} c
 108                   JOIN {context} ctx ON (ctx.instanceid = c.id AND ctx.contextlevel = :courselevel AND ctx.path LIKE :match)
 109                   JOIN {enrol} e ON (e.courseid = c.id AND e.enrol = 'category')
 110                   JOIN {user_enrolments} ue ON (ue.enrolid = e.id AND ue.userid = :userid)";
 111         $params = array('courselevel'=>CONTEXT_COURSE, 'match'=>$parentcontext->path.'/%', 'userid'=>$ra->userid);
 112         $rs = $DB->get_recordset_sql($sql, $params);
 113
 114         list($roleids, $params) = $DB->get_in_or_equal(array_keys($roles), SQL_PARAMS_NAMED, 'r');
 115         $params['userid'] = $ra->userid;
 116
 117         foreach ($rs as $instance) {
 118             $coursecontext = get_context_instance(CONTEXT_COURSE, $instance->courseid);
 119             $contextids = get_parent_contexts($coursecontext);
 120             array_pop($contextids); // remove system context, we are interested in categories only
 121
 122             list($contextids, $contextparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED, 'c');
 123             $params = array_merge($params, $contextparams);
 124
 125             $sql = "SELECT ra.id
 126                       FROM {role_assignments} ra
 127                      WHERE ra.userid = :userid AND ra.contextid $contextids AND ra.roleid $roleids";
 128             if (!$DB->record_exists_sql($sql, $params)) {
 129                 // user does not have any interesting role in any parent context, let's unenrol
 130                 $plugin->unenrol_user($instance, $ra->userid);
 131             }
 132         }
 133         $rs->close();
 134
 135         return true;
 136     }
 137 }
 138
 139 /**
 140  * Sync all category enrolments in one course
 141  * @param int $courseid course id
 142  * @return void
 143  */
 144 function enrol_category_sync_course($course) {
 145     global $DB;
 146
 147     if (!enrol_is_enabled('category')) {
 148         return;
 149     }
 150
 151     $plugin = enrol_get_plugin('category');
 152
 153     $syscontext = get_context_instance(CONTEXT_SYSTEM);
 154     $roles = get_roles_with_capability('enrol/category:synchronised', CAP_ALLOW, $syscontext);
 155
 156     if (!$roles) {
 157         //nothing to sync, so remove the instance completely if exists
 158         if ($instances = $DB->get_records('enrol', array('courseid'=>$course->id, 'enrol'=>'category'))) {
 159             foreach ($instances as $instance) {
 160                 $plugin->delete_instance($instance);
 161             }
 162         }
 163         return;
 164     }
 165
 166     // first find out if any parent category context contains interesting role assignments
 167     $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
 168     $contextids = get_parent_contexts($coursecontext);
 169     array_pop($contextids); // remove system context, we are interested in categories only
 170
 171     list($roleids, $params) = $DB->get_in_or_equal(array_keys($roles), SQL_PARAMS_NAMED, 'r');
 172     list($contextids, $contextparams) = $DB->get_in_or_equal($contextids, SQL_PARAMS_NAMED, 'c');
 173     $params = array_merge($params, $contextparams);
 174     $params['courseid'] = $course->id;
 175
 176     $sql = "SELECT 'x'
 177               FROM {role_assignments}
 178              WHERE roleid $roleids AND contextid $contextids";
 179     if (!$DB->record_exists_sql($sql, $params)) {
 180         if ($instances = $DB->get_records('enrol', array('courseid'=>$course->id, 'enrol'=>'category'))) {
 181             // should be max one instance, but anyway
 182             foreach ($instances as $instance) {
 183                 $plugin->delete_instance($instance);
 184             }
 185         }
 186         return;
 187     }
 188
 189     // make sure the enrol instance exists - there should be always only one instance
 190     $delinstances = array();
 191     if ($instances = $DB->get_records('enrol', array('courseid'=>$course->id, 'enrol'=>'category'))) {
 192         $instance = array_shift($instances);
 193         $delinstances = $instances;
 194     } else {
 195         $i = $plugin->add_instance($course);
 196         $instance = $DB->get_record('enrol', array('id'=>$i));
 197     }
 198
 199     // add new enrolments
 200     $sql = "SELECT ra.userid, ra.estart
 201               FROM (SELECT xra.userid, MIN(xra.timemodified) AS estart
 202                       FROM {role_assignments} xra
 203                      WHERE xra.roleid $roleids AND xra.contextid $contextids
 204                   GROUP BY xra.userid
 205                    ) ra
 206          LEFT JOIN {user_enrolments} ue ON (ue.enrolid = :instanceid AND ue.userid = ra.userid)
 207              WHERE ue.id IS NULL";
 208     $params['instanceid'] = $instance->id;
 209     $rs = $DB->get_recordset_sql($sql, $params);
 210     foreach ($rs as $ra) {
 211         $plugin->enrol_user($instance, $ra->userid, null, $ra->estart);
 212     }
 213     $rs->close();
 214
 215     // remove unwanted enrolments
 216     $sql = "SELECT DISTINCT ue.userid
 217               FROM {user_enrolments} ue
 218          LEFT JOIN {role_assignments} ra ON (ra.roleid $roleids AND ra.contextid $contextids AND ra.userid = ue.userid)
 219              WHERE ue.enrolid = :instanceid AND ra.id IS NULL";
 220     $rs = $DB->get_recordset_sql($sql, $params);
 221     foreach ($rs as $ra) {
 222         $plugin->unenrol_user($instance, $ra->userid);
 223     }
 224     $rs->close();
 225
 226     if ($delinstances) {
 227         // we have to do this as the last step in order to prevent temporary unenrolment
 228         foreach ($delinstances as $delinstance) {
 229             $plugin->delete_instance($delinstance);
 230         }
 231     }
 232 }
 233
 234 function enrol_category_sync_full() {
 235     global $DB;
 236
 237
 238     if (!enrol_is_enabled('category')) {
 239         return;
 240     }
 241
 242     // we may need a lot of time here
 243     @set_time_limit(0);
 244
 245     $plugin = enrol_get_plugin('category');
 246
 247     $syscontext = get_context_instance(CONTEXT_SYSTEM);
 248
 249     // any interesting roles worth synchronising?
 250     if (!$roles = get_roles_with_capability('enrol/category:synchronised', CAP_ALLOW, $syscontext)) {
 251         // yay, nothing to do, so let's remove all leftovers
 252         if ($instances = $DB->get_records('enrol', array('enrol'=>'category'))) {
 253             foreach ($instances as $instance) {
 254                 $plugin->delete_instance($instance);
 255             }
 256         }
 257         return;
 258     }
 259
 260     list($roleids, $params) = $DB->get_in_or_equal(array_keys($roles), SQL_PARAMS_NAMED, 'r');
 261     $params['courselevel'] = CONTEXT_COURSE;
 262     $params['catlevel'] = CONTEXT_COURSECAT;
 263
 264     // first of all add necessary enrol instances to all courses
 265     $parentcat = $DB->sql_concat("cat.path", "'/%'");
 266     // need whole course records to be used by add_instance(), use inner view (ci) to
 267     // get distinct records only.
 268     // TODO: Moodle 2.1. Improve enrol API to accept courseid / courserec
 269     $sql = "SELECT c.*
 270               FROM {course} c
 271               JOIN (
 272                 SELECT DISTINCT c.id
 273                   FROM {course} c
 274                   JOIN {context} ctx ON (ctx.instanceid = c.id AND ctx.contextlevel = :courselevel)
 275                   JOIN (SELECT DISTINCT cctx.path
 276                           FROM {course_categories} cc
 277                           JOIN {context} cctx ON (cctx.instanceid = cc.id AND cctx.contextlevel = :catlevel)
 278                           JOIN {role_assignments} ra ON (ra.contextid = cctx.id AND ra.roleid $roleids)
 279                        ) cat ON (ctx.path LIKE $parentcat)
 280              LEFT JOIN {enrol} e ON (e.courseid = c.id AND e.enrol = 'category')
 281                  WHERE e.id IS NULL) ci ON (c.id = ci.id)";
 282
 283     $rs = $DB->get_recordset_sql($sql, $params);
 284     foreach($rs as $course) {
 285         $plugin->add_instance($course);
 286     }
 287     $rs->close();
 288
 289     // now look for courses that do not have any interesting roles in parent contexts,
 290     // but still have the instance and delete them
 291     $sql = "SELECT e.*
 292               FROM {enrol} e
 293               JOIN {context} ctx ON (ctx.instanceid = e.courseid AND ctx.contextlevel = :courselevel)
 294          LEFT JOIN (SELECT DISTINCT cctx.path
 295                       FROM {course_categories} cc
 296                       JOIN {context} cctx ON (cctx.instanceid = cc.id AND cctx.contextlevel = :catlevel)
 297                       JOIN {role_assignments} ra ON (ra.contextid = cctx.id AND ra.roleid $roleids)
 298                    ) cat ON (ctx.path LIKE $parentcat)
 299              WHERE e.enrol = 'category' AND cat.path IS NULL";
 300
 301     $rs = $DB->get_recordset_sql($sql, $params);
 302     foreach($rs as $instance) {
 303         $plugin->delete_instance($instance);
 304     }
 305     $rs->close();
 306
 307     // add missing enrolments
 308     $sql = "SELECT e.*, cat.userid, cat.estart
 309               FROM {enrol} e
 310               JOIN {context} ctx ON (ctx.instanceid = e.courseid AND ctx.contextlevel = :courselevel)
 311               JOIN (SELECT cctx.path, ra.userid, MIN(ra.timemodified) AS estart
 312                       FROM {course_categories} cc
 313                       JOIN {context} cctx ON (cctx.instanceid = cc.id AND cctx.contextlevel = :catlevel)
 314                       JOIN {role_assignments} ra ON (ra.contextid = cctx.id AND ra.roleid $roleids)
 315                   GROUP BY cctx.path, ra.userid
 316                    ) cat ON (ctx.path LIKE $parentcat)
 317          LEFT JOIN {user_enrolments} ue ON (ue.enrolid = e.id AND ue.userid = cat.userid)
 318              WHERE e.enrol = 'category' AND ue.id IS NULL";
 319     $rs = $DB->get_recordset_sql($sql, $params);
 320     foreach($rs as $instance) {
 321         $userid = $instance->userid;
 322         $estart = $instance->estart;
 323         unset($instance->userid);
 324         unset($instance->estart);
 325         $plugin->enrol_user($instance, $userid, null, $estart);
 326     }
 327     $rs->close();
 328
 329     // remove stale enrolments
 330     $sql = "SELECT e.*, ue.userid
 331               FROM {enrol} e
 332               JOIN {context} ctx ON (ctx.instanceid = e.courseid AND ctx.contextlevel = :courselevel)
 333               JOIN {user_enrolments} ue ON (ue.enrolid = e.id)
 334          LEFT JOIN (SELECT DISTINCT cctx.path, ra.userid
 335                       FROM {course_categories} cc
 336                       JOIN {context} cctx ON (cctx.instanceid = cc.id AND cctx.contextlevel = :catlevel)
 337                       JOIN {role_assignments} ra ON (ra.contextid = cctx.id AND ra.roleid $roleids)
 338                    ) cat ON (ctx.path LIKE $parentcat AND cat.userid = ue.userid)
 339              WHERE e.enrol = 'category' AND cat.userid IS NULL";
 340     $rs = $DB->get_recordset_sql($sql, $params);
 341     foreach($rs as $instance) {
 342         $userid = $instance->userid;
 343         unset($instance->userid);
 344         $plugin->unenrol_user($instance, $userid);
 345     }
 346     $rs->close();
 347 }