lib/messagelib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Functions for interacting with the message system
  19  *
  20  * @package   core_message
  21  * @copyright 2008 Luis Rodrigues and Martin Dougiamas
  22  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 defined('MOODLE_INTERNAL') || die();
  26
  27 require_once(dirname(dirname(__FILE__)) . '/message/lib.php');
  28
  29 /**
  30  * Called when a message provider wants to send a message.
  31  * This functions checks the message recipient's message processor configuration then
  32  * sends the message to the configured processors
  33  *
  34  * Required parameters of the $eventdata object:
  35  *  component string component name. must exist in message_providers
  36  *  name string message type name. must exist in message_providers
  37  *  userfrom object|int the user sending the message
  38  *  userto object|int the message recipient
  39  *  subject string the message subject
  40  *  fullmessage string the full message in a given format
  41  *  fullmessageformat int the format if the full message (FORMAT_MOODLE, FORMAT_HTML, ..)
  42  *  fullmessagehtml string the full version (the message processor will choose with one to use)
  43  *  smallmessage string the small version of the message
  44  *
  45  * Optional parameters of the $eventdata object:
  46  *  notification bool should the message be considered as a notification rather than a personal message
  47  *  contexturl string if this is a notification then you can specify a url to view the event. For example the forum post the user is being notified of.
  48  *  contexturlname string the display text for contexturl
  49  *
  50  * @category message
  51  * @param object $eventdata information about the message (component, userfrom, userto, ...)
  52  * @return mixed the integer ID of the new message or false if there was a problem with a processor
  53  */
  54 function message_send($eventdata) {
  55     global $CFG, $DB;
  56
  57     //new message ID to return
  58     $messageid = false;
  59
  60     // Fetch default (site) preferences
  61     $defaultpreferences = get_message_output_default_preferences();
  62     $preferencebase = $eventdata->component.'_'.$eventdata->name;
  63     // If message provider is disabled then don't do any processing.
  64     if (!empty($defaultpreferences->{$preferencebase.'_disable'})) {
  65         return $messageid;
  66     }
  67
  68     //TODO: we need to solve problems with database transactions here somehow, for now we just prevent transactions - sorry
  69     $DB->transactions_forbidden();
  70
  71     if (is_number($eventdata->userto)) {
  72         $eventdata->userto = core_user::get_user($eventdata->userto);
  73     }
  74     if (is_int($eventdata->userfrom)) {
  75         $eventdata->userfrom = core_user::get_user($eventdata->userfrom);
  76     }
  77
  78     $usertoisrealuser = (core_user::is_real_user($eventdata->userto->id) != false);
  79     // If recipient is internal user (noreply user), and emailstop is set then don't send any msg.
  80     if (!$usertoisrealuser && !empty($eventdata->userto->emailstop)) {
  81         debugging('Attempt to send msg to internal (noreply) user', DEBUG_NORMAL);
  82         return false;
  83     }
  84
  85     if (!isset($eventdata->userto->auth) or !isset($eventdata->userto->suspended) or !isset($eventdata->userto->deleted)) {
  86         $eventdata->userto = core_user::get_user($eventdata->userto->id);
  87     }
  88
  89     //after how long inactive should the user be considered logged off?
  90     if (isset($CFG->block_online_users_timetosee)) {
  91         $timetoshowusers = $CFG->block_online_users_timetosee * 60;
  92     } else {
  93         $timetoshowusers = 300;//5 minutes
  94     }
  95
  96     // Work out if the user is logged in or not
  97     if (!empty($eventdata->userto->lastaccess) && (time()-$timetoshowusers) < $eventdata->userto->lastaccess) {
  98         $userstate = 'loggedin';
  99     } else {
 100         $userstate = 'loggedoff';
 101     }
 102
 103     // Create the message object
 104     $savemessage = new stdClass();
 105     $savemessage->useridfrom        = $eventdata->userfrom->id;
 106     $savemessage->useridto          = $eventdata->userto->id;
 107     $savemessage->subject           = $eventdata->subject;
 108     $savemessage->fullmessage       = $eventdata->fullmessage;
 109     $savemessage->fullmessageformat = $eventdata->fullmessageformat;
 110     $savemessage->fullmessagehtml   = $eventdata->fullmessagehtml;
 111     $savemessage->smallmessage      = $eventdata->smallmessage;
 112
 113     if (!empty($eventdata->notification)) {
 114         $savemessage->notification = $eventdata->notification;
 115     } else {
 116         $savemessage->notification = 0;
 117     }
 118
 119     if (!empty($eventdata->contexturl)) {
 120         $savemessage->contexturl = $eventdata->contexturl;
 121     } else {
 122         $savemessage->contexturl = null;
 123     }
 124
 125     if (!empty($eventdata->contexturlname)) {
 126         $savemessage->contexturlname = $eventdata->contexturlname;
 127     } else {
 128         $savemessage->contexturlname = null;
 129     }
 130
 131     $savemessage->timecreated = time();
 132
 133     if (PHPUNIT_TEST and class_exists('phpunit_util')) {
 134         // Add some more tests to make sure the normal code can actually work.
 135         $componentdir = core_component::get_component_directory($eventdata->component);
 136         if (!$componentdir or !is_dir($componentdir)) {
 137             throw new coding_exception('Invalid component specified in message-send(): '.$eventdata->component);
 138         }
 139         if (!file_exists("$componentdir/db/messages.php")) {
 140             throw new coding_exception("$eventdata->component does not contain db/messages.php necessary for message_send()");
 141         }
 142         $messageproviders = null;
 143         include("$componentdir/db/messages.php");
 144         if (!isset($messageproviders[$eventdata->name])) {
 145             throw new coding_exception("Missing messaging defaults for event '$eventdata->name' in '$eventdata->component' messages.php file");
 146         }
 147         unset($componentdir);
 148         unset($messageproviders);
 149         // Now ask phpunit if it wants to catch this message.
 150         if (phpunit_util::is_redirecting_messages()) {
 151             $savemessage->timeread = time();
 152             $messageid = $DB->insert_record('message_read', $savemessage);
 153             $message = $DB->get_record('message_read', array('id'=>$messageid));
 154             phpunit_util::message_sent($message);
 155             return $messageid;
 156         }
 157     }
 158
 159     // Fetch enabled processors
 160     $processors = get_message_processors(true);
 161
 162     // Preset variables
 163     $processorlist = array();
 164     // Fill in the array of processors to be used based on default and user preferences
 165     foreach ($processors as $processor) {
 166         // Skip adding processors for internal user, if processor doesn't support sending message to internal user.
 167         if (!$usertoisrealuser && !$processor->object->can_send_to_any_users()) {
 168             continue;
 169         }
 170
 171         // First find out permissions
 172         $defaultpreference = $processor->name.'_provider_'.$preferencebase.'_permitted';
 173         if (isset($defaultpreferences->{$defaultpreference})) {
 174             $permitted = $defaultpreferences->{$defaultpreference};
 175         } else {
 176             // MDL-25114 They supplied an $eventdata->component $eventdata->name combination which doesn't
 177             // exist in the message_provider table (thus there is no default settings for them).
 178             $preferrormsg = "Could not load preference $defaultpreference. Make sure the component and name you supplied
 179                     to message_send() are valid.";
 180             throw new coding_exception($preferrormsg);
 181         }
 182
 183         // Find out if user has configured this output
 184         // Some processors cannot function without settings from the user
 185         $userisconfigured = $processor->object->is_user_configured($eventdata->userto);
 186
 187         // DEBUG: notify if we are forcing unconfigured output
 188         if ($permitted == 'forced' && !$userisconfigured) {
 189             debugging('Attempt to force message delivery to user who has "'.$processor->name.'" output unconfigured', DEBUG_NORMAL);
 190         }
 191
 192         // Warn developers that necessary data is missing regardless of how the processors are configured
 193         if (!isset($eventdata->userto->emailstop)) {
 194             debugging('userto->emailstop is not set. Retrieving it from the user table');
 195             $eventdata->userto->emailstop = $DB->get_field('user', 'emailstop', array('id'=>$eventdata->userto->id));
 196         }
 197
 198         // Populate the list of processors we will be using
 199         if ($permitted == 'forced' && $userisconfigured) {
 200             // An admin is forcing users to use this message processor. Use this processor unconditionally.
 201             $processorlist[] = $processor->name;
 202         } else if ($permitted == 'permitted' && $userisconfigured && !$eventdata->userto->emailstop) {
 203             // User has not disabled notifications
 204             // See if user set any notification preferences, otherwise use site default ones
 205             $userpreferencename = 'message_provider_'.$preferencebase.'_'.$userstate;
 206             if ($userpreference = get_user_preferences($userpreferencename, null, $eventdata->userto->id)) {
 207                 if (in_array($processor->name, explode(',', $userpreference))) {
 208                     $processorlist[] = $processor->name;
 209                 }
 210             } else if (isset($defaultpreferences->{$userpreferencename})) {
 211                 if (in_array($processor->name, explode(',', $defaultpreferences->{$userpreferencename}))) {
 212                     $processorlist[] = $processor->name;
 213                 }
 214             }
 215         }
 216     }
 217
 218     if (empty($processorlist) && $savemessage->notification) {
 219         //if they have deselected all processors and its a notification mark it read. The user doesnt want to be bothered
 220         $savemessage->timeread = time();
 221         $messageid = $DB->insert_record('message_read', $savemessage);
 222     } else {                        // Process the message
 223         // Store unread message just in case we can not send it
 224         $messageid = $savemessage->id = $DB->insert_record('message', $savemessage);
 225         $eventdata->savedmessageid = $savemessage->id;
 226
 227         // Try to deliver the message to each processor
 228         if (!empty($processorlist)) {
 229             foreach ($processorlist as $procname) {
 230                 if (!$processors[$procname]->object->send_message($eventdata)) {
 231                     debugging('Error calling message processor '.$procname);
 232                     $messageid = false;
 233                 }
 234             }
 235
 236             //if messaging is disabled and they previously had forum notifications handled by the popup processor
 237             //or any processor that puts a row in message_working then the notification will remain forever
 238             //unread. To prevent this mark the message read if messaging is disabled
 239             if (empty($CFG->messaging)) {
 240                 require_once($CFG->dirroot.'/message/lib.php');
 241                 $messageid = message_mark_message_read($savemessage, time());
 242             } else if ( $DB->count_records('message_working', array('unreadmessageid' => $savemessage->id)) == 0){
 243                 //if there is no more processors that want to process this we can move message to message_read
 244                 require_once($CFG->dirroot.'/message/lib.php');
 245                 $messageid = message_mark_message_read($savemessage, time(), true);
 246             }
 247         }
 248     }
 249
 250     return $messageid;
 251 }
 252
 253
 254 /**
 255  * Updates the message_providers table with the current set of message providers
 256  *
 257  * @param string $component For example 'moodle', 'mod_forum' or 'block_quiz_results'
 258  * @return boolean True on success
 259  */
 260 function message_update_providers($component='moodle') {
 261     global $DB;
 262
 263     // load message providers from files
 264     $fileproviders = message_get_providers_from_file($component);
 265
 266     // load message providers from the database
 267     $dbproviders = message_get_providers_from_db($component);
 268
 269     foreach ($fileproviders as $messagename => $fileprovider) {
 270
 271         if (!empty($dbproviders[$messagename])) {   // Already exists in the database
 272             // check if capability has changed
 273             if ($dbproviders[$messagename]->capability == $fileprovider['capability']) {  // Same, so ignore
 274                 // exact same message provider already present in db, ignore this entry
 275                 unset($dbproviders[$messagename]);
 276                 continue;
 277
 278             } else {                                // Update existing one
 279                 $provider = new stdClass();
 280                 $provider->id         = $dbproviders[$messagename]->id;
 281                 $provider->capability = $fileprovider['capability'];
 282                 $DB->update_record('message_providers', $provider);
 283                 unset($dbproviders[$messagename]);
 284                 continue;
 285             }
 286
 287         } else {             // New message provider, add it
 288
 289             $provider = new stdClass();
 290             $provider->name       = $messagename;
 291             $provider->component  = $component;
 292             $provider->capability = $fileprovider['capability'];
 293
 294             $transaction = $DB->start_delegated_transaction();
 295             $DB->insert_record('message_providers', $provider);
 296             message_set_default_message_preference($component, $messagename, $fileprovider);
 297             $transaction->allow_commit();
 298         }
 299     }
 300
 301     foreach ($dbproviders as $dbprovider) {  // Delete old ones
 302         $DB->delete_records('message_providers', array('id' => $dbprovider->id));
 303         $DB->delete_records_select('config_plugins', "plugin = 'message' AND ".$DB->sql_like('name', '?', false), array("%_provider_{$component}_{$dbprovider->name}_%"));
 304         $DB->delete_records_select('user_preferences', $DB->sql_like('name', '?', false), array("message_provider_{$component}_{$dbprovider->name}_%"));
 305         cache_helper::invalidate_by_definition('core', 'config', array(), 'message');
 306     }
 307
 308     return true;
 309 }
 310
 311 /**
 312  * This function populates default message preferences for all existing providers
 313  * when the new message processor is added.
 314  *
 315  * @param string $processorname The name of message processor plugin (e.g. 'email', 'jabber')
 316  * @throws invalid_parameter_exception if $processorname does not exist in the database
 317  */
 318 function message_update_processors($processorname) {
 319     global $DB;
 320
 321     // validate if our processor exists
 322     $processor = $DB->get_records('message_processors', array('name' => $processorname));
 323     if (empty($processor)) {
 324         throw new invalid_parameter_exception();
 325     }
 326
 327     $providers = $DB->get_records_sql('SELECT DISTINCT component FROM {message_providers}');
 328
 329     $transaction = $DB->start_delegated_transaction();
 330     foreach ($providers as $provider) {
 331         // load message providers from files
 332         $fileproviders = message_get_providers_from_file($provider->component);
 333         foreach ($fileproviders as $messagename => $fileprovider) {
 334             message_set_default_message_preference($provider->component, $messagename, $fileprovider, $processorname);
 335         }
 336     }
 337     $transaction->allow_commit();
 338 }
 339
 340 /**
 341  * Setting default messaging preferences for particular message provider
 342  *
 343  * @param  string $component   The name of component (e.g. moodle, mod_forum, etc.)
 344  * @param  string $messagename The name of message provider
 345  * @param  array  $fileprovider The value of $messagename key in the array defined in plugin messages.php
 346  * @param  string $processorname The optional name of message processor
 347  */
 348 function message_set_default_message_preference($component, $messagename, $fileprovider, $processorname='') {
 349     global $DB;
 350
 351     // Fetch message processors
 352     $condition = null;
 353     // If we need to process a particular processor, set the select condition
 354     if (!empty($processorname)) {
 355        $condition = array('name' => $processorname);
 356     }
 357     $processors = $DB->get_records('message_processors', $condition);
 358
 359     // load default messaging preferences
 360     $defaultpreferences = get_message_output_default_preferences();
 361
 362     // Setting default preference
 363     $componentproviderbase = $component.'_'.$messagename;
 364     $loggedinpref = array();
 365     $loggedoffpref = array();
 366     // set 'permitted' preference first for each messaging processor
 367     foreach ($processors as $processor) {
 368         $preferencename = $processor->name.'_provider_'.$componentproviderbase.'_permitted';
 369         // if we do not have this setting yet, set it
 370         if (!isset($defaultpreferences->{$preferencename})) {
 371             // determine plugin default settings
 372             $plugindefault = 0;
 373             if (isset($fileprovider['defaults'][$processor->name])) {
 374                 $plugindefault = $fileprovider['defaults'][$processor->name];
 375             }
 376             // get string values of the settings
 377             list($permitted, $loggedin, $loggedoff) = translate_message_default_setting($plugindefault, $processor->name);
 378             // store default preferences for current processor
 379             set_config($preferencename, $permitted, 'message');
 380             // save loggedin/loggedoff settings
 381             if ($loggedin) {
 382                 $loggedinpref[] = $processor->name;
 383             }
 384             if ($loggedoff) {
 385                 $loggedoffpref[] = $processor->name;
 386             }
 387         }
 388     }
 389     // now set loggedin/loggedoff preferences
 390     if (!empty($loggedinpref)) {
 391         $preferencename = 'message_provider_'.$componentproviderbase.'_loggedin';
 392         if (isset($defaultpreferences->{$preferencename})) {
 393             // We have the default preferences for this message provider, which
 394             // likely means that we have been adding a new processor. Add defaults
 395             // to exisitng preferences.
 396             $loggedinpref = array_merge($loggedinpref, explode(',', $defaultpreferences->{$preferencename}));
 397         }
 398         set_config($preferencename, join(',', $loggedinpref), 'message');
 399     }
 400     if (!empty($loggedoffpref)) {
 401         $preferencename = 'message_provider_'.$componentproviderbase.'_loggedoff';
 402         if (isset($defaultpreferences->{$preferencename})) {
 403             // We have the default preferences for this message provider, which
 404             // likely means that we have been adding a new processor. Add defaults
 405             // to exisitng preferences.
 406             $loggedoffpref = array_merge($loggedoffpref, explode(',', $defaultpreferences->{$preferencename}));
 407         }
 408         set_config($preferencename, join(',', $loggedoffpref), 'message');
 409     }
 410 }
 411
 412 /**
 413  * Returns the active providers for the user specified, based on capability
 414  *
 415  * @param int $userid id of user
 416  * @return array An array of message providers
 417  */
 418 function message_get_providers_for_user($userid) {
 419     global $DB, $CFG;
 420
 421     $providers = get_message_providers();
 422
 423     // Ensure user is not allowed to configure instantmessage if it is globally disabled.
 424     if (!$CFG->messaging) {
 425         foreach ($providers as $providerid => $provider) {
 426             if ($provider->name == 'instantmessage') {
 427                 unset($providers[$providerid]);
 428                 break;
 429             }
 430         }
 431     }
 432
 433     // If the component is an enrolment plugin, check it is enabled
 434     foreach ($providers as $providerid => $provider) {
 435         list($type, $name) = core_component::normalize_component($provider->component);
 436         if ($type == 'enrol' && !enrol_is_enabled($name)) {
 437             unset($providers[$providerid]);
 438         }
 439     }
 440
 441     // Now we need to check capabilities. We need to eliminate the providers
 442     // where the user does not have the corresponding capability anywhere.
 443     // Here we deal with the common simple case of the user having the
 444     // capability in the system context. That handles $CFG->defaultuserroleid.
 445     // For the remaining providers/capabilities, we need to do a more complex
 446     // query involving all overrides everywhere.
 447     $unsureproviders = array();
 448     $unsurecapabilities = array();
 449     $systemcontext = context_system::instance();
 450     foreach ($providers as $providerid => $provider) {
 451         if (empty($provider->capability) || has_capability($provider->capability, $systemcontext, $userid)) {
 452             // The provider is relevant to this user.
 453             continue;
 454         }
 455
 456         $unsureproviders[$providerid] = $provider;
 457         $unsurecapabilities[$provider->capability] = 1;
 458         unset($providers[$providerid]);
 459     }
 460
 461     if (empty($unsureproviders)) {
 462         // More complex checks are not required.
 463         return $providers;
 464     }
 465
 466     // Now check the unsure capabilities.
 467     list($capcondition, $params) = $DB->get_in_or_equal(
 468             array_keys($unsurecapabilities), SQL_PARAMS_NAMED);
 469     $params['userid'] = $userid;
 470
 471     $sql = "SELECT DISTINCT rc.capability, 1
 472
 473               FROM {role_assignments} ra
 474               JOIN {context} actx ON actx.id = ra.contextid
 475               JOIN {role_capabilities} rc ON rc.roleid = ra.roleid
 476               JOIN {context} cctx ON cctx.id = rc.contextid
 477
 478              WHERE ra.userid = :userid
 479                AND rc.capability $capcondition
 480                AND rc.permission > 0
 481                AND (".$DB->sql_concat('actx.path', "'/'")." LIKE ".$DB->sql_concat('cctx.path', "'/%'").
 482                " OR ".$DB->sql_concat('cctx.path', "'/'")." LIKE ".$DB->sql_concat('actx.path', "'/%'").")";
 483
 484     if (!empty($CFG->defaultfrontpageroleid)) {
 485         $frontpagecontext = context_course::instance(SITEID);
 486
 487         list($capcondition2, $params2) = $DB->get_in_or_equal(
 488                 array_keys($unsurecapabilities), SQL_PARAMS_NAMED);
 489         $params = array_merge($params, $params2);
 490         $params['frontpageroleid'] = $CFG->defaultfrontpageroleid;
 491         $params['frontpagepathpattern'] = $frontpagecontext->path . '/';
 492
 493         $sql .= "
 494              UNION
 495
 496             SELECT DISTINCT rc.capability, 1
 497
 498               FROM {role_capabilities} rc
 499               JOIN {context} cctx ON cctx.id = rc.contextid
 500
 501              WHERE rc.roleid = :frontpageroleid
 502                AND rc.capability $capcondition2
 503                AND rc.permission > 0
 504                AND ".$DB->sql_concat('cctx.path', "'/'")." LIKE :frontpagepathpattern";
 505     }
 506
 507     $relevantcapabilities = $DB->get_records_sql_menu($sql, $params);
 508
 509     // Add back any providers based on the detailed capability check.
 510     foreach ($unsureproviders as $providerid => $provider) {
 511         if (array_key_exists($provider->capability, $relevantcapabilities)) {
 512             $providers[$providerid] = $provider;
 513         }
 514     }
 515
 516     return $providers;
 517 }
 518
 519 /**
 520  * Gets the message providers that are in the database for this component.
 521  *
 522  * This is an internal function used within messagelib.php
 523  *
 524  * @see message_update_providers()
 525  * @param string $component A moodle component like 'moodle', 'mod_forum', 'block_quiz_results'
 526  * @return array An array of message providers
 527  */
 528 function message_get_providers_from_db($component) {
 529     global $DB;
 530
 531     return $DB->get_records('message_providers', array('component'=>$component), '', 'name, id, component, capability');  // Name is unique per component
 532 }
 533
 534 /**
 535  * Loads the messages definitions for a component from file
 536  *
 537  * If no messages are defined for the component, return an empty array.
 538  * This is an internal function used within messagelib.php
 539  *
 540  * @see message_update_providers()
 541  * @see message_update_processors()
 542  * @param string $component A moodle component like 'moodle', 'mod_forum', 'block_quiz_results'
 543  * @return array An array of message providers or empty array if not exists
 544  */
 545 function message_get_providers_from_file($component) {
 546     $defpath = core_component::get_component_directory($component).'/db/messages.php';
 547
 548     $messageproviders = array();
 549
 550     if (file_exists($defpath)) {
 551         require($defpath);
 552     }
 553
 554     foreach ($messageproviders as $name => $messageprovider) {   // Fix up missing values if required
 555         if (empty($messageprovider['capability'])) {
 556             $messageproviders[$name]['capability'] = NULL;
 557         }
 558         if (empty($messageprovider['defaults'])) {
 559             $messageproviders[$name]['defaults'] = array();
 560         }
 561     }
 562
 563     return $messageproviders;
 564 }
 565
 566 /**
 567  * Remove all message providers for particular component and corresponding settings
 568  *
 569  * @param string $component A moodle component like 'moodle', 'mod_forum', 'block_quiz_results'
 570  * @return void
 571  */
 572 function message_provider_uninstall($component) {
 573     global $DB;
 574
 575     $transaction = $DB->start_delegated_transaction();
 576     $DB->delete_records('message_providers', array('component' => $component));
 577     $DB->delete_records_select('config_plugins', "plugin = 'message' AND ".$DB->sql_like('name', '?', false), array("%_provider_{$component}_%"));
 578     $DB->delete_records_select('user_preferences', $DB->sql_like('name', '?', false), array("message_provider_{$component}_%"));
 579     $transaction->allow_commit();
 580     // Purge all messaging settings from the caches. They are stored by plugin so we have to clear all message settings.
 581     cache_helper::invalidate_by_definition('core', 'config', array(), 'message');
 582 }
 583
 584 /**
 585  * Uninstall a message processor
 586  *
 587  * @param string $name A message processor name like 'email', 'jabber'
 588  */
 589 function message_processor_uninstall($name) {
 590     global $DB;
 591
 592     $transaction = $DB->start_delegated_transaction();
 593     $DB->delete_records('message_processors', array('name' => $name));
 594     $DB->delete_records_select('config_plugins', "plugin = ?", array("message_{$name}"));
 595     // delete permission preferences only, we do not care about loggedin/loggedoff
 596     // defaults, they will be removed on the next attempt to update the preferences
 597     $DB->delete_records_select('config_plugins', "plugin = 'message' AND ".$DB->sql_like('name', '?', false), array("{$name}_provider_%"));
 598     $transaction->allow_commit();
 599     // Purge all messaging settings from the caches. They are stored by plugin so we have to clear all message settings.
 600     cache_helper::invalidate_by_definition('core', 'config', array(), array('message', "message_{$name}"));
 601 }