From 14de10c4637a22516fedbc7fdb262ca6cf9734b5 Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Sun, 14 Oct 2018 19:15:30 +0800
Subject: [PATCH 1/7] MDL-63547 core_message: updated message_deleted event to
 support groups

---
 lib/classes/event/message_deleted.php | 64 ++++++++++++---------------
 lib/upgrade.txt                       |  3 ++
 message/classes/api.php               | 27 ++++-------
 message/tests/events_test.php         | 26 +++++------
 4 files changed, 51 insertions(+), 69 deletions(-)

diff --git a/lib/classes/event/message_deleted.php b/lib/classes/event/message_deleted.php
index b991853b309..ab38448b1db 100644
--- a/lib/classes/event/message_deleted.php
+++ b/lib/classes/event/message_deleted.php
@@ -33,8 +33,6 @@ defined('MOODLE_INTERNAL') || die();
  *      Extra information about event.
  *
  *      - int messageid: the id of the message.
- *      - int useridfrom: the id of the user who received the message.
- *      - int useridto: the id of the user who sent the message.
  * }
  *
  * @package    core
@@ -47,32 +45,22 @@ class message_deleted extends base {
     /**
      * Create event using ids.
      *
-     * @param int $userfromid the user who the message was from.
-     * @param int $usertoid the user who the message was sent to.
-     * @param int $userdeleted the user who deleted it.
+     * @param int $userid the user who the we are deleting the message for.
+     * @param int $userdeleting the user who deleted it (it's possible that an admin may delete a message on someones behalf)
      * @param int $messageid the id of the message that was deleted.
-     * @param int $muaid The id in the message_user_actions table
+     * @param int $muaid The id in the message_user_actions table.
      * @return message_deleted
      */
-    public static function create_from_ids($userfromid, $usertoid, $userdeleted, $messageid, $muaid) {
-        // Check who was deleting the message.
-        if ($userdeleted == $userfromid) {
-            $relateduserid = $usertoid;
-        } else {
-            $relateduserid = $userfromid;
-        }
-
+    public static function create_from_ids(int $userid, int $userdeleting, int $messageid, int $muaid) : message_deleted {
         // We set the userid to the user who deleted the message, nothing to do
         // with whether or not they sent or received the message.
         $event = self::create(array(
             'objectid' => $muaid,
-            'userid' => $userdeleted,
+            'userid' => $userdeleting,
             'context' => \context_system::instance(),
-            'relateduserid' => $relateduserid,
+            'relateduserid' => $userid,
             'other' => array(
                 'messageid' => $messageid,
-                'useridfrom' => $userfromid,
-                'useridto' => $usertoid
             )
         ));
 
@@ -103,14 +91,28 @@ class message_deleted extends base {
      * @return string
      */
     public function get_description() {
-        // Check if the person who deleted the message received or sent it.
-        if ($this->userid == $this->other['useridto']) {
-            $str = 'from';
-        } else {
-            $str = 'to';
+        // This is for BC when the event used to take this value into account before group conversations.
+        // We still want the same message to display for older events.
+        if (isset($this->other['useridto'])) {
+            // Check if the person who deleted the message received or sent it.
+            if ($this->userid == $this->other['useridto']) {
+                $str = 'from';
+            } else {
+                $str = 'to';
+            }
+
+            return "The user with id '$this->userid' deleted a message sent $str the user with id '$this->relateduserid'.";
         }
 
-        return "The user with id '$this->userid' deleted a message sent $str the user with id '$this->relateduserid'.";
+        $messageid = $this->other['messageid'];
+
+        // Check if the user deleting the message was not the actual user we are deleting for.
+        $str = "The user with id '$this->userid' deleted a message with id '$messageid'";
+        if ($this->userid != $this->relateduserid) {
+            $str .= " for the user with id '$this->relateduserid'";
+        }
+
+        return $str;
     }
 
     /**
@@ -129,14 +131,6 @@ class message_deleted extends base {
         if (!isset($this->other['messageid'])) {
             throw new \coding_exception('The \'messageid\' value must be set in other.');
         }
-
-        if (!isset($this->other['useridfrom'])) {
-            throw new \coding_exception('The \'useridfrom\' value must be set in other.');
-        }
-
-        if (!isset($this->other['useridto'])) {
-            throw new \coding_exception('The \'useridto\' value must be set in other.');
-        }
     }
 
     public static function get_objectid_mapping() {
@@ -145,9 +139,9 @@ class message_deleted extends base {
 
     public static function get_other_mapping() {
         // Messages are not backed up, so no need to map them on restore.
-        $othermapped = array();
-        $othermapped['useridfrom'] = array('db' => 'user', 'restore' => base::NOT_MAPPED);
-        $othermapped['useridto'] = array('db' => 'user', 'restore' => base::NOT_MAPPED);
+        $othermapped = [];
+        $othermapped['messageid'] = ['db' => 'messages', 'restore' => base::NOT_MAPPED];
+
         return $othermapped;
     }
 }
diff --git a/lib/upgrade.txt b/lib/upgrade.txt
index 288ed76e1bc..6561f6525cd 100644
--- a/lib/upgrade.txt
+++ b/lib/upgrade.txt
@@ -135,6 +135,9 @@ the groupid field.
   - message_contact_unblocked
   The reason for this is because you can now block/unblock users without them necessarily being a contact. These events
   have been replaced with message_user_blocked and message_user_unblocked respectively.
+* The event message_deleted has been changed, it no longer records the value of the 'useridto' due to
+  the introduction of group messaging. Please, if you have any observers or are triggering this event
+  in your code you will have to make some changes!
 
 === 3.5 ===
 
diff --git a/message/classes/api.php b/message/classes/api.php
index 8bc93a74288..d8b07950b4e 100644
--- a/message/classes/api.php
+++ b/message/classes/api.php
@@ -686,13 +686,8 @@ class api {
             $mua->timecreated = time();
             $mua->id = $DB->insert_record('message_user_actions', $mua);
 
-            if ($message->useridfrom == $userid) {
-                $useridto = $otheruserid;
-            } else {
-                $useridto = $userid;
-            }
-            \core\event\message_deleted::create_from_ids($message->useridfrom, $useridto,
-                $USER->id, $message->id, $mua->id)->trigger();
+            \core\event\message_deleted::create_from_ids($userid, $USER->id,
+                $message->id, $mua->id)->trigger();
         }
 
         return true;
@@ -1243,17 +1238,11 @@ class api {
      * @return bool
      */
     public static function delete_message($userid, $messageid) {
-        global $DB;
+        global $DB, $USER;
 
-        $sql = "SELECT m.id, m.useridfrom, mcm.userid as useridto
-                  FROM {messages} m
-            INNER JOIN {message_conversations} mc
-                    ON m.conversationid = mc.id
-            INNER JOIN {message_conversation_members} mcm
-                    ON mcm.conversationid = mc.id
-                 WHERE mcm.userid != m.useridfrom
-                   AND m.id = ?";
-        $message = $DB->get_record_sql($sql, [$messageid], MUST_EXIST);
+        if (!$DB->record_exists('messages', ['id' => $messageid])) {
+            return false;
+        }
 
         // Check if the user has already deleted this message.
         if (!$DB->record_exists('message_user_actions', ['userid' => $userid,
@@ -1266,8 +1255,8 @@ class api {
             $mua->id = $DB->insert_record('message_user_actions', $mua);
 
             // Trigger event for deleting a message.
-            \core\event\message_deleted::create_from_ids($message->useridfrom, $message->useridto,
-                $userid, $message->id, $mua->id)->trigger();
+            \core\event\message_deleted::create_from_ids($userid, $USER->id,
+                $messageid, $mua->id)->trigger();
 
             return true;
         }
diff --git a/message/tests/events_test.php b/message/tests/events_test.php
index 25660ce5054..973eddf2a43 100644
--- a/message/tests/events_test.php
+++ b/message/tests/events_test.php
@@ -274,7 +274,9 @@ class core_message_events_testcase extends core_message_messagelib_testcase {
      * Test the message deleted event.
      */
     public function test_message_deleted() {
-        global $DB;
+        global $DB, $USER;
+
+        $this->setAdminUser();
 
         // Create users to send messages between.
         $user1 = $this->getDataGenerator()->create_user();
@@ -294,12 +296,12 @@ class core_message_events_testcase extends core_message_messagelib_testcase {
 
         // Check that the event data is valid.
         $this->assertInstanceOf('\core\event\message_deleted', $event);
-        $this->assertEquals($user1->id, $event->userid); // The user who deleted it.
-        $this->assertEquals($user2->id, $event->relateduserid);
+        $this->assertEquals($USER->id, $event->userid); // The user who deleted it.
+        $this->assertEquals($user1->id, $event->relateduserid);
         $this->assertEquals($mua->id, $event->objectid);
         $this->assertEquals($messageid, $event->other['messageid']);
-        $this->assertEquals($user1->id, $event->other['useridfrom']);
-        $this->assertEquals($user2->id, $event->other['useridto']);
+
+        $this->setUser($user1);
 
         // Create a read message.
         $messageid = $this->send_fake_message($user1, $user2);
@@ -318,12 +320,10 @@ class core_message_events_testcase extends core_message_messagelib_testcase {
 
         // Check that the event data is valid.
         $this->assertInstanceOf('\core\event\message_deleted', $event);
-        $this->assertEquals($user2->id, $event->userid);
-        $this->assertEquals($user1->id, $event->relateduserid);
+        $this->assertEquals($user1->id, $event->userid);
+        $this->assertEquals($user2->id, $event->relateduserid);
         $this->assertEquals($mua->id, $event->objectid);
         $this->assertEquals($messageid, $event->other['messageid']);
-        $this->assertEquals($user1->id, $event->other['useridfrom']);
-        $this->assertEquals($user2->id, $event->other['useridto']);
     }
 
     /**
@@ -336,7 +336,7 @@ class core_message_events_testcase extends core_message_messagelib_testcase {
         $user1 = self::getDataGenerator()->create_user();
         $user2 = self::getDataGenerator()->create_user();
 
-        // The person doing the search.
+        // The person doing the deletion.
         $this->setUser($user1);
 
         // Send some messages back and forth.
@@ -383,18 +383,14 @@ class core_message_events_testcase extends core_message_messagelib_testcase {
         // Check that the event data is valid.
         $i = 1;
         foreach ($events as $event) {
-            $useridfromid = ($i % 2 == 0) ? $user2->id : $user1->id;
-            $useridtoid = ($i % 2 == 0) ? $user1->id : $user2->id;
             $messageid = $messages[$i - 1];
 
             $this->assertInstanceOf('\core\event\message_deleted', $event);
 
             $this->assertEquals($muatest[$messageid]->id, $event->objectid);
             $this->assertEquals($user1->id, $event->userid);
-            $this->assertEquals($user2->id, $event->relateduserid);
+            $this->assertEquals($user1->id, $event->relateduserid);
             $this->assertEquals($messageid, $event->other['messageid']);
-            $this->assertEquals($useridfromid, $event->other['useridfrom']);
-            $this->assertEquals($useridtoid, $event->other['useridto']);
 
             $i++;
         }

From 08cb8a34f999830c9722abd928f4c72a4f8b91fd Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Sun, 14 Oct 2018 19:48:13 +0800
Subject: [PATCH 2/7] MDL-63547 core_message: updated api::can_delete_message

---
 message/classes/api.php            | 45 +++++++++++++++++-------------
 message/tests/api_test.php         | 25 +++++++++++++++++
 message/tests/externallib_test.php |  2 +-
 3 files changed, 51 insertions(+), 21 deletions(-)

diff --git a/message/classes/api.php b/message/classes/api.php
index d8b07950b4e..4320e25ea89 100644
--- a/message/classes/api.php
+++ b/message/classes/api.php
@@ -1197,30 +1197,20 @@ class api {
     public static function can_delete_message($userid, $messageid) {
         global $DB, $USER;
 
-        $sql = "SELECT m.id, m.useridfrom, mcm.userid as useridto
-                  FROM {messages} m
-            INNER JOIN {message_conversations} mc
-                    ON m.conversationid = mc.id
-            INNER JOIN {message_conversation_members} mcm
-                    ON mcm.conversationid = mc.id
-                 WHERE mcm.userid != m.useridfrom
-                   AND m.id = ?";
-        $message = $DB->get_record_sql($sql, [$messageid], MUST_EXIST);
+        $systemcontext = \context_system::instance();
 
-        if ($message->useridfrom == $userid) {
-            $userdeleting = 'useridfrom';
-        } else if ($message->useridto == $userid) {
-            $userdeleting = 'useridto';
-        } else {
+        $conversationid = $DB->get_field('messages', 'conversationid', ['id' => $messageid], MUST_EXIST);
+
+        if (has_capability('moodle/site:deleteanymessage', $systemcontext)) {
+            return true;
+        }
+
+        if (!self::is_user_in_conversation($userid, $conversationid)) {
             return false;
         }
 
-        $systemcontext = \context_system::instance();
-
-        // Let's check if the user is allowed to delete this message.
-        if (has_capability('moodle/site:deleteanymessage', $systemcontext) ||
-            ((has_capability('moodle/site:deleteownmessage', $systemcontext) &&
-                $USER->id == $message->$userdeleting))) {
+        if (has_capability('moodle/site:deleteownmessage', $systemcontext) &&
+                $USER->id == $userid) {
             return true;
         }
 
@@ -1601,4 +1591,19 @@ class api {
                     OR (mcr.userid = ? AND mcr.requesteduserid = ?)";
         return $DB->record_exists_sql($sql, [$userid, $requesteduserid, $requesteduserid, $userid]);
     }
+
+    /**
+     * Checks if a user is already in a conversation.
+     *
+     * @param int $userid The id of the user we want to check if they are in a group
+     * @param int $conversationid The id of the conversation
+     * @return bool Returns true if a contact request exists, false otherwise
+     */
+    public static function is_user_in_conversation(int $userid, int $conversationid) : bool {
+        global $DB;
+
+        return $DB->record_exists('message_conversation_members', ['conversationid' => $conversationid,
+            'userid' => $userid]);
+
+    }
 }
diff --git a/message/tests/api_test.php b/message/tests/api_test.php
index 0278d679352..f9f1cfc15c2 100644
--- a/message/tests/api_test.php
+++ b/message/tests/api_test.php
@@ -2226,6 +2226,31 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         $this->assertTrue(\core_message\api::does_contact_request_exist($user2->id, $user1->id));
     }
 
+    /**
+     * Test the user in conversation check.
+     */
+    public function test_is_user_in_conversation() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        $conversationid = \core_message\api::create_conversation_between_users([$user1->id, $user2->id]);
+
+        $this->assertTrue(\core_message\api::is_user_in_conversation($user1->id, $conversationid));
+    }
+
+    /**
+     * Test the user in conversation check when they are not.
+     */
+    public function test_is_user_in_conversation_when_not() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        $conversationid = \core_message\api::create_conversation_between_users([$user1->id, $user2->id]);
+
+        $this->assertFalse(\core_message\api::is_user_in_conversation($user3->id, $conversationid));
+    }
+
     /**
      * Comparison function for sorting contacts.
      *
diff --git a/message/tests/externallib_test.php b/message/tests/externallib_test.php
index 784ad149ee2..6b503e5c7de 100644
--- a/message/tests/externallib_test.php
+++ b/message/tests/externallib_test.php
@@ -1648,7 +1648,7 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
             $result = core_message_external::delete_message(-1, $user1->id);
             $this->fail('Exception expected due invalid messageid.');
         } catch (dml_missing_record_exception $e) {
-            $this->assertEquals('invalidrecordunknown', $e->errorcode);
+            $this->assertEquals('invalidrecord', $e->errorcode);
         }
 
         // Invalid user.

From 263ad98436c27eb36406667159a3c482117f86e2 Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Sun, 14 Oct 2018 14:03:03 +0800
Subject: [PATCH 3/7] MDL-63547 core_message: deprecated
 api::delete_conversation()

---
 message/classes/api.php       | 23 ++++++++++++++--
 message/externallib.php       |  5 +++-
 message/tests/api_test.php    | 52 +++++++++++++++++++++++++++++++++++
 message/tests/events_test.php |  1 +
 message/upgrade.txt           |  1 +
 5 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/message/classes/api.php b/message/classes/api.php
index 4320e25ea89..f4e260e231a 100644
--- a/message/classes/api.php
+++ b/message/classes/api.php
@@ -650,13 +650,15 @@ class api {
      *
      * This function does not verify any permissions.
      *
+     * @deprecated since 3.6
      * @param int $userid The user id of who we want to delete the messages for (this may be done by the admin
      *  but will still seem as if it was by the user)
      * @param int $otheruserid The id of the other user in the conversation
      * @return bool
      */
     public static function delete_conversation($userid, $otheruserid) {
-        global $DB, $USER;
+        debugging('\core_message\api::delete_conversation() is deprecated, please use ' .
+            '\core_message\api::delete_conversation_by_id() instead.', DEBUG_DEVELOPER);
 
         $conversationid = self::get_conversation_between_users([$userid, $otheruserid]);
 
@@ -665,6 +667,23 @@ class api {
             return true;
         }
 
+        self::delete_conversation_by_id($userid, $conversationid);
+
+        return true;
+    }
+
+    /**
+     * Deletes a conversation for a specified user.
+     *
+     * This function does not verify any permissions.
+     *
+     * @param int $userid The user id of who we want to delete the messages for (this may be done by the admin
+     *  but will still seem as if it was by the user)
+     * @param int $conversationid The id of the other user in the conversation
+     */
+    public static function delete_conversation_by_id(int $userid, int $conversationid) {
+        global $DB, $USER;
+
         // Get all messages belonging to this conversation that have not already been deleted by this user.
         $sql = "SELECT m.*
                  FROM {messages} m
@@ -689,8 +708,6 @@ class api {
             \core\event\message_deleted::create_from_ids($userid, $USER->id,
                 $message->id, $mua->id)->trigger();
         }
-
-        return true;
     }
 
     /**
diff --git a/message/externallib.php b/message/externallib.php
index f678c2f2732..30f056beb89 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -2588,7 +2588,10 @@ class core_message_external extends external_api {
         core_user::require_active_user($user);
 
         if (\core_message\api::can_delete_conversation($user->id)) {
-            $status = \core_message\api::delete_conversation($user->id, $otheruserid);
+            if ($conversationid = \core_message\api::get_conversation_between_users([$userid, $otheruserid])) {
+                \core_message\api::delete_conversation_by_id($user->id, $conversationid);
+            }
+            $status = true;
         } else {
             throw new moodle_exception('You do not have permission to delete messages');
         }
diff --git a/message/tests/api_test.php b/message/tests/api_test.php
index f9f1cfc15c2..ed4a27266ae 100644
--- a/message/tests/api_test.php
+++ b/message/tests/api_test.php
@@ -1181,6 +1181,58 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
 
         // Delete the conversation as user 1.
         \core_message\api::delete_conversation($user1->id, $user2->id);
+        $this->assertDebuggingCalled();
+
+        $muas = $DB->get_records('message_user_actions', array(), 'timecreated ASC');
+        $this->assertCount(4, $muas);
+        // Sort by id.
+        ksort($muas);
+
+        $mua1 = array_shift($muas);
+        $mua2 = array_shift($muas);
+        $mua3 = array_shift($muas);
+        $mua4 = array_shift($muas);
+
+        $this->assertEquals($user1->id, $mua1->userid);
+        $this->assertEquals($m1id, $mua1->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua1->action);
+
+        $this->assertEquals($user1->id, $mua2->userid);
+        $this->assertEquals($m2id, $mua2->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua2->action);
+
+        $this->assertEquals($user1->id, $mua3->userid);
+        $this->assertEquals($m3id, $mua3->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua3->action);
+
+        $this->assertEquals($user1->id, $mua4->userid);
+        $this->assertEquals($m4id, $mua4->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua4->action);
+    }
+
+    /**
+     * Tests deleting a conversation by conversation id.
+     */
+    public function test_delete_conversation_by_id() {
+        global $DB;
+
+        // Create some users.
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        // The person doing the search.
+        $this->setUser($user1);
+
+        // Send some messages back and forth.
+        $time = 1;
+        $m1id = $this->send_fake_message($user1, $user2, 'Yo!', 0, $time + 1);
+        $m2id = $this->send_fake_message($user2, $user1, 'Sup mang?', 0, $time + 2);
+        $m3id = $this->send_fake_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 3);
+        $m4id = $this->send_fake_message($user2, $user1, 'Word.', 0, $time + 4);
+
+        // Delete the conversation as user 1.
+        $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
+        \core_message\api::delete_conversation_by_id($user1->id, $conversationid);
 
         $muas = $DB->get_records('message_user_actions', array(), 'timecreated ASC');
         $this->assertCount(4, $muas);
diff --git a/message/tests/events_test.php b/message/tests/events_test.php
index 973eddf2a43..714461b9fce 100644
--- a/message/tests/events_test.php
+++ b/message/tests/events_test.php
@@ -364,6 +364,7 @@ class core_message_events_testcase extends core_message_messagelib_testcase {
         // Trigger and capture the event.
         $sink = $this->redirectEvents();
         \core_message\api::delete_conversation($user1->id, $user2->id);
+        $this->assertDebuggingCalled();
         $events = $sink->get_events();
 
         // Get the user actions for the messages deleted by that user.
diff --git a/message/upgrade.txt b/message/upgrade.txt
index 2ada6522aee..aad4d002a39 100644
--- a/message/upgrade.txt
+++ b/message/upgrade.txt
@@ -28,6 +28,7 @@ information provided here is intended especially for developers.
   Please see their declaration in lib/deprecatedlib.php to view their alternatives (if applicable).
 * The following methods have been deprecated and should not be used any more:
   - \core_message\api::is_user_blocked()
+  - \core_message\api::delete_conversation()
 * The following web services have been deprecated. Please do not call these any more.
   - core_message_external::block_contacts, please use core_message_external::block_user instead.
   - core_message_external::unblock_contacts, please use core_message_external::unblock_user instead.

From 15663b0bec15b0bbd538a16bc6c9ba325960a394 Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Sun, 14 Oct 2018 21:00:01 +0800
Subject: [PATCH 4/7] MDL-63547 core_message: can_delete_conversation expects a
 conversationid

---
 message/classes/api.php            | 23 ++++++++++++++++++-----
 message/externallib.php            | 10 ++++++----
 message/tests/api_test.php         | 15 ++++++++++++---
 message/tests/externallib_test.php |  7 +++++++
 message/upgrade.txt                |  2 ++
 5 files changed, 45 insertions(+), 12 deletions(-)

diff --git a/message/classes/api.php b/message/classes/api.php
index f4e260e231a..092f47c2990 100644
--- a/message/classes/api.php
+++ b/message/classes/api.php
@@ -628,17 +628,30 @@ class api {
      *
      * @param int $userid The user id of who we want to delete the messages for (this may be done by the admin
      *  but will still seem as if it was by the user)
+     * @param int $conversationid The id of the conversation
      * @return bool Returns true if a user can delete the conversation, false otherwise.
      */
-    public static function can_delete_conversation($userid) {
+    public static function can_delete_conversation(int $userid, int $conversationid = null) : bool {
         global $USER;
 
+        if (is_null($conversationid)) {
+            debugging('\core_message\api::can_delete_conversation() now expects a \'conversationid\' to be passed.',
+                DEBUG_DEVELOPER);
+            return false;
+        }
+
         $systemcontext = \context_system::instance();
 
-        // Let's check if the user is allowed to delete this conversation.
-        if (has_capability('moodle/site:deleteanymessage', $systemcontext) ||
-            ((has_capability('moodle/site:deleteownmessage', $systemcontext) &&
-                $USER->id == $userid))) {
+        if (has_capability('moodle/site:deleteanymessage', $systemcontext)) {
+            return true;
+        }
+
+        if (!self::is_user_in_conversation($userid, $conversationid)) {
+            return false;
+        }
+
+        if (has_capability('moodle/site:deleteownmessage', $systemcontext) &&
+                $USER->id == $userid) {
             return true;
         }
 
diff --git a/message/externallib.php b/message/externallib.php
index 30f056beb89..32185bab3c1 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -2587,10 +2587,12 @@ class core_message_external extends external_api {
         $user = core_user::get_user($params['userid'], '*', MUST_EXIST);
         core_user::require_active_user($user);
 
-        if (\core_message\api::can_delete_conversation($user->id)) {
-            if ($conversationid = \core_message\api::get_conversation_between_users([$userid, $otheruserid])) {
-                \core_message\api::delete_conversation_by_id($user->id, $conversationid);
-            }
+        if (!$conversationid = \core_message\api::get_conversation_between_users([$userid, $otheruserid])) {
+            return [];
+        }
+
+        if (\core_message\api::can_delete_conversation($user->id, $conversationid)) {
+            \core_message\api::delete_conversation_by_id($user->id, $conversationid);
             $status = true;
         } else {
             throw new moodle_exception('You do not have permission to delete messages');
diff --git a/message/tests/api_test.php b/message/tests/api_test.php
index ed4a27266ae..f3253e6eb83 100644
--- a/message/tests/api_test.php
+++ b/message/tests/api_test.php
@@ -1146,17 +1146,26 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         $user1 = self::getDataGenerator()->create_user();
         $user2 = self::getDataGenerator()->create_user();
 
+        // Send some messages back and forth.
+        $time = 1;
+        $this->send_fake_message($user1, $user2, 'Yo!', 0, $time + 1);
+        $this->send_fake_message($user2, $user1, 'Sup mang?', 0, $time + 2);
+        $this->send_fake_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 3);
+        $this->send_fake_message($user2, $user1, 'Word.', 0, $time + 4);
+
+        $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
+
         // The admin can do anything.
-        $this->assertTrue(\core_message\api::can_delete_conversation($user1->id));
+        $this->assertTrue(\core_message\api::can_delete_conversation($user1->id, $conversationid));
 
         // Set as the user 1.
         $this->setUser($user1);
 
         // They can delete their own messages.
-        $this->assertTrue(\core_message\api::can_delete_conversation($user1->id));
+        $this->assertTrue(\core_message\api::can_delete_conversation($user1->id, $conversationid));
 
         // They can't delete someone elses.
-        $this->assertFalse(\core_message\api::can_delete_conversation($user2->id));
+        $this->assertFalse(\core_message\api::can_delete_conversation($user2->id, $conversationid));
     }
 
     /**
diff --git a/message/tests/externallib_test.php b/message/tests/externallib_test.php
index 6b503e5c7de..584f15685ca 100644
--- a/message/tests/externallib_test.php
+++ b/message/tests/externallib_test.php
@@ -3445,6 +3445,13 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
         $user2 = self::getDataGenerator()->create_user();
         $user3 = self::getDataGenerator()->create_user();
 
+        // Send some messages back and forth.
+        $time = time();
+        $this->send_message($user1, $user2, 'Yo!', 0, $time);
+        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
+        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
+        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);
+
         // The person wanting to delete the conversation.
         $this->setUser($user3);
 
diff --git a/message/upgrade.txt b/message/upgrade.txt
index aad4d002a39..c95b7348bfc 100644
--- a/message/upgrade.txt
+++ b/message/upgrade.txt
@@ -29,6 +29,8 @@ information provided here is intended especially for developers.
 * The following methods have been deprecated and should not be used any more:
   - \core_message\api::is_user_blocked()
   - \core_message\api::delete_conversation()
+* The method \core_message\api::can_delete_conversation() now expects a 'conversationid' to be passed
+  as the second parameter.
 * The following web services have been deprecated. Please do not call these any more.
   - core_message_external::block_contacts, please use core_message_external::block_user instead.
   - core_message_external::unblock_contacts, please use core_message_external::unblock_user instead.

From fa024820f28ff38f3c0fbcaf1f173eec5e845a9e Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Mon, 15 Oct 2018 17:42:15 +0800
Subject: [PATCH 5/7] MDL-63547 core_message: deprecate delete_conversation web
 service

---
 lib/db/services.php     |  3 ++-
 message/externallib.php | 13 ++++++++++++-
 message/upgrade.txt     |  7 ++++---
 3 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/lib/db/services.php b/lib/db/services.php
index 10bd788f3bd..36bdc0794f4 100644
--- a/lib/db/services.php
+++ b/lib/db/services.php
@@ -917,7 +917,8 @@ $functions = array(
         'classname' => 'core_message_external',
         'methodname' => 'delete_conversation',
         'classpath' => 'message/externallib.php',
-        'description' => 'Deletes a conversation.',
+        'description' => '** DEPRECATED ** Please do not call this function any more.
+                          Deletes a conversation.',
         'type' => 'write',
         'capabilities' => 'moodle/site:deleteownmessage',
         'ajax' => true,
diff --git a/message/externallib.php b/message/externallib.php
index 32185bab3c1..e5073b5296e 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -2541,6 +2541,7 @@ class core_message_external extends external_api {
     /**
      * Returns description of method parameters.
      *
+     * @deprecated since 3.6
      * @return external_function_parameters
      * @since 3.2
      */
@@ -2556,6 +2557,7 @@ class core_message_external extends external_api {
     /**
      * Deletes a conversation.
      *
+     * @deprecated since 3.6
      * @param int $userid The user id of who we want to delete the conversation for
      * @param int $otheruserid The user id of the other user in the conversation
      * @return array
@@ -2609,6 +2611,7 @@ class core_message_external extends external_api {
     /**
      * Returns description of method result value.
      *
+     * @deprecated since 3.6
      * @return external_description
      * @since 3.2
      */
@@ -2621,6 +2624,15 @@ class core_message_external extends external_api {
         );
     }
 
+    /**
+     * Marking the method as deprecated.
+     *
+     * @return bool
+     */
+    public static function delete_conversation_is_deprecated() {
+        return true;
+    }
+
     /**
      * Returns description of method parameters
      *
@@ -3017,7 +3029,6 @@ class core_message_external extends external_api {
         );
     }
 
-
     /**
      * Returns description of method parameters
      *
diff --git a/message/upgrade.txt b/message/upgrade.txt
index c95b7348bfc..969e3b7bfda 100644
--- a/message/upgrade.txt
+++ b/message/upgrade.txt
@@ -32,9 +32,10 @@ information provided here is intended especially for developers.
 * The method \core_message\api::can_delete_conversation() now expects a 'conversationid' to be passed
   as the second parameter.
 * The following web services have been deprecated. Please do not call these any more.
-  - core_message_external::block_contacts, please use core_message_external::block_user instead.
-  - core_message_external::unblock_contacts, please use core_message_external::unblock_user instead.
-  - core_message_external::create_contacts, please use core_message_external::create_contact_request instead.
+  - core_message_external::block_contacts(), please use core_message_external::block_user() instead.
+  - core_message_external::unblock_contacts(), please use core_message_external::unblock_user() instead.
+  - core_message_external::create_contacts(), please use core_message_external::create_contact_request() instead.
+  - core_message_external::delete_conversation(), please use core_message_external::delete_conversation_by_id() instead.
 
 === 3.5 ===
 

From 26f39c88618cecca0107235b27bb74d38bc3fe10 Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Mon, 15 Oct 2018 17:43:21 +0800
Subject: [PATCH 6/7] MDL-63547 core_message: added delete_conversation_by_id
 web service

---
 lib/db/services.php                |  10 ++
 message/externallib.php            |  65 +++++++++++
 message/tests/externallib_test.php | 167 +++++++++++++++++++++++++++++
 version.php                        |   2 +-
 4 files changed, 243 insertions(+), 1 deletion(-)

diff --git a/lib/db/services.php b/lib/db/services.php
index 36bdc0794f4..033de846610 100644
--- a/lib/db/services.php
+++ b/lib/db/services.php
@@ -924,6 +924,16 @@ $functions = array(
         'ajax' => true,
         'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
     ),
+    'core_message_delete_conversation_by_id' => array(
+        'classname' => 'core_message_external',
+        'methodname' => 'delete_conversation_by_id',
+        'classpath' => 'message/externallib.php',
+        'description' => 'Deletes a conversation.',
+        'type' => 'write',
+        'capabilities' => 'moodle/site:deleteownmessage',
+        'ajax' => true,
+        'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
+    ),
     'core_message_delete_message' => array(
         'classname' => 'core_message_external',
         'methodname' => 'delete_message',
diff --git a/message/externallib.php b/message/externallib.php
index e5073b5296e..a8d0f0c167a 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -2633,6 +2633,71 @@ class core_message_external extends external_api {
         return true;
     }
 
+    /**
+     * Returns description of method parameters.
+     *
+     * @return external_function_parameters
+     * @since 3.6
+     */
+    public static function delete_conversation_by_id_parameters() {
+        return new external_function_parameters(
+            array(
+                'userid' => new external_value(PARAM_INT, 'The user id of who we want to delete the conversation for'),
+                'conversationid' => new external_value(PARAM_INT, 'The id of the conversation'),
+            )
+        );
+    }
+
+    /**
+     * Deletes a conversation.
+     *
+     * @param int $userid The user id of who we want to delete the conversation for
+     * @param int $conversationid The id of the conversation
+     * @return array
+     * @throws moodle_exception
+     * @since 3.6
+     */
+    public static function delete_conversation_by_id($userid, $conversationid) {
+        global $CFG;
+
+        // Check if private messaging between users is allowed.
+        if (empty($CFG->messaging)) {
+            throw new moodle_exception('disabled', 'message');
+        }
+
+        // Validate params.
+        $params = [
+            'userid' => $userid,
+            'conversationid' => $conversationid,
+        ];
+        $params = self::validate_parameters(self::delete_conversation_by_id_parameters(), $params);
+
+        // Validate context.
+        $context = context_system::instance();
+        self::validate_context($context);
+
+        $user = core_user::get_user($params['userid'], '*', MUST_EXIST);
+        core_user::require_active_user($user);
+
+        if (\core_message\api::can_delete_conversation($user->id, $conversationid)) {
+            \core_message\api::delete_conversation_by_id($user->id, $conversationid);
+        } else {
+            throw new moodle_exception("You do not have permission to delete the conversation '$conversationid'");
+        }
+
+        return [];
+    }
+
+    /**
+     * Returns description of method result value.
+     *
+     * @return external_description
+     * @since 3.6
+     */
+    public static function delete_conversation_by_id_returns() {
+        return new external_warnings();
+    }
+
     /**
      * Returns description of method parameters
      *
diff --git a/message/tests/externallib_test.php b/message/tests/externallib_test.php
index 584f15685ca..92dae3f1948 100644
--- a/message/tests/externallib_test.php
+++ b/message/tests/externallib_test.php
@@ -3483,6 +3483,173 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
         core_message_external::delete_conversation($user1->id, $user2->id);
     }
 
+    /**
+     * Test deleting conversation.
+     */
+    public function test_delete_conversation_by_id() {
+        global $DB;
+
+        $this->resetAfterTest(true);
+
+        // Create some users.
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        // The person wanting to delete the conversation.
+        $this->setUser($user1);
+
+        // Send some messages back and forth.
+        $time = time();
+        $m1id = $this->send_message($user1, $user2, 'Yo!', 0, $time);
+        $m2id = $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
+        $m3id = $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
+        $m4id = $this->send_message($user2, $user1, 'Word.', 0, $time + 3);
+
+        $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
+
+        // Delete the conversation.
+        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+
+        $muas = $DB->get_records('message_user_actions', array(), 'timecreated ASC');
+        $this->assertCount(4, $muas);
+        // Sort by id.
+        ksort($muas);
+
+        $mua1 = array_shift($muas);
+        $mua2 = array_shift($muas);
+        $mua3 = array_shift($muas);
+        $mua4 = array_shift($muas);
+
+        $this->assertEquals($user1->id, $mua1->userid);
+        $this->assertEquals($m1id, $mua1->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua1->action);
+
+        $this->assertEquals($user1->id, $mua2->userid);
+        $this->assertEquals($m2id, $mua2->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua2->action);
+
+        $this->assertEquals($user1->id, $mua3->userid);
+        $this->assertEquals($m3id, $mua3->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua3->action);
+
+        $this->assertEquals($user1->id, $mua4->userid);
+        $this->assertEquals($m4id, $mua4->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua4->action);
+    }
+
+    /**
+     * Test deleting conversation as other user.
+     */
+    public function test_delete_conversation_by_id_as_other_user() {
+        global $DB;
+
+        $this->resetAfterTest(true);
+
+        $this->setAdminUser();
+
+        // Create some users.
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        // Send some messages back and forth.
+        $time = time();
+        $m1id = $this->send_message($user1, $user2, 'Yo!', 0, $time);
+        $m2id = $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
+        $m3id = $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
+        $m4id = $this->send_message($user2, $user1, 'Word.', 0, $time + 3);
+
+        $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
+
+        // Delete the conversation.
+        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+
+        $muas = $DB->get_records('message_user_actions', array(), 'timecreated ASC');
+        $this->assertCount(4, $muas);
+        // Sort by id.
+        ksort($muas);
+
+        $mua1 = array_shift($muas);
+        $mua2 = array_shift($muas);
+        $mua3 = array_shift($muas);
+        $mua4 = array_shift($muas);
+
+        $this->assertEquals($user1->id, $mua1->userid);
+        $this->assertEquals($m1id, $mua1->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua1->action);
+
+        $this->assertEquals($user1->id, $mua2->userid);
+        $this->assertEquals($m2id, $mua2->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua2->action);
+
+        $this->assertEquals($user1->id, $mua3->userid);
+        $this->assertEquals($m3id, $mua3->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua3->action);
+
+        $this->assertEquals($user1->id, $mua4->userid);
+        $this->assertEquals($m4id, $mua4->messageid);
+        $this->assertEquals(\core_message\api::MESSAGE_ACTION_DELETED, $mua4->action);
+    }
+
+    /**
+     * Test deleting conversation as other user without proper capability.
+     */
+    public function test_delete_conversation_by_id_as_other_user_without_cap() {
+        $this->resetAfterTest(true);
+
+        // Create some users.
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        // Send some messages back and forth.
+        $time = time();
+        $this->send_message($user1, $user2, 'Yo!', 0, $time);
+        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
+        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
+        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);
+
+        $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
+
+        // The person wanting to delete the conversation.
+        $this->setUser($user3);
+
+        // Ensure an exception is thrown.
+        $this->expectException('moodle_exception');
+        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+    }
+
+    /**
+     * Test deleting conversation with messaging disabled.
+     */
+    public function test_delete_conversation_by_id_messaging_disabled() {
+        global $CFG;
+
+        $this->resetAfterTest(true);
+
+        // Create some users.
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        // Send some messages back and forth.
+        $time = time();
+        $this->send_message($user1, $user2, 'Yo!', 0, $time);
+        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
+        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
+        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);
+
+        $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
+
+        // The person wanting to delete the conversation.
+        $this->setUser($user1);
+
+        // Disable messaging.
+        $CFG->messaging = 0;
+
+        // Ensure an exception is thrown.
+        $this->expectException('moodle_exception');
+        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+    }
+
     /**
      * Test get message processor.
      */
diff --git a/version.php b/version.php
index 7f3abd4d453..4627b7a75af 100644
--- a/version.php
+++ b/version.php
@@ -29,7 +29,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$version  = 2018101100.00;              // YYYYMMDD      = weekly release date of this DEV branch.
+$version  = 2018101100.01;              // YYYYMMDD      = weekly release date of this DEV branch.
                                         //         RR    = release increments - 00 in DEV branches.
                                         //           .XX = incremental changes.
 

From 60b67bbcf7c3d4a889693f94fe46168065de6966 Mon Sep 17 00:00:00 2001
From: Mark Nelson <markn@moodle.com>
Date: Mon, 15 Oct 2018 12:20:23 +0800
Subject: [PATCH 7/7] MDL-63547 core_message: web service can delete multiple
 conversations

---
 lib/db/services.php                |  6 +++---
 message/externallib.php            | 27 ++++++++++++++++-----------
 message/tests/externallib_test.php | 24 ++++++++++++------------
 message/upgrade.txt                |  2 +-
 4 files changed, 32 insertions(+), 27 deletions(-)

diff --git a/lib/db/services.php b/lib/db/services.php
index 033de846610..f187293dfdd 100644
--- a/lib/db/services.php
+++ b/lib/db/services.php
@@ -924,11 +924,11 @@ $functions = array(
         'ajax' => true,
         'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
     ),
-    'core_message_delete_conversation_by_id' => array(
+    'core_message_delete_conversations_by_id' => array(
         'classname' => 'core_message_external',
-        'methodname' => 'delete_conversation_by_id',
+        'methodname' => 'delete_conversations_by_id',
         'classpath' => 'message/externallib.php',
-        'description' => 'Deletes a conversation.',
+        'description' => 'Deletes a list of conversations.',
         'type' => 'write',
         'capabilities' => 'moodle/site:deleteownmessage',
         'ajax' => true,
diff --git a/message/externallib.php b/message/externallib.php
index a8d0f0c167a..dec1cd573a2 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -2639,11 +2639,14 @@ class core_message_external extends external_api {
      * @return external_function_parameters
      * @since 3.6
      */
-    public static function delete_conversation_by_id_parameters() {
+    public static function delete_conversations_by_id_parameters() {
         return new external_function_parameters(
             array(
                 'userid' => new external_value(PARAM_INT, 'The user id of who we want to delete the conversation for'),
-                'conversationid' => new external_value(PARAM_INT, 'The id of the conversation'),
+                'conversationids' => new external_multiple_structure(
+                    new external_value(PARAM_INT, 'The id of the conversation'),
+                    'List of conversation IDs'
+                ),
             )
         );
     }
@@ -2652,12 +2655,12 @@ class core_message_external extends external_api {
      * Deletes a conversation.
      *
      * @param int $userid The user id of who we want to delete the conversation for
-     * @param int $conversationid The id of the conversation
+     * @param int[] $conversationids The ids of the conversations
      * @return array
      * @throws moodle_exception
      * @since 3.6
      */
-    public static function delete_conversation_by_id($userid, $conversationid) {
+    public static function delete_conversations_by_id($userid, array $conversationids) {
         global $CFG;
 
         // Check if private messaging between users is allowed.
@@ -2668,9 +2671,9 @@ class core_message_external extends external_api {
         // Validate params.
         $params = [
             'userid' => $userid,
-            'conversationid' => $conversationid,
+            'conversationids' => $conversationids,
         ];
-        $params = self::validate_parameters(self::delete_conversation_by_id_parameters(), $params);
+        $params = self::validate_parameters(self::delete_conversations_by_id_parameters(), $params);
 
         // Validate context.
         $context = context_system::instance();
@@ -2679,10 +2682,12 @@ class core_message_external extends external_api {
         $user = core_user::get_user($params['userid'], '*', MUST_EXIST);
         core_user::require_active_user($user);
 
-        if (\core_message\api::can_delete_conversation($user->id, $conversationid)) {
-            \core_message\api::delete_conversation_by_id($user->id, $conversationid);
-        } else {
-            throw new moodle_exception("You do not have permission to delete the conversation '$conversationid'");
+        foreach ($conversationids as $conversationid) {
+            if (\core_message\api::can_delete_conversation($user->id, $conversationid)) {
+                \core_message\api::delete_conversation_by_id($user->id, $conversationid);
+            } else {
+                throw new moodle_exception("You do not have permission to delete the conversation '$conversationid'");
+            }
         }
 
         return [];
@@ -2694,7 +2699,7 @@ class core_message_external extends external_api {
      * @return external_description
      * @since 3.6
      */
-    public static function delete_conversation_by_id_returns() {
+    public static function delete_conversations_by_id_returns() {
         return new external_warnings();
     }
 
diff --git a/message/tests/externallib_test.php b/message/tests/externallib_test.php
index 92dae3f1948..16d38817f27 100644
--- a/message/tests/externallib_test.php
+++ b/message/tests/externallib_test.php
@@ -3484,9 +3484,9 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
     }
 
     /**
-     * Test deleting conversation.
+     * Test deleting conversations.
      */
-    public function test_delete_conversation_by_id() {
+    public function test_delete_conversations_by_id() {
         global $DB;
 
         $this->resetAfterTest(true);
@@ -3508,7 +3508,7 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
         $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
 
         // Delete the conversation.
-        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+        core_message_external::delete_conversations_by_id($user1->id, [$conversationid]);
 
         $muas = $DB->get_records('message_user_actions', array(), 'timecreated ASC');
         $this->assertCount(4, $muas);
@@ -3538,9 +3538,9 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
     }
 
     /**
-     * Test deleting conversation as other user.
+     * Test deleting conversations as other user.
      */
-    public function test_delete_conversation_by_id_as_other_user() {
+    public function test_delete_conversations_by_id_as_other_user() {
         global $DB;
 
         $this->resetAfterTest(true);
@@ -3561,7 +3561,7 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
         $conversationid = \core_message\api::get_conversation_between_users([$user1->id, $user2->id]);
 
         // Delete the conversation.
-        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+        core_message_external::delete_conversations_by_id($user1->id, [$conversationid]);
 
         $muas = $DB->get_records('message_user_actions', array(), 'timecreated ASC');
         $this->assertCount(4, $muas);
@@ -3591,9 +3591,9 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
     }
 
     /**
-     * Test deleting conversation as other user without proper capability.
+     * Test deleting conversations as other user without proper capability.
      */
-    public function test_delete_conversation_by_id_as_other_user_without_cap() {
+    public function test_delete_conversations_by_id_as_other_user_without_cap() {
         $this->resetAfterTest(true);
 
         // Create some users.
@@ -3615,13 +3615,13 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
 
         // Ensure an exception is thrown.
         $this->expectException('moodle_exception');
-        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+        core_message_external::delete_conversations_by_id($user1->id, [$conversationid]);
     }
 
     /**
-     * Test deleting conversation with messaging disabled.
+     * Test deleting conversations with messaging disabled.
      */
-    public function test_delete_conversation_by_id_messaging_disabled() {
+    public function test_delete_conversations_by_id_messaging_disabled() {
         global $CFG;
 
         $this->resetAfterTest(true);
@@ -3647,7 +3647,7 @@ class core_message_externallib_testcase extends externallib_advanced_testcase {
 
         // Ensure an exception is thrown.
         $this->expectException('moodle_exception');
-        core_message_external::delete_conversation_by_id($user1->id, $conversationid);
+        core_message_external::delete_conversations_by_id($user1->id, [$conversationid]);
     }
 
     /**
diff --git a/message/upgrade.txt b/message/upgrade.txt
index 969e3b7bfda..c543dc8f2b4 100644
--- a/message/upgrade.txt
+++ b/message/upgrade.txt
@@ -35,7 +35,7 @@ information provided here is intended especially for developers.
   - core_message_external::block_contacts(), please use core_message_external::block_user() instead.
   - core_message_external::unblock_contacts(), please use core_message_external::unblock_user() instead.
   - core_message_external::create_contacts(), please use core_message_external::create_contact_request() instead.
-  - core_message_external::delete_conversation(), please use core_message_external::delete_conversation_by_id() instead.
+  - core_message_external::delete_conversation(), please use core_message_external::delete_conversations_by_id() instead.
 
 === 3.5 ===