diff --git a/lib/db/services.php b/lib/db/services.php
index 08195cc6bd1..bedc6c25f6f 100644
--- a/lib/db/services.php
+++ b/lib/db/services.php
@@ -825,7 +825,8 @@ $functions = array(
         'classname' => 'core_message_external',
         'methodname' => 'block_contacts',
         'classpath' => 'message/externallib.php',
-        'description' => 'Block contacts',
+        'description' => '** DEPRECATED ** Please do not call this function any more.
+                          Block contacts',
         'type' => 'write',
         'ajax' => true,
         'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
@@ -834,11 +835,11 @@ $functions = array(
         'classname' => 'core_message_external',
         'methodname' => 'create_contacts',
         'classpath' => 'message/externallib.php',
-        'description' => 'Add contacts to the contact list',
+        'description' => '** DEPRECATED ** Please do not call this function any more.
+                          Add contacts to the contact list',
         'type' => 'write',
         'ajax' => true,
         'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
-        'ajax' => true,
     ),
     'core_message_delete_contacts' => array(
         'classname' => 'core_message_external',
@@ -848,7 +849,6 @@ $functions = array(
         'type' => 'write',
         'ajax' => true,
         'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
-        'ajax' => true,
     ),
     'core_message_delete_conversation' => array(
         'classname' => 'core_message_external',
@@ -1047,7 +1047,8 @@ $functions = array(
         'classname' => 'core_message_external',
         'methodname' => 'unblock_contacts',
         'classpath' => 'message/externallib.php',
-        'description' => 'Unblock contacts',
+        'description' => '** DEPRECATED ** Please do not call this function any more.
+                         Unblock contacts',
         'type' => 'write',
         'ajax' => true,
         'services' => array(MOODLE_OFFICIAL_MOBILE_SERVICE),
diff --git a/lib/deprecatedlib.php b/lib/deprecatedlib.php
index ca248e71620..44e8b8b0852 100644
--- a/lib/deprecatedlib.php
+++ b/lib/deprecatedlib.php
@@ -3455,3 +3455,159 @@ function get_roles_with_assignment_on_context(context $context) {
 
     return get_roles_used_in_context($context, false);
 }
+
+/**
+ * Add the selected user as a contact for the current user
+ *
+ * @deprecated since Moodle 3.6
+ * @param int $contactid the ID of the user to add as a contact
+ * @param int $blocked 1 if you wish to block the contact
+ * @param int $userid the user ID of the user we want to add the contact for, defaults to current user if not specified.
+ * @return bool/int false if the $contactid isnt a valid user id. True if no changes made.
+ *                  Otherwise returns the result of update_record() or insert_record()
+ */
+function message_add_contact($contactid, $blocked = 0, $userid = 0) {
+    debugging('message_add_contact() is deprecated. Please use \core_message\api::create_contact_request() instead. ' .
+        'If you wish to block or unblock a user please use \core_message\api::is_blocked() and ' .
+        '\core_message\api::block_user() or \core_message\api::unblock_user() respectively.', DEBUG_DEVELOPER);
+
+    global $USER, $DB;
+
+    if (!$DB->record_exists('user', array('id' => $contactid))) {
+        return false;
+    }
+
+    if (empty($userid)) {
+        $userid = $USER->id;
+    }
+
+    // Check if a record already exists as we may be changing blocking status.
+    if (\core_message\api::is_contact($userid, $contactid)) {
+        $isblocked = \core_message\api::is_blocked($userid, $contactid);
+        // Check if blocking status has been changed.
+        if ($isblocked != $blocked) {
+            if ($blocked == 1) {
+                if (!$isblocked) {
+                    \core_message\api::block_user($userid, $contactid);
+                }
+            } else {
+                \core_message\api::unblock_user($userid, $contactid);
+            }
+
+            return true;
+        } else {
+            // No change to blocking status.
+            return true;
+        }
+    } else {
+        if ($blocked == 1) {
+            if (!\core_message\api::is_blocked($userid, $contactid)) {
+                \core_message\api::block_user($userid, $contactid);
+            }
+        } else {
+            \core_message\api::unblock_user($userid, $contactid);
+            if (!\core_message\api::does_contact_request_exist($userid, $contactid)) {
+                \core_message\api::create_contact_request($userid, $contactid);
+            }
+        }
+
+        return true;
+    }
+}
+
+/**
+ * Remove a contact.
+ *
+ * @deprecated since Moodle 3.6
+ * @param int $contactid the user ID of the contact to remove
+ * @param int $userid the user ID of the user we want to remove the contacts for, defaults to current user if not specified.
+ * @return bool returns the result of delete_records()
+ */
+function message_remove_contact($contactid, $userid = 0) {
+    debugging('message_remove_contact() is deprecated. Please use \core_message\api::remove_contact() instead.',
+        DEBUG_DEVELOPER);
+
+    global $USER;
+
+    if (empty($userid)) {
+        $userid = $USER->id;
+    }
+
+    \core_message\api::remove_contact($userid, $contactid);
+
+    return true;
+}
+
+/**
+ * Unblock a contact.
+ *
+ * @deprecated since Moodle 3.6
+ * @param int $contactid the user ID of the contact to unblock
+ * @param int $userid the user ID of the user we want to unblock the contact for, defaults to current user
+ *  if not specified.
+ * @return bool returns the result of delete_records()
+ */
+function message_unblock_contact($contactid, $userid = 0) {
+    debugging('message_unblock_contact() is deprecated. Please use \core_message\api::unblock_user() instead.',
+        DEBUG_DEVELOPER);
+
+    global $DB, $USER;
+
+    if (!$DB->record_exists('user', array('id' => $contactid))) {
+        return false;
+    }
+
+    if (empty($userid)) {
+        $userid = $USER->id;
+    }
+
+    \core_message\api::unblock_user($userid, $contactid);
+
+    return true;
+}
+
+/**
+ * Block a user.
+ *
+ * @deprecated since Moodle 3.6
+ * @param int $contactid the user ID of the user to block
+ * @param int $userid the user ID of the user we want to unblock the contact for, defaults to current user
+ *  if not specified.
+ * @return bool
+ */
+function message_block_contact($contactid, $userid = 0) {
+    debugging('message_block_contact() is deprecated. Please use \core_message\api::is_blocked() and ' .
+        '\core_message\api::block_user() instead.', DEBUG_DEVELOPER);
+
+    global $DB, $USER;
+
+    if (!$DB->record_exists('user', array('id' => $contactid))) {
+        return false;
+    }
+
+    if (empty($userid)) {
+        $userid = $USER->id;
+    }
+
+    if (!\core_message\api::is_blocked($userid, $contactid)) {
+        \core_message\api::block_user($userid, $contactid);
+    }
+
+    return true;
+}
+
+/**
+ * Load a user's contact record
+ *
+ * @deprecated since Moodle 3.6
+ * @param int $contactid the user ID of the user whose contact record you want
+ * @return array message contacts
+ */
+function message_get_contact($contactid) {
+    debugging('message_get_contact() is deprecated. Please use \core_message\api::get_contact() instead.',
+        DEBUG_DEVELOPER);
+
+    global $USER;
+
+    return \core_message\api::get_contact($USER->id, $contactid);
+}
diff --git a/message/classes/api.php b/message/classes/api.php
index 51a067a7fc5..ed700f9271d 100644
--- a/message/classes/api.php
+++ b/message/classes/api.php
@@ -1287,4 +1287,252 @@ class api {
 
         return $conversation->id;
     }
+
+    /**
+     * Handles creating a contact request.
+     *
+     * @param int $userid The id of the user who is creating the contact request
+     * @param int $requesteduserid The id of the user being requested
+     */
+    public static function create_contact_request(int $userid, int $requesteduserid) {
+        global $DB;
+
+        $request = new \stdClass();
+        $request->userid = $userid;
+        $request->requesteduserid = $requesteduserid;
+        $request->timecreated = time();
+
+        $DB->insert_record('message_contact_requests', $request);
+    }
+
+
+    /**
+     * Handles confirming a contact request.
+     *
+     * @param int $userid The id of the user who created the contact request
+     * @param int $requesteduserid The id of the user confirming the request
+     */
+    public static function confirm_contact_request(int $userid, int $requesteduserid) {
+        global $DB;
+
+        if ($request = $DB->get_record('message_contact_requests', ['userid' => $userid,
+                'requesteduserid' => $requesteduserid])) {
+            self::add_contact($userid, $requesteduserid);
+
+            $DB->delete_records('message_contact_requests', ['id' => $request->id]);
+        }
+    }
+
+    /**
+     * Handles declining a contact request.
+     *
+     * @param int $userid The id of the user who created the contact request
+     * @param int $requesteduserid The id of the user declining the request
+     */
+    public static function decline_contact_request(int $userid, int $requesteduserid) {
+        global $DB;
+
+        if ($request = $DB->get_record('message_contact_requests', ['userid' => $userid,
+                'requesteduserid' => $requesteduserid])) {
+            $DB->delete_records('message_contact_requests', ['id' => $request->id]);
+        }
+    }
+
+    /**
+     * Handles returning the contact requests for a user.
+     *
+     * This also includes the user data necessary to display information
+     * about the user.
+     *
+     * It will not include blocked users.
+     *
+     * @param int $userid
+     * @return array The list of contact requests
+     */
+    public static function get_contact_requests(int $userid) : array {
+        global $DB;
+
+        // Used to search for contacts.
+        $ufields = \user_picture::fields('u');
+
+        $sql = "SELECT $ufields, mcr.id as contactrequestid
+                  FROM {user} u
+                  JOIN {message_contact_requests} mcr
+                    ON u.id = mcr.userid
+             LEFT JOIN {message_users_blocked} mub
+                    ON (mub.userid = ? AND mub.blockeduserid = u.id)
+                 WHERE mcr.requesteduserid = ?
+                   AND u.deleted = 0
+                   AND mub.id is NULL
+              ORDER BY mcr.timecreated DESC";
+
+        return $DB->get_records_sql($sql, [$userid, $userid]);
+    }
+
+    /**
+     * Handles adding a contact.
+     *
+     * @param int $userid The id of the user who requested to be a contact
+     * @param int $contactid The id of the contact
+     */
+    public static function add_contact(int $userid, int $contactid) {
+        global $DB;
+
+        $messagecontact = new \stdClass();
+        $messagecontact->userid = $userid;
+        $messagecontact->contactid = $contactid;
+        $messagecontact->timecreated = time();
+        $messagecontact->id = $DB->insert_record('message_contacts', $messagecontact);
+
+        $eventparams = [
+            'objectid' => $messagecontact->id,
+            'userid' => $userid,
+            'relateduserid' => $contactid,
+            'context' => \context_user::instance($userid)
+        ];
+        $event = \core\event\message_contact_added::create($eventparams);
+        $event->add_record_snapshot('message_contacts', $messagecontact);
+        $event->trigger();
+    }
+
+    /**
+     * Handles removing a contact.
+     *
+     * @param int $userid The id of the user who is removing a user as a contact
+     * @param int $contactid The id of the user to be removed as a contact
+     */
+    public static function remove_contact(int $userid, int $contactid) {
+        global $DB;
+
+        if ($contact = self::get_contact($userid, $contactid)) {
+            $DB->delete_records('message_contacts', ['id' => $contact->id]);
+
+            $event = \core\event\message_contact_removed::create(array(
+                'objectid' => $contact->id,
+                'userid' => $userid,
+                'relateduserid' => $contactid,
+                'context' => \context_user::instance($userid)
+            ));
+            $event->add_record_snapshot('message_contacts', $contact);
+            $event->trigger();
+        }
+    }
+
+    /**
+     * Handles blocking a user.
+     *
+     * @param int $userid The id of the user who is blocking
+     * @param int $usertoblockid The id of the user being blocked
+     */
+    public static function block_user(int $userid, int $usertoblockid) {
+        global $DB;
+
+        $blocked = new \stdClass();
+        $blocked->userid = $userid;
+        $blocked->blockeduserid = $usertoblockid;
+        $blocked->timecreated = time();
+        $blocked->id = $DB->insert_record('message_users_blocked', $blocked);
+
+        // Trigger event for blocking a contact.
+        $event = \core\event\message_user_blocked::create(array(
+            'objectid' => $blocked->id,
+            'userid' => $userid,
+            'relateduserid' => $usertoblockid,
+            'context' => \context_user::instance($userid)
+        ));
+        $event->add_record_snapshot('message_users_blocked', $blocked);
+        $event->trigger();
+    }
+
+    /**
+     * Handles unblocking a user.
+     *
+     * @param int $userid The id of the user who is unblocking
+     * @param int $usertounblockid The id of the user being unblocked
+     */
+    public static function unblock_user(int $userid, int $usertounblockid) {
+        global $DB;
+
+        if ($blockeduser = $DB->get_record('message_users_blocked',
+                ['userid' => $userid, 'blockeduserid' => $usertounblockid])) {
+            $DB->delete_records('message_users_blocked', ['id' => $blockeduser->id]);
+
+            // Trigger event for unblocking a contact.
+            $event = \core\event\message_user_unblocked::create(array(
+                'objectid' => $blockeduser->id,
+                'userid' => $userid,
+                'relateduserid' => $usertounblockid,
+                'context' => \context_user::instance($userid)
+            ));
+            $event->add_record_snapshot('message_users_blocked', $blockeduser);
+            $event->trigger();
+        }
+    }
+
+    /**
+     * Checks if users are already contacts.
+     *
+     * @param int $userid The id of one of the users
+     * @param int $contactid The id of the other user
+     * @return bool Returns true if they are a contact, false otherwise
+     */
+    public static function is_contact(int $userid, int $contactid) : bool {
+        global $DB;
+
+        $sql = "SELECT id
+                  FROM {message_contacts} mc
+                 WHERE (mc.userid = ? AND mc.contactid = ?)
+                    OR (mc.userid = ? AND mc.contactid = ?)";
+        return $DB->record_exists_sql($sql, [$userid, $contactid, $contactid, $userid]);
+    }
+
+    /**
+     * Returns the row in the database table message_contacts that represents the contact between two people.
+     *
+     * @param int $userid The id of one of the users
+     * @param int $contactid The id of the other user
+     * @return mixed A fieldset object containing the record, false otherwise
+     */
+    public static function get_contact(int $userid, int $contactid) {
+        global $DB;
+
+        $sql = "SELECT mc.*
+                  FROM {message_contacts} mc
+                 WHERE (mc.userid = ? AND mc.contactid = ?)
+                    OR (mc.userid = ? AND mc.contactid = ?)";
+        return $DB->get_record_sql($sql, [$userid, $contactid, $contactid, $userid]);
+    }
+
+    /**
+     * Checks if a user is already blocked.
+     *
+     * This is different than self::is_user_blocked() as it does not check any capabilities.
+     * It simply checks if an entry exists in the DB.
+     *
+     * @param int $userid
+     * @param int $blockeduserid
+     * @return bool Returns true if they are a blocked, false otherwise
+     */
+    public static function is_blocked(int $userid, int $blockeduserid) : bool {
+        global $DB;
+
+        return $DB->record_exists('message_users_blocked', ['userid' => $userid, 'blockeduserid' => $blockeduserid]);
+    }
+
+    /**
+     * Checks if a contact request already exists between users.
+     *
+     * @param int $userid The id of the user who is creating the contact request
+     * @param int $requesteduserid The id of the user being requested
+     * @return bool Returns true if a contact request exists, false otherwise
+     */
+    public static function does_contact_request_exist(int $userid, int $requesteduserid) : bool {
+        global $DB;
+
+        $sql = "SELECT id
+                  FROM {message_contact_requests} mcr
+                 WHERE (mcr.userid = ? AND mcr.requesteduserid = ?)
+                    OR (mcr.userid = ? AND mcr.requesteduserid = ?)";
+        return $DB->record_exists_sql($sql, [$userid, $requesteduserid, $requesteduserid, $userid]);
+    }
 }
diff --git a/message/externallib.php b/message/externallib.php
index 5151adb5e31..43c94f394e0 100644
--- a/message/externallib.php
+++ b/message/externallib.php
@@ -191,6 +191,7 @@ class core_message_external extends external_api {
     /**
      * Create contacts parameters description.
      *
+     * @deprecated since Moodle 3.6
      * @return external_function_parameters
      * @since Moodle 2.5
      */
@@ -210,6 +211,7 @@ class core_message_external extends external_api {
     /**
      * Create contacts.
      *
+     * @deprecated since Moodle 3.6
      * @param array $userids array of user IDs.
      * @param int $userid The id of the user we are creating the contacts for
      * @return external_description
@@ -256,6 +258,7 @@ class core_message_external extends external_api {
     /**
      * Create contacts return description.
      *
+     * @deprecated since Moodle 3.6
      * @return external_description
      * @since Moodle 2.5
      */
@@ -263,6 +266,15 @@ class core_message_external extends external_api {
         return new external_warnings();
     }
 
+    /**
+     * Marking the method as deprecated.
+     *
+     * @return bool
+     */
+    public static function create_contacts_is_deprecated() {
+        return true;
+    }
+
     /**
      * Delete contacts parameters description.
      *
@@ -334,6 +346,7 @@ class core_message_external extends external_api {
     /**
      * Block contacts parameters description.
      *
+     * @deprecated since Moodle 3.6
      * @return external_function_parameters
      * @since Moodle 2.5
      */
@@ -353,6 +366,7 @@ class core_message_external extends external_api {
     /**
      * Block contacts.
      *
+     * @deprecated since Moodle 3.6
      * @param array $userids array of user IDs.
      * @param int $userid The id of the user we are blocking the contacts for
      * @return external_description
@@ -399,6 +413,7 @@ class core_message_external extends external_api {
     /**
      * Block contacts return description.
      *
+     * @deprecated since Moodle 3.6
      * @return external_description
      * @since Moodle 2.5
      */
@@ -406,9 +421,19 @@ class core_message_external extends external_api {
         return new external_warnings();
     }
 
+    /**
+     * Marking the method as deprecated.
+     *
+     * @return bool
+     */
+    public static function block_contacts_is_deprecated() {
+        return true;
+    }
+
     /**
      * Unblock contacts parameters description.
      *
+     * @deprecated since Moodle 3.6
      * @return external_function_parameters
      * @since Moodle 2.5
      */
@@ -428,6 +453,7 @@ class core_message_external extends external_api {
     /**
      * Unblock contacts.
      *
+     * @deprecated since Moodle 3.6
      * @param array $userids array of user IDs.
      * @param int $userid The id of the user we are unblocking the contacts for
      * @return null
@@ -467,6 +493,7 @@ class core_message_external extends external_api {
     /**
      * Unblock contacts return description.
      *
+     * @deprecated since Moodle 3.6
      * @return external_description
      * @since Moodle 2.5
      */
@@ -474,6 +501,15 @@ class core_message_external extends external_api {
         return null;
     }
 
+    /**
+     * Marking the method as deprecated.
+     *
+     * @return bool
+     */
+    public static function unblock_contacts_is_deprecated() {
+        return true;
+    }
+
     /**
      * Return the structure of a message area contact.
      *
diff --git a/message/lib.php b/message/lib.php
index a3f99fc96da..488e5f36627 100644
--- a/message/lib.php
+++ b/message/lib.php
@@ -151,156 +151,6 @@ function message_format_message_text($message, $forcetexttohtml = false) {
     return format_text($messagetext, $format, $options);
 }
 
-/**
- * Add the selected user as a contact for the current user
- *
- * @param int $contactid the ID of the user to add as a contact
- * @param int $blocked 1 if you wish to block the contact
- * @param int $userid the user ID of the user we want to add the contact for, defaults to current user if not specified.
- * @return bool/int false if the $contactid isnt a valid user id. True if no changes made.
- *                  Otherwise returns the result of update_record() or insert_record()
- */
-function message_add_contact($contactid, $blocked = 0, $userid = 0) {
-    global $USER, $DB;
-
-    if (!$DB->record_exists('user', array('id' => $contactid))) { // invalid userid
-        return false;
-    }
-
-    if (empty($userid)) {
-        $userid = $USER->id;
-    }
-
-    // Check if a record already exists as we may be changing blocking status.
-    if (($contact = $DB->get_record('message_contacts', array('userid' => $userid, 'contactid' => $contactid))) !== false) {
-        // Check if blocking status has been changed.
-        if ($contact->blocked != $blocked) {
-            $contact->blocked = $blocked;
-            $DB->update_record('message_contacts', $contact);
-
-            if ($blocked == 1) {
-                // Trigger event for blocking a contact.
-                $event = \core\event\message_contact_blocked::create(array(
-                    'objectid' => $contact->id,
-                    'userid' => $contact->userid,
-                    'relateduserid' => $contact->contactid,
-                    'context'  => context_user::instance($contact->userid)
-                ));
-                $event->add_record_snapshot('message_contacts', $contact);
-                $event->trigger();
-            } else {
-                // Trigger event for unblocking a contact.
-                $event = \core\event\message_contact_unblocked::create(array(
-                    'objectid' => $contact->id,
-                    'userid' => $contact->userid,
-                    'relateduserid' => $contact->contactid,
-                    'context'  => context_user::instance($contact->userid)
-                ));
-                $event->add_record_snapshot('message_contacts', $contact);
-                $event->trigger();
-            }
-
-            return true;
-        } else {
-            // No change to blocking status.
-            return true;
-        }
-
-    } else {
-        // New contact record.
-        $contact = new stdClass();
-        $contact->userid = $userid;
-        $contact->contactid = $contactid;
-        $contact->blocked = $blocked;
-        $contact->id = $DB->insert_record('message_contacts', $contact);
-
-        $eventparams = array(
-            'objectid' => $contact->id,
-            'userid' => $contact->userid,
-            'relateduserid' => $contact->contactid,
-            'context'  => context_user::instance($contact->userid)
-        );
-
-        if ($blocked) {
-            $event = \core\event\message_contact_blocked::create($eventparams);
-        } else {
-            $event = \core\event\message_contact_added::create($eventparams);
-        }
-        // Trigger event.
-        $event->trigger();
-
-        return true;
-    }
-}
-
-/**
- * remove a contact
- *
- * @param int $contactid the user ID of the contact to remove
- * @param int $userid the user ID of the user we want to remove the contacts for, defaults to current user if not specified.
- * @return bool returns the result of delete_records()
- */
-function message_remove_contact($contactid, $userid = 0) {
-    global $USER, $DB;
-
-    if (empty($userid)) {
-        $userid = $USER->id;
-    }
-
-    if ($contact = $DB->get_record('message_contacts', array('userid' => $userid, 'contactid' => $contactid))) {
-        $DB->delete_records('message_contacts', array('id' => $contact->id));
-
-        // Trigger event for removing a contact.
-        $event = \core\event\message_contact_removed::create(array(
-            'objectid' => $contact->id,
-            'userid' => $contact->userid,
-            'relateduserid' => $contact->contactid,
-            'context'  => context_user::instance($contact->userid)
-        ));
-        $event->add_record_snapshot('message_contacts', $contact);
-        $event->trigger();
-
-        return true;
-    }
-
-    return false;
-}
-
-/**
- * Unblock a contact. Note that this reverts the previously blocked user back to a non-contact.
- *
- * @param int $contactid the user ID of the contact to unblock
- * @param int $userid the user ID of the user we want to unblock the contact for, defaults to current user
- *  if not specified.
- * @return bool returns the result of delete_records()
- */
-function message_unblock_contact($contactid, $userid = 0) {
-    return message_add_contact($contactid, 0, $userid);
-}
-
-/**
- * Block a user.
- *
- * @param int $contactid the user ID of the user to block
- * @param int $userid the user ID of the user we want to unblock the contact for, defaults to current user
- *  if not specified.
- * @return bool
- */
-function message_block_contact($contactid, $userid = 0) {
-    return message_add_contact($contactid, 1, $userid);
-}
-
-/**
- * Load a user's contact record
- *
- * @param int $contactid the user ID of the user whose contact record you want
- * @return array message contacts
- */
-function message_get_contact($contactid) {
-    global $USER, $DB;
-    return $DB->get_record('message_contacts', array('userid' => $USER->id, 'contactid' => $contactid));
-}
-
 /**
  * Search through course users.
  *
diff --git a/message/tests/api_test.php b/message/tests/api_test.php
index 42f8192c875..8a729a367d5 100644
--- a/message/tests/api_test.php
+++ b/message/tests/api_test.php
@@ -1939,4 +1939,232 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         $this->assertEquals($conversationid,
             \core_message\api::get_conversation_between_users([$user1->id, $user2->id]));
     }
+
+    /**
+     * Test creating a contact request.
+     */
+    public function test_create_contact_request() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::create_contact_request($user1->id, $user2->id);
+
+        $request = $DB->get_records('message_contact_requests');
+
+        $this->assertCount(1, $request);
+
+        $request = reset($request);
+
+        $this->assertEquals($user1->id, $request->userid);
+        $this->assertEquals($user2->id, $request->requesteduserid);
+    }
+
+    /**
+     * Test confirming a contact request.
+     */
+    public function test_confirm_contact_request() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::create_contact_request($user1->id, $user2->id);
+
+        \core_message\api::confirm_contact_request($user1->id, $user2->id);
+
+        $this->assertEquals(0, $DB->count_records('message_contact_requests'));
+
+        $contact = $DB->get_records('message_contacts');
+
+        $this->assertCount(1, $contact);
+
+        $contact = reset($contact);
+
+        $this->assertEquals($user1->id, $contact->userid);
+        $this->assertEquals($user2->id, $contact->contactid);
+    }
+
+    /**
+     * Test declining a contact request.
+     */
+    public function test_decline_contact_request() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::create_contact_request($user1->id, $user2->id);
+
+        \core_message\api::decline_contact_request($user1->id, $user2->id);
+
+        $this->assertEquals(0, $DB->count_records('message_contact_requests'));
+        $this->assertEquals(0, $DB->count_records('message_contacts'));
+    }
+
+    /**
+     * Test retrieving contact requests.
+     */
+    public function test_get_contact_requests() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        // Block one user, their request should not show up.
+        \core_message\api::block_user($user1->id, $user3->id);
+
+        \core_message\api::create_contact_request($user2->id, $user1->id);
+        \core_message\api::create_contact_request($user3->id, $user1->id);
+
+        $requests = \core_message\api::get_contact_requests($user1->id);
+
+        $this->assertCount(1, $requests);
+
+        $request = reset($requests);
+
+        $this->assertEquals($user2->id, $request->id);
+        $this->assertEquals($user2->picture, $request->picture);
+        $this->assertEquals($user2->firstname, $request->firstname);
+        $this->assertEquals($user2->lastname, $request->lastname);
+        $this->assertEquals($user2->firstnamephonetic, $request->firstnamephonetic);
+        $this->assertEquals($user2->lastnamephonetic, $request->lastnamephonetic);
+        $this->assertEquals($user2->middlename, $request->middlename);
+        $this->assertEquals($user2->alternatename, $request->alternatename);
+        $this->assertEquals($user2->email, $request->email);
+    }
+
+    /**
+     * Test adding contacts.
+     */
+    public function test_add_contact() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::add_contact($user1->id, $user2->id);
+
+        $contact = $DB->get_records('message_contacts');
+
+        $this->assertCount(1, $contact);
+
+        $contact = reset($contact);
+
+        $this->assertEquals($user1->id, $contact->userid);
+        $this->assertEquals($user2->id, $contact->contactid);
+    }
+
+    /**
+     * Test removing contacts.
+     */
+    public function test_remove_contact() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::add_contact($user1->id, $user2->id);
+        \core_message\api::remove_contact($user1->id, $user2->id);
+
+        $this->assertEquals(0, $DB->count_records('message_contacts'));
+    }
+
+    /**
+     * Test blocking users.
+     */
+    public function test_block_user() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::block_user($user1->id, $user2->id);
+
+        $blockedusers = $DB->get_records('message_users_blocked');
+
+        $this->assertCount(1, $blockedusers);
+
+        $blockeduser = reset($blockedusers);
+
+        $this->assertEquals($user1->id, $blockeduser->userid);
+        $this->assertEquals($user2->id, $blockeduser->blockeduserid);
+    }
+
+    /**
+     * Test unblocking users.
+     */
+    public function test_unblock_user() {
+        global $DB;
+
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::block_user($user1->id, $user2->id);
+        \core_message\api::unblock_user($user1->id, $user2->id);
+
+        $this->assertEquals(0, $DB->count_records('message_users_blocked'));
+    }
+
+    /**
+     * Test is contact check.
+     */
+    public function test_is_contact() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        \core_message\api::add_contact($user1->id, $user2->id);
+
+        $this->assertTrue(\core_message\api::is_contact($user1->id, $user2->id));
+        $this->assertTrue(\core_message\api::is_contact($user2->id, $user1->id));
+        $this->assertFalse(\core_message\api::is_contact($user2->id, $user3->id));
+    }
+
+    /**
+     * Test get contact.
+     */
+    public function test_get_contact() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        \core_message\api::add_contact($user1->id, $user2->id);
+
+        $contact = \core_message\api::get_contact($user1->id, $user2->id);
+
+        $this->assertEquals($user1->id, $contact->userid);
+        $this->assertEquals($user2->id, $contact->contactid);
+    }
+
+    /**
+     * Test is blocked checked.
+     */
+    public function test_is_blocked() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        $this->assertFalse(\core_message\api::is_blocked($user1->id, $user2->id));
+        $this->assertFalse(\core_message\api::is_blocked($user2->id, $user1->id));
+
+        \core_message\api::block_user($user1->id, $user2->id);
+
+        $this->assertTrue(\core_message\api::is_blocked($user1->id, $user2->id));
+        $this->assertFalse(\core_message\api::is_blocked($user2->id, $user1->id));
+    }
+
+    /**
+     * Test the contact request exist check.
+     */
+    public function test_does_contact_request_exist() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+
+        $this->assertFalse(\core_message\api::does_contact_request_exist($user1->id, $user2->id));
+        $this->assertFalse(\core_message\api::does_contact_request_exist($user2->id, $user1->id));
+
+        \core_message\api::create_contact_request($user1->id, $user2->id);
+
+        $this->assertTrue(\core_message\api::does_contact_request_exist($user1->id, $user2->id));
+        $this->assertTrue(\core_message\api::does_contact_request_exist($user2->id, $user1->id));
+    }
 }