MDL-63303 message: add count_contacts api function

message/classes/api.php

@@ -1001,6 +1001,21 @@ class api {
         return [];
     }
 
+    /**
+     * Returns the contacts count.
+     *
+     * @param int $userid The user id
+     * @return array
+     */
+    public static function count_contacts(int $userid) : int {
+        global $DB;
+
+        $sql = "SELECT COUNT(id)
+                  FROM {message_contacts}
+                 WHERE userid = ? OR contactid = ?";
+        return $DB->count_records_sql($sql, [$userid, $userid]);
+    }
+
     /**
      * Returns the an array of the users the given user is in a conversation
      * with who are a contact and the number of unread messages.

message/tests/api_test.php

@@ -5833,6 +5833,35 @@ class core_message_api_testcase extends core_message_messagelib_testcase {
         $this->assertEquals($expected, \core_message\api::count_conversations(...$arguments));
     }
 
+    /**
+     * Test the count_contacts() function.
+     */
+    public function test_count_contacts() {
+        $user1 = self::getDataGenerator()->create_user();
+        $user2 = self::getDataGenerator()->create_user();
+        $user3 = self::getDataGenerator()->create_user();
+
+        $this->assertEquals(0, \core_message\api::count_contacts($user1->id));
+
+        \core_message\api::create_contact_request($user1->id, $user2->id);
+
+        // Still zero until the request is confirmed.
+        $this->assertEquals(0, \core_message\api::count_contacts($user1->id));
+
+        \core_message\api::confirm_contact_request($user1->id, $user2->id);
+
+        $this->assertEquals(1, \core_message\api::count_contacts($user1->id));
+
+        \core_message\api::create_contact_request($user3->id, $user1->id);
+
+        // Still one until the request is confirmed.
+        $this->assertEquals(1, \core_message\api::count_contacts($user1->id));
+
+        \core_message\api::confirm_contact_request($user3->id, $user1->id);
+
+        $this->assertEquals(2, \core_message\api::count_contacts($user1->id));
+    }
+
     /**
      * Comparison function for sorting contacts.
      *