Added method to get the exception type

src/OAuth2/AuthServer.php

@@ -67,7 +67,7 @@ class AuthServer
      * Exception error codes
      * @var array
      */
-    protected $exceptionCodes = array(
+    protected static $exceptionCodes = array(
         0   =>  'invalid_request',
         1   =>  'unauthorized_client',
         2   =>  'access_denied',
@@ -110,6 +110,17 @@ class AuthServer
         return self::$exceptionMessages[$error];
     }
 
+    /**
+     * Get an exception code
+     *
+     * @param  integer $code The exception code
+     * @return string        The exception code type
+     */
+    public static function getExceptionType($code = 0)
+    {
+        return self::$exceptionCodes[$code];
+    }
+
     /**
      * Create a new OAuth2 authentication server
      *

tests/authentication/AuthServerTest.php

@@ -45,6 +45,11 @@ class Authentication_Server_test extends PHPUnit_Framework_TestCase
         $this->assertEquals($v['access_denied'], $m);
     }
 
+    public function test_getExceptionCode()
+    {
+        $this->assertEquals('access_denied', OAuth2\AuthServer::getExceptionType(2));
+    }
+
     public function test_hasGrantType()
     {
         $this->assertFalse(OAuth2\AuthServer::hasGrantType('test'));