added support for HTTP verb PATCH

To provider better REST API support PATCH method is added which is used
for partial updates, while a PUT should only update whole record.

issues #303
  
An error occurred
 
 and yiisoft/yii#2664
  
An error occurred
 

framework/yii/web/Request.php

@@ -43,7 +43,7 @@ class Request extends \yii\base\Request
 	 */
 	public $enableCookieValidation = true;
 	/**
-	 * @var string|boolean the name of the POST parameter that is used to indicate if a request is a PUT or DELETE
+	 * @var string|boolean the name of the POST parameter that is used to indicate if a request is a PUT, PATCH or DELETE
 	 * request tunneled through POST. Default to '_method'.
 	 * @see getMethod
 	 * @see getRestParams
@@ -73,8 +73,8 @@ class Request extends \yii\base\Request
 	}
 
 	/**
-	 * Returns the method of the current request (e.g. GET, POST, HEAD, PUT, DELETE).
-	 * @return string request method, such as GET, POST, HEAD, PUT, DELETE.
+	 * Returns the method of the current request (e.g. GET, POST, HEAD, PUT, PATCH, DELETE).
+	 * @return string request method, such as GET, POST, HEAD, PUT, PATCH, DELETE.
 	 * The value returned is turned into upper case.
 	 */
 	public function getMethod()
@@ -114,6 +114,15 @@ class Request extends \yii\base\Request
 	}
 
 	/**
+	 * Returns whether this is a PATCH request.
+	 * @return boolean whether this is a PATCH request.
+	 */
+	public function getIsPatch()
+	{
+		return $this->getMethod() === 'PATCH';
+	}
+
+	/**
 	 * Returns whether this is an AJAX (XMLHttpRequest) request.
 	 * @return boolean whether this is an AJAX (XMLHttpRequest) request.
 	 */
@@ -239,6 +248,17 @@ class Request extends \yii\base\Request
 		return $this->getIsPut() ? $this->getRestParam($name, $defaultValue) : null;
 	}
 
+	/**
+	 * Returns the named PATCH parameter value.
+	 * @param string $name the PATCH parameter name
+	 * @param mixed $defaultValue the default parameter value if the PATCH parameter does not exist.
+	 * @return mixed the PATCH parameter value
+	 */
+	public function getPatch($name, $defaultValue = null)
+	{
+		return $this->getIsPatch() ? $this->getRestParam($name, $defaultValue) : null;
+	}
+
 	private $_hostInfo;
 
 	/**
@@ -914,7 +934,7 @@ class Request extends \yii\base\Request
 			return;
 		}
 		$method = $this->getMethod();
-		if ($method === 'POST' || $method === 'PUT' || $method === 'DELETE') {
+		if ($method === 'POST' || $method === 'PUT' || $method === 'PATCH' || $method === 'DELETE') {
 			$cookies = $this->getCookies();
 			switch ($method) {
 				case 'POST':
@@ -923,6 +943,9 @@ class Request extends \yii\base\Request
 				case 'PUT':
 					$token = $this->getPut($this->csrfTokenName);
 					break;
+				case 'PATCH':
+					$token = $this->getPatch($this->csrfTokenName);
+					break;
 				case 'DELETE':
 					$token = $this->getDelete($this->csrfTokenName);
 			}

framework/yii/web/UrlManager.php

@@ -49,7 +49,7 @@ class UrlManager extends Component
 	 * For example, `'PUT post/<id:\d+>' => 'post/update'`.
 	 * You may specify multiple verbs by separating them with comma
 	 * like this: `'POST,PUT post/index' => 'post/create'`.
-	 * The supported verbs in the shortcut format are: GET, HEAD, POST, PUT and DELETE.
+	 * The supported verbs in the shortcut format are: GET, HEAD, POST, PUT, PATCH and DELETE.
 	 * Note that [[UrlRule::mode|mode]] will be set to PARSING_ONLY when specifying verb in this way
 	 * so you normally would not specify a verb for normal GET request.
 	 *
@@ -142,7 +142,7 @@ class UrlManager extends Component
 				$rule = array(
 					'route' => $rule,
 				);
-				if (preg_match('/^((?:(GET|HEAD|POST|PUT|DELETE),)*(GET|HEAD|POST|PUT|DELETE))\s+(.*)$/', $key, $matches)) {
+				if (preg_match('/^((?:(GET|HEAD|POST|PUT|PATCH|DELETE),)*(GET|HEAD|POST|PUT|PATCH|DELETE))\s+(.*)$/', $key, $matches)) {
 					$rule['verb'] = explode(',', $matches[1]);
 					$rule['mode'] = UrlRule::PARSING_ONLY;
 					$key = $matches[4];