Merge pull request #5 from activecollab/feature/silence-exceptions

Feature/silence exceptions

Author: ilijastuden

README.md

@@ -18,3 +18,17 @@ All of these methods accept three parameters:
 1. `$request` (`\Psr\Http\Message\ServerRequestInterface` instance)
 2. `$param_name` (string)
 3. `$default` (mixed, `NULL` by default)
+
+## Exception Handling
+
+When action fails due to an exception, system will return 500 HTTP error, with a message that does not expose any of the system details. 
+
+This is done in such a way that new `RuntimeException` is constructed, with generic error message, and real exception is passed as `$previous` constructor argument of the new exception. If you have your system configured so exceptions are fully described when 500 errors are rendered (in debug mode for example), you'll be able to access original exception detials like that.
+
+To change default exception message, call `setLogExceptionMessage()` controller method:
+
+```php
+$controller->setLogExceptionMessage('Something weird happened: {exception}');
+```
+
+If `$logger` is added to the controller (during construction or later on), all exceptions that actions throw will be logged with error level.

src/Controller.php

@@ -16,9 +16,11 @@
 use ActiveCollab\Controller\ResultEncoder\ResultEncoderInterface;
 use Exception;
 use Interop\Container\ContainerInterface;
+use InvalidArgumentException;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
 use Psr\Log\LoggerInterface;
+use RuntimeException;
 
 /**
  * @package ActiveCollab\Controller
@@ -32,14 +34,31 @@ abstract class Controller implements ContainerAccessInterface, ControllerInterfa
      */
     private $result_encoder;
 
+    /**
+     * @var LoggerInterface
+     */
+    private $logger;
+
+    /**
+     * @var string
+     */
+    private $action_exception_message = 'Whoops, something went wrong...';
+
+    /**
+     * @var string
+     */
+    private $log_exception_message = 'Controller action aborted with an exception';
+
     /**
      * @param ContainerInterface     $container
      * @param ResultEncoderInterface $result_encoder
+     * @param LoggerInterface|null   $logger
      */
-    public function __construct(ContainerInterface &$container, ResultEncoderInterface &$result_encoder)
+    public function __construct(ContainerInterface &$container, ResultEncoderInterface &$result_encoder, LoggerInterface $logger = null)
     {
         $this->setContainer($container);
         $this->setResultEncoder($result_encoder);
+        $this->setLogger($logger);
     }
 
     /**
@@ -60,6 +79,68 @@ public function &setResultEncoder(ResultEncoderInterface $result_encoder)
         return $this;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function getLogger()
+    {
+        return $this->logger;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function &setLogger(LoggerInterface $logger = null)
+    {
+        $this->logger = $logger;
+
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getClientFacingExceptionMessage()
+    {
+        return $this->action_exception_message;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function &setClientFacingExceptionMessage($message)
+    {
+        if (empty($message)) {
+            throw new InvalidArgumentException("Client facing exception message can't be empty");
+        }
+
+        $this->action_exception_message = $message;
+
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getLogExceptionMessage()
+    {
+        return $this->log_exception_message;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function &setLogExceptionMessage($message)
+    {
+        if (empty($message)) {
+            throw new InvalidArgumentException("Log exception message can't be empty");
+        }
+
+        $this->log_exception_message = $message;
+
+        return $this;
+    }
+
     /**
      * Run before every action.
      *
@@ -114,13 +195,17 @@ public function __invoke(ServerRequestInterface $request, ResponseInterface $res
                     try {
                         return $this->getResultEncoder()->encode(call_user_func([&$this, $action], $request, $arguments), $request, $response);
                     } catch (Exception $e) {
-                        if ($this->logger instanceof LoggerInterface) {
-                            $this->logger->warning("Exception is caught with message {$e->getMessage()}", [
-                                'exception' => $e,
-                            ]);
+                        if ($this->logger) {
+                            $this->logger->error($this->getLogExceptionMessage(), ['exception' => $e]);
+                        }
+
+                        $exception_message = $this->action_exception_message;
+
+                        if (strpos($exception_message, '{message}') !== false) {
+                            $exception_message = str_replace('{message}', $e->getMessage(), $exception_message);
                         }
 
-                        return $this->getResultEncoder()->encode($e, $request, $response);
+                        return $this->getResultEncoder()->encode(new RuntimeException($exception_message, 0, $e), $request, $response);
                     }
                 }
             } else {

src/ControllerInterface.php

@@ -9,6 +9,7 @@
 namespace ActiveCollab\Controller;
 
 use ActiveCollab\Controller\ResultEncoder\ResultEncoderInterface;
+use Psr\Log\LoggerInterface;
 
 /**
  * @package ActiveCollab\Controller
@@ -30,6 +31,55 @@ public function getResultEncoder();
      */
     public function &setResultEncoder(ResultEncoderInterface $result_encoder);
 
+    /**
+     * Return logger.
+     *
+     * @return LoggerInterface|null
+     */
+    public function getLogger();
+
+    /**
+     * Set logger.
+     *
+     * @param  LoggerInterface|null $logger
+     * @return $this
+     */
+    public function &setLogger(LoggerInterface $logger = null);
+
+    /**
+     * Return message that is returned as 500 error when action breaks due to an exception.
+     *
+     * @return string
+     */
+    public function getClientFacingExceptionMessage();
+
+    /**
+     * Set message that is returned as 500 error when action breaks due to exception.
+     *
+     * If you wish to include actual exception's message, add {message} to the test. Example:
+     *
+     * $controller->setActionExceptionMessage('Failed because {message}');
+     *
+     * @param  string $message
+     * @return $this
+     */
+    public function &setClientFacingExceptionMessage($message);
+
+    /**
+     * Return message that will be logged if contraoller action fails due to an exception.
+     *
+     * @return string
+     */
+    public function getLogExceptionMessage();
+
+    /**
+     * Set message that will be logged if contraoller action fails due to an exception.
+     *
+     * @param  string $message
+     * @return $this
+     */
+    public function &setLogExceptionMessage($message);
+
     /**
      * Return controller name, without namespace.
      *