Erros & Exceções

Os aplicativos CakePHP vêm com a configuração de tratamento de erros e exceções para você. Os erros do PHP são capturados e exibidos ou registrados. Exceções não capturadas são renderizadas em páginas de erro automaticamente.

Configurações de Erro & Exceções

A configuração do erro é feita no arquivo config/app.php do seu aplicativo. Por padrão, o CakePHP usa Cake\Error\ErrorHandler para lidar com erros e exceções do PHP por padrão. A configuração de erro permite personalizar o tratamento de erros para o seu aplicativo. As seguintes opções são suportadas:

  • errorLevel - int - O nível de erros que você está interessado em capturar. Use as constantes de erro embutidas no PHP e máscaras de bits para selecionar o nível de erro no qual você precisa. Você pode configurá-lo como E_ALL ^ E_USER_DEPRECATED para desativar os avisos de depreciação.
  • trace - bool - Inclua rastreamentos de pilha para erros nos arquivos de log. Rastreamentos de pilha serão incluídos no log após cada erro. Isso é útil para descobrir onde/quando os erros estão sendo gerados
  • exceptionRenderer - string - A classe responsável por renderizar exceções não capturadas. Se você escolher uma classe personalizada, coloque o arquivo dessa classe em src/Error. Esta classe precisa implementar o método render().
  • log - bool - Quando true, as exceções + seus rastreamentos de pilha serão registrados em Cake\Log\Log
  • skipLog - array - Uma matriz de nomes de classes de exceção que não devem ser registrados. Isso é útil para remover NotFoundExceptions ou outras mensagens de log comuns, mas desinteressantes.
  • extraFatalErrorMemory - int - Defina como o número de megabytes para aumentar o limite de memória quando um erro fatal for encontrado. Isso permite que o espaço sobrando complete o registro ou o tratamento de erros.

Por padrão, os erros do PHP são exibidos quando debug é true e registrados quando o debug é false. O manipulador de erro fatal será chamado independente da configuração do nível debug ou errorLevel, mas o resultado será diferente com base no nível de debug. O comportamento padrão para erros fatais é mostrar uma página para o erro interno do servidor (debug desativado) ou uma página com a mensagem, arquivo e linha (debug ativada).

Nota

Se você usar um manipulador de erros personalizado, as opções suportadas dependerão do seu manipulador.

class ExceptionRenderer(Exception $exception)

Alterando o tratamento de exceções

O tratamento de exceções oferece várias maneiras de personalizar como as exceções são tratadas. Cada abordagem fornece diferentes quantidades de controle sobre o processo de tratamento de exceções.

  1. Customize o template de error Isso permite alterar os modelos de exibição renderizados como faria com qualquer outro modelo em seu aplicativo.
  2. Customize o ErrorController Isso permite que você controle como as páginas de exceção são renderizadas.
  3. Customize o ExceptionRenderer Isso permite que você controle como as páginas de exceção e o log são executados.
  4. Crie e registre seu próprio manipulador de erros Isso fornece controle total sobre como os erros e exceções são tratados, registrados e renderizados.

Customizando Templates de Erro

O manipulador de erros padrão renderiza todas as exceções não capturadas que seu aplicativo gera com a ajuda de Cake\Error\ExceptionRenderer e o ErrorController do seu aplicativo.

As visualizações da página de erro estão localizadas em src/Template/Error/. Por padrão, todos os erros 4xx usam o modelo error400.ctp e todos os erros 5xx usam o error500.ctp. Seus modelos de erro terão as seguintes variáveis disponíveis:

  • message A mensagem da exceção.
  • code O código da exceção.
  • url A URL requisitada.
  • error O objeto da exceção.

No modo de depuração, se o erro estender Cake\Core\Exception\Exception, os dados retornados por getAttributes() serão expostos como variáveis de exibição também.

Nota

Você precisará definir debug para false, para ver seus modelos error404 e error500. No modo de depuração, você verá a página de erro de desenvolvimento do CakePHP.

Personalizar o layout da página de erro

By default error templates use src/Template/Layout/error.ctp for a layout. You can use the layout property to pick a different layout:

// inside src/Template/Error/error400.ctp
$this->layout = 'my_error';

The above would use src/Template/Layout/my_error.ctp as the layout for your error pages.

Many exceptions raised by CakePHP will render specific view templates in debug mode. With debug turned off all exceptions raised by CakePHP will use either error400.ctp or error500.ctp based on their status code.

Customize the ErrorController

The App\Controller\ErrorController class is used by CakePHP’s exception rendering to render the error page view and receives all the standard request life-cycle events. By modifying this class you can control which components are used and which templates are rendered.

If your application uses routing-prefixes you can create custom error controllers for each routing prefix. For example, if you had an admin prefix. You could create the following class:

namespace App\Controller\Admin;

use App\Controller\AppController;

class ErrorController extends AppController
{
    /**
     * Initialization hook method.
     *
     * @return void
     */
    public function initialize()
    {
        $this->loadComponent('RequestHandler');
    }

    /**
     * beforeRender callback.
     *
     * @param \Cake\Event\Event $event Event.
     * @return void
     */
    public function beforeRender(Event $event)
    {
        $this->viewBuilder()->setTemplatePath('Error');
    }
}

This controller would only be used when an error is encountered in a prefixed controller, and allows you to define prefix specific logic/templates as needed.

Novo na versão 3.7.0: Prefixed error controllers were added.

Change the ExceptionRenderer

If you want to control the entire exception rendering and logging process you can use the Error.exceptionRenderer option in config/app.php to choose a class that will render exception pages. Changing the ExceptionRenderer is useful when you want to provide custom error pages for application specific exception classes.

Your custom exception renderer class should be placed in src/Error. Let’s assume our application uses App\Exception\MissingWidgetException to indicate a missing widget. We could create an exception renderer that renders specific error pages when this error is handled:

// In src/Error/AppExceptionRenderer.php
namespace App\Error;

use Cake\Error\ExceptionRenderer;

class AppExceptionRenderer extends ExceptionRenderer
{
    public function missingWidget($error)
    {
        $response = $this->controller->response;

        return $response->withStringBody('Oops that widget is missing.');
    }
}

// In config/app.php
'Error' => [
    'exceptionRenderer' => 'App\Error\AppExceptionRenderer',
    // ...
],
// ...

The above would handle our MissingWidgetException, and allow us to provide custom display/handling logic for those application exceptions.

Exception rendering methods receive the handled exception as an argument, and should return a Response object. You can also implement methods to add additional logic when handling CakePHP errors:

// In src/Error/AppExceptionRenderer.php
namespace App\Error;

use Cake\Error\ExceptionRenderer;

class AppExceptionRenderer extends ExceptionRenderer
{
    public function notFound($error)
    {
        // Do something with NotFoundException objects.
    }
}

Changing the ErrorController Class

The exception renderer dictates which controller is used for exception rendering. If you want to change which controller is used to render exceptions, override the _getController() method in your exception renderer:

// in src/Error/AppExceptionRenderer
namespace App\Error;

use App\Controller\SuperCustomErrorController;
use Cake\Error\ExceptionRenderer;

class AppExceptionRenderer extends ExceptionRenderer
{
    protected function _getController()
    {
        return new SuperCustomErrorController();
    }
}

// in config/app.php
'Error' => [
    'exceptionRenderer' => 'App\Error\AppExceptionRenderer',
    // ...
],
// ...

Creating your Own Error Handler

By replacing the error handler you can customize the entire error & exception handling process. By extending Cake\Error\BaseErrorHandler you can customize display logic more simply. As an example, we could build a class called AppError to handle our errors:

// In config/bootstrap.php
use App\Error\AppError;

$errorHandler = new AppError();
$errorHandler->register();

// In src/Error/AppError.php
namespace App\Error;

use Cake\Error\BaseErrorHandler;

class AppError extends BaseErrorHandler
{
    public function _displayError($error, $debug)
    {
        echo 'There has been an error!';
    }

    public function _displayException($exception)
    {
        echo 'There has been an exception!';
    }
}

The BaseErrorHandler defines two abstract methods. _displayError() is used when errors are triggered. The _displayException() method is called when there is an uncaught exception.

Changing Fatal Error Behavior

Error handlers convert fatal errors into exceptions and re-use the exception handling logic to render an error page. If you do not want to show the standard error page, you can override it:

// In src/Error/AppError.php
namespace App\Error;

use Cake\Error\BaseErrorHandler;

class AppError extends BaseErrorHandler
{
    // Other methods.

    public function handleFatalError($code, $description, $file, $line)
    {
        echo 'A fatal error has happened';
    }
}

Creating your own Application Exceptions

You can create your own application exceptions using any of the built in SPL exceptions, Exception itself, or Cake\Core\Exception\Exception. If your application contained the following exception:

use Cake\Core\Exception\Exception;

class MissingWidgetException extends Exception
{
}

You could provide nice development errors, by creating src/Template/Error/missing_widget.ctp. When in production mode, the above error would be treated as a 500 error and use the error500 template.

If your exceptions have a code between 400 and 506 the exception code will be used as the HTTP response code.

The constructor for Cake\Core\Exception\Exception allows you to pass in additional data. This additional data is interpolated into the the _messageTemplate. This allows you to create data rich exceptions, that provide more context around your errors:

use Cake\Core\Exception\Exception;

class MissingWidgetException extends Exception
{
    // Context data is interpolated into this format string.
    protected $_messageTemplate = 'Seems that %s is missing.';

    // You can set a default exception code as well.
    protected $_defaultCode = 404;
}

throw new MissingWidgetException(['widget' => 'Pointy']);

When rendered, this your view template would have a $widget variable set. If you cast the exception as a string or use its getMessage() method you will get Seems that Pointy is missing..

Logging Exceptions

Using the built-in exception handling, you can log all the exceptions that are dealt with by ErrorHandler by setting the log option to true in your config/app.php. Enabling this will log every exception to Cake\Log\Log and the configured loggers.

Nota

If you are using a custom exception handler this setting will have no effect. Unless you reference it inside your implementation.

Built in Exceptions for CakePHP

HTTP Exceptions

There are several built-in exceptions inside CakePHP, outside of the internal framework exceptions, there are several exceptions for HTTP methods

exception Cake\Http\Exception\BadRequestException

Used for doing 400 Bad Request error.

exception Cake\Http\Exception\UnauthorizedException

Used for doing a 401 Unauthorized error.

exception Cake\Http\Exception\ForbiddenException

Used for doing a 403 Forbidden error.

Novo na versão 3.1: InvalidCsrfTokenException has been added.

exception Cake\Http\Exception\InvalidCsrfTokenException

Used for doing a 403 error caused by an invalid CSRF token.

exception Cake\Http\Exception\NotFoundException

Used for doing a 404 Not found error.

exception Cake\Http\Exception\MethodNotAllowedException

Used for doing a 405 Method Not Allowed error.

exception Cake\Http\Exception\NotAcceptableException

Used for doing a 406 Not Acceptable error.

Novo na versão 3.1.7: NotAcceptableException has been added.

exception Cake\Http\Exception\ConflictException

Used for doing a 409 Conflict error.

Novo na versão 3.1.7: ConflictException has been added.

exception Cake\Http\Exception\GoneException

Used for doing a 410 Gone error.

Novo na versão 3.1.7: GoneException has been added.

For more details on HTTP 4xx error status codes see RFC 2616#section-10.4.

exception Cake\Http\Exception\InternalErrorException

Used for doing a 500 Internal Server Error.

exception Cake\Http\Exception\NotImplementedException

Used for doing a 501 Not Implemented Errors.

exception Cake\Http\Exception\ServiceUnavailableException

Used for doing a 503 Service Unavailable error.

Novo na versão 3.1.7: Service Unavailable has been added.

For more details on HTTP 5xx error status codes see RFC 2616#section-10.5.

You can throw these exceptions from your controllers to indicate failure states, or HTTP errors. An example use of the HTTP exceptions could be rendering 404 pages for items that have not been found:

// Prior to 3.6 use Cake\Network\Exception\NotFoundException
use Cake\Http\Exception\NotFoundException;

public function view($id = null)
{
    $article = $this->Articles->findById($id)->first();
    if (empty($article)) {
        throw new NotFoundException(__('Article not found'));
    }
    $this->set('article', $article);
    $this->set('_serialize', ['article']);
}

By using exceptions for HTTP errors, you can keep your code both clean, and give RESTful responses to client applications and users.

Using HTTP Exceptions in your Controllers

You can throw any of the HTTP related exceptions from your controller actions to indicate failure states. For example:

use Cake\Network\Exception\NotFoundException;

public function view($id = null)
{
    $article = $this->Articles->findById($id)->first();
    if (empty($article)) {
        throw new NotFoundException(__('Article not found'));
    }
    $this->set('article', 'article');
    $this->set('_serialize', ['article']);
}

The above would cause the configured exception handler to catch and process the NotFoundException. By default this will create an error page, and log the exception.

Other Built In Exceptions

In addition, CakePHP uses the following exceptions:

exception Cake\View\Exception\MissingViewException

The chosen view class could not be found.

exception Cake\View\Exception\MissingTemplateException

The chosen template file could not be found.

exception Cake\View\Exception\MissingLayoutException

The chosen layout could not be found.

exception Cake\View\Exception\MissingHelperException

The chosen helper could not be found.

exception Cake\View\Exception\MissingElementException

The chosen element file could not be found.

exception Cake\View\Exception\MissingCellException

The chosen cell class could not be found.

exception Cake\View\Exception\MissingCellViewException

The chosen cell view file could not be found.

exception Cake\Controller\Exception\MissingComponentException

A configured component could not be found.

exception Cake\Controller\Exception\MissingActionException

The requested controller action could not be found.

exception Cake\Controller\Exception\PrivateActionException

Accessing private/protected/_ prefixed actions.

exception Cake\Console\Exception\ConsoleException

A console library class encounter an error.

exception Cake\Console\Exception\MissingTaskException

A configured task could not found.

exception Cake\Console\Exception\MissingShellException

The shell class could not be found.

exception Cake\Console\Exception\MissingShellMethodException

The chosen shell class has no method of that name.

exception Cake\Database\Exception\MissingConnectionException

A model’s connection is missing.

exception Cake\Database\Exception\MissingDriverException

A database driver could not be found.

exception Cake\Database\Exception\MissingExtensionException

A PHP extension is missing for the database driver.

exception Cake\ORM\Exception\MissingTableException

A model’s table could not be found.

exception Cake\ORM\Exception\MissingEntityException

A model’s entity could not be found.

exception Cake\ORM\Exception\MissingBehaviorException

A model’s behavior could not be found.

exception Cake\ORM\Exception\PersistenceFailedException

An entity couldn’t be saved/deleted while using Cake\ORM\Table::saveOrFail() or Cake\ORM\Table::deleteOrFail().

Novo na versão 3.4.1: PersistenceFailedException has been added.

exception Cake\Datasource\Exception\RecordNotFoundException

The requested record could not be found. This will also set HTTP response headers to 404.

exception Cake\Routing\Exception\MissingControllerException

The requested controller could not be found.

exception Cake\Routing\Exception\MissingRouteException

The requested URL cannot be reverse routed or cannot be parsed.

exception Cake\Routing\Exception\MissingDispatcherFilterException

The dispatcher filter could not be found.

exception Cake\Core\Exception\Exception

Base exception class in CakePHP. All framework layer exceptions thrown by CakePHP will extend this class.

These exception classes all extend Exception. By extending Exception, you can create your own ‘framework’ errors.

Cake\Core\Exception\Exception::responseHeader($header = null, $value = null)

See Cake\Network\Request::header()

All Http and Cake exceptions extend the Exception class, which has a method to add headers to the response. For instance when throwing a 405 MethodNotAllowedException the rfc2616 says:

"The response MUST include an Allow header containing a list of valid
methods for the requested resource."