middlewares/error-handler

Middleware to handle http errors

middlewares/error-handler

![Software License][ico-license] ![Total Downloads][ico-downloads], _(*1)

Middleware to catch and format errors encountered while handling the request., _(*2)

Requirements

• PHP >= 7.2
• A PSR-7 http library
• A PSR-15 middleware dispatcher

Installation

This package is installable and autoloadable via Composer as middlewares/error-handler., _(*3)

composer require middlewares/error-handler

Example

use Middlewares\ErrorFormatter;
use Middlewares\ErrorHandler;
use Middlewares\Utils\Dispatcher;

// Create a new ErrorHandler instance
// Any number of formatters can be added. One will be picked based on the Accept
// header of the request. If no formatter matches, the first formatter in the array
// will be used.
$errorHandler = new ErrorHandler([
    new ErrorFormatter\HtmlFormatter(),
    new ErrorFormatter\ImageFormatter(),
    new ErrorFormatter\JsonFormatter(),
    new ErrorFormatter\PlainFormatter(),
    new ErrorFormatter\SvgFormatter(),
    new ErrorFormatter\XmlFormatter(),
]);

// ErrorHandler should always be the first middleware in the stack!
$dispatcher = new Dispatcher([
    $errorHandler,
    // ...
    function ($request) {
        throw HttpErrorException::create(404);
    }
]);

$request = $serverRequestFactory->createServerRequest('GET', '/');
$response = $dispatcher->dispatch($request);

Usage

Add the formatters to be used (instances of Middlewares\ErrorFormatter\FormatterInterface). If no formatters are provided, use all available., _(*4)

$errorHandler = new ErrorHandler([
    new ErrorFormatter\HtmlFormatter(),
    new ErrorFormatter\JsonFormatter()
]);

Note: If no formatter is found, the first value of the array will be used. In the example above, HtmlFormatter., _(*5)

How to log the error and delegate the formatting to the middleware

Please note that the following snippet must go even before error-hander's middleware, which usually goes first., _(*6)

public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
{
    try {
        return $handler->handle($request);
    } catch (Throwable $exception) {
        $this->logger->critical('Uncaught {error}', [
            'error' => $exception->getMessage(),
            'exception' => $exception, // If you use Monolog, this is correct
        ]);

        // leave it for the middleware
        throw $exception;
    }
}

How to use a custom response for Production

This snippet might come handy when you want to customize your response in production., _(*7)

class PrettyPage implements StreamFactoryInterface
{
    public function createStream(string $content = ''): StreamInterface
    {
        return Factory::createStream('<strong>Pretty page</strong>');
    }

    public function createStreamFromFile(string $filename, string $mode = 'r'): StreamInterface
    {
        // This is safe as the Middleware only uses createStream()
        throw new Exception('Not implemented');
    }

    public function createStreamFromResource($resource): StreamInterface
    {
        // This is safe as the Middleware only uses createStream()
        throw new Exception('Not implemented');
    }
}


$errorHandler = new ErrorHandler([
    new HtmlFormatter(
        null,
        new PrettyPage,
    ),
]);

Please see CHANGELOG for more information about recent changes and CONTRIBUTING for contributing details., _(*8)

The MIT License (MIT). Please see LICENSE for more information., _(*9)