Dummy client and server middleware for PSR-7 requests. Works both as PSR-15 and double pass middleware.

The dummy services work as null objects / passthrough, preventing the use of if's.

composer require jasny/dummy-middleware

Server middleware can be used all passthrough of PSR-7 server requests.

The middleware implements the PSR-15 MiddlewareInterface. As PSR standard many new libraries support this type of middleware, for example Zend Stratigility.

use Jasny\Dummy\ServerMiddleware;
use Zend\Stratigility\MiddlewarePipe;
use Zend\Diactoros\ResponseFactory;

$middleware = new ServerMiddleware();

$app = new MiddlewarePipe();
$app->pipe($middleware);

Many PHP libraries support double pass middleware. These are callables with the following signature;

fn(ServerRequestInterface $request, ResponseInterface $response, callable $next): ResponseInterface

To get a callback to be used by libraries as Jasny Router and Relay, use the asDoublePass() method.

use Jasny\Dummy\ServerMiddleware;
use Relay\RelayBuilder;

$middleware = new ServerMiddleware();

$relayBuilder = new RelayBuilder($resolver);
$relay = $relayBuilder->newInstance([
    $middleware->asDoublePass(),
]);

$response = $relay($request, $baseResponse);

Client middleware can be used for PSR-7 compatible HTTP clients like Guzzle and HTTPlug.

The client middleware can be used by any client that does support double pass middleware. Such middleware are callables with the following signature;

fn(RequestInterface $request, ResponseInterface $response, callable $next): ResponseInterface

Most HTTP clients do not support double pass middleware, but a type of single pass instead. However more general purpose PSR-7 middleware libraries, like Relay, do support double pass.

use Relay\RelayBuilder;
use Jasny\Dummy\ClientMiddleware;

$middleware = new ClientMiddleware();

$relayBuilder = new RelayBuilder($resolver);
$relay = $relayBuilder->newInstance([
    $middleware->asDoublePass(),
]);

$response = $relay($request, $baseResponse);

The client middleware does not conform to PSR-15 (single pass) as that is intended for server requests only.

Guzzle is the most popular HTTP Client for PHP. The middleware has a forGuzzle() method that creates a callback which can be used as Guzzle middleware.

use GuzzleHttp\HandlerStack;
use GuzzleHttp\Client;
use Jasny\Dummy\ClientMiddleware;

$middleware = new ClientMiddleware();

$stack = new HandlerStack();
$stack->push($middleware->forGuzzle());

$client = new Client(['handler' => $stack]);

HTTPlug is the HTTP client of PHP-HTTP. It allows you to write reusable libraries and applications that need an HTTP client without binding to a specific implementation.

The forHttplug() method for the middleware creates an object that can be used as HTTPlug plugin.

use Http\Discovery\HttpClientDiscovery;
use Http\Client\Common\PluginClient;
use Jasny\Dummy\ClientMiddleware;

$middleware = new ClientMiddleware();

$pluginClient = new PluginClient(
    HttpClientDiscovery::find(),
    [
        $middleware->forHttplug(),
    ]
);