Slim supports PSR-7 interfaces for its Request and Response objects. This makes Slim flexible because it can use any PSR-7 implementation. For example, a Slim application route does not have to return an instance of \Slim\Http\Response
. It could, for example, return an instance of \GuzzleHttp\Psr7\CachingStream
or any instance returned by the \GuzzleHttp\Psr7\stream_for()
function.
Slim provides its own PSR-7 implementation so that it works out of the box. However, you are free to replace Slim’s default PSR-7 objects with a third-party implementation. Just override the application container’s request
and response
services so they return an instance of \Psr\Http\Message\ServerRequestInterface
and \Psr\Http\Message\ResponseInterface
, respectively.
Value objects
Slim’s Request and Response objects are immutable value objects. They can be “changed” only by requesting a cloned version that has updated property values. Value objects have a nominal overhead because they must be cloned when their properties are updated. This overhead does not affect performance in any meaningful way.
You can request a copy of a value object by invoking any of its PSR-7 interface methods (these methods typically have a with
prefix). For example, a PSR-7 Response object has a withHeader($name, $value)
method that returns a cloned value object with the new HTTP header.
<?php
$app = new \Slim\App;
$app->get('/foo', function ($req, $res, $args) {
return $res->withHeader(
'Content-Type',
'application/json'
);
});
$app->run();
The PSR-7 interface provides these methods to transform Request and Response objects:
withProtocolVersion($version)
withHeader($name, $value)
withAddedHeader($name, $value)
withoutHeader($name)
withBody(StreamInterface $body)
The PSR-7 interface provides these methods to transform Request objects:
withMethod($method)
withUri(UriInterface $uri, $preserveHost = false)
withCookieParams(array $cookies)
withQueryParams(array $query)
withUploadedFiles(array $uploadedFiles)
withParsedBody($data)
withAttribute($name, $value)
withoutAttribute($name)
The PSR-7 interface provides these methods to transform Response objects:
withStatus($code, $reasonPhrase = '')
Refer to the PSR-7 documentation for more information about these methods.
via https://www.slimframework.com/docs/v3/concepts/value-objects.html