PSR-7 and PSR-15 are PHP standards for representing HTTP messages and server request handling. PSR-7 defines interfaces for HTTP messages like requests and responses, while PSR-15 defines interfaces for request handlers and middleware. These standards provide a common way for PHP libraries to interact with HTTP messages and requests, improving interoperability. They also allow applications to be built in a way that is compatible with evolving PHP frameworks and tools. Adopting these PSRs helps create a solid foundation for building HTTP applications and middleware in PHP.

1. PSR-7 and PSR-15
Why can't you ignore them?

2. github/@sergiors
twitter/@serg1ors

3. The PHP Framework
Interop Group

4. PHP Standard
Recommendation

5. HTTP Protocol

6. https://symfony.com/doc/current/introduction/http_fundamentals.html

7. HTTP messages are the
foundation of web
development

8. GET https://www.php-fig.org/psr/psr-7/ HTTP/1.1
Accept: text/html,application/xhtml+xml,application/
xml;q=0.9,*/*;q=0.8
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.5
Cache-Control: no-cache
Connection: keep-alive
Host: www.php-fig.org
Pragma: no-cache
User-Agent: Mozilla/5.0 Gecko/20100101 Firefox/59.0
https://www.w3.org/Protocols/rfc2616/rfc2616-sec5.html
Every HTTP request message has a
specific form

9. HTTP/1.1 200 OK
Cache-Control: max-age=300
Content-Encoding: br
Content-Type: text/html
Date: Thu, 19 Apr 2018 23:32:18 GMT
Etag: W/"5acdc656-1ab41"
Expires: Wed, 11 Apr 2018 09:14:49 GMT
Last-Modified: Wed, 11 Apr 2018 08:24:54 GMT
Strict-Transport-Security: max-age=0
Vary: Accept-Encoding
X-Debug-Info: eyJyZXRyaWVzIjowfQ==
Transfer-Encoding: chunked
https://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html#sec6

10. Common Gateway
Interface (CGI)

11. PHP’s Server APIs (SAPI)

12. https://www.php-fig.org/psr/psr-7/
PSR-7: HTTP message
interfaces

13. PSR-7 describes common interfaces for
representing HTTP messages as
described in RFC 7230 and
RFC 7231, and URIs for use with HTTP
messages as described in RFC 3986.
https://www.php-fig.org/psr/psr-7/

14. But for what?

15. HTTP’s abstraction

16. Allow you create your own
implementation

17. PSR-7 tells you how to
build http application

18. Manage memory

19. $ composer require psr/http-message

20. use PsrHttpMessageMessageInterface;
use PsrHttpMessageRequestInterface;
use PsrHttpMessageResponseInterface;
use PsrHttpMessageServerRequestInterface;
use PsrHttpMessageStreamInterface;
use PsrHttpMessageUploadedFileInterface;
use PsrHttpMessageUriInterface;
PSR-7 Interfaces
https://www.php-fig.org/psr/psr-7/

21. https://www.php-fig.org/psr/psr-7/
use PsrHttpMessageRequestInterface;
use PsrHttpMessageServerRequestInterface;
use PsrHttpMessageResponseInterface;

22. https://www.php-fig.org/psr/psr-7/
use PsrHttpMessageMessageInterface;
use PsrHttpMessageUriInterface;

23. use PsrHttpMessageStreamInterface;
https://www.php-fig.org/psr/psr-7/

24. $body = (new Stream)->write(
json_encode([
'foo' => 'bar',
]
));

25. use PsrHttpMessageStreamInterface;
class Image implements StreamInterface
{
/* etc. */
}
$image = new Image(__DIR__ . '/cats.png');

26. $filename = sprintf(
'%s.%s',
create_uuid(),
pathinfo(
$file0->getClientFilename(),
PATHINFO_EXTENSION
)
);
$file0->moveTo(DATA_DIR . '/' . $filename);
$stream = new Psr7StreamWrapper($file1->getStream());
stream_copy_to_stream($stream, $s3wrapper);

27. use PsrHttpMessageUploadedFileInterface;
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

28. array(
'files' => array(
'name' => array(
0 => 'file0.txt',
1 => 'file1.html',
),
'type' => array(
0 => 'text/plain',
1 => 'text/html',
),
/* etc. */
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

29. array(
'files' => array(
0 => array(
'name' => 'file0.txt',
'type' => 'text/plain',
/* etc. */
),
1 => array(
'name' => 'file1.html',
'type' => 'text/html',
/* etc. */
),
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

30. array(
'avatar' => array(
'tmp_name' => 'phpUxcOty',
'name' => 'my-avatar.png',
'size' => 90996,
'type' => 'image/png',
'error' => 0,
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

31. array(
'avatar' => array(
'tmp_name' => 'phpUxcOty',
'name' => 'my-avatar.png',
'size' => 90996,
'type' => 'image/png',
'error' => 0,
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

32. array(
'avatar' => /* UploadedFileInterface instance */
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

33. array(
'files' => array(
0 => /* UploadedFileInterface instance */,
1 => /* UploadedFileInterface instance */,
2 => /* UploadedFileInterface instance */,
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

34. array(
'files' => array(
'name' => array(
0 => 'file0.txt',
1 => 'file1.html',
),
'type' => array(
0 => 'text/plain',
1 => 'text/html',
),
/* etc. */
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

35. array(
'files' => array(
0 => array(
'name' => 'file0.txt',
'type' => 'text/plain',
/* etc. */
),
1 => array(
'name' => 'file1.html',
'type' => 'text/html',
/* etc. */
),
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

36. array(
'avatar' => array(
'tmp_name' => 'phpUxcOty',
'name' => 'my-avatar.png',
'size' => 90996,
'type' => 'image/png',
'error' => 0,
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

37. array(
'avatar' => array(
'tmp_name' => 'phpUxcOty',
'name' => 'my-avatar.png',
'size' => 90996,
'type' => 'image/png',
'error' => 0,
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

38. array(
'avatar' => /* UploadedFileInterface instance */
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

39. array(
'files' => array(
0 => /* UploadedFileInterface instance */,
1 => /* UploadedFileInterface instance */,
2 => /* UploadedFileInterface instance */,
),
)
https://www.php-fig.org/psr/psr-7/#16-uploaded-files

40. Final conclusion

41. Solid API for HTTP
representation

42. Compatible with evolution
PHP ecosystem

43. https://www.php-fig.org/psr/psr-15/
PSR-15: HTTP Server
Request Handlers

44. PSR-15 describes common interfaces
for HTTP server request handlers and
HTTP server middleware components
that use HTTP messages as described
by PSR-7 or subsequent replacement
PSRs.
https://www.php-fig.org/psr/psr-15/

45. Pipeline is a series of processing stages
$ ps aux | grep firefox | grep -v grep | awk '{print $2}'

46. Middleware

48. Delegation

49. $ composer require psr/http-server-middleware

50. use PsrHttpServerRequestHandlerInterface;
use PsrHttpServerMiddlewareInterface;
PSR-15: HTTP Server Request Handlers
https://www.php-fig.org/psr/psr-15/

51. use PsrHttpServerRequestHandlerInterface;
https://www.php-fig.org/psr/psr-15/#21-psrhttpserverrequesthandlerinterface

52. use PsrHttpServerMiddlewareInterface;
https://www.php-fig.org/psr/psr-15/#22-psrhttpservermiddlewareinterface

53. $app->pipe(new DoctrineOrmMiddleware(/* etc. */));
$app->get('/api/users/{id}', [
new AuthorizationMiddleware(/* etc. */),
function (ServerRequestInterface $req) {
try {
return new TextResponse(
(string) $req
->getAttribute('orm')
->getRepository(User::class)
->findOneById(
$req->getAttribute('id', false)
)
);
} catch (Throwable $e) {}
throw new NotFoundException;
},
]);

54. public function process(
ServerRequestInterface $request,
RequestHandlerInterface $handler
): ResponseInterface {
$result = $this->router->match($request);
$request = $request
->withAttribute(RouteResult::class, $result);
if ($result->isSuccess()) {
foreach ($result->getMatchedParams() as $param => $value) {
$request = $request->withAttribute($param, $value);
}
}
return $handler->handle($request);
}

55. public function process(
ServerRequestInterface $request,
RequestHandlerInterface $handler
): ResponseInterface {
$result = $request
->getAttribute(RouteResult::class, false);
if ($result instanceof RouteResult) {
$this->helper->setRouteResult($result);
}
return $handler->handle($request);
}

56. https://github.com/phly/psr7examples
https://docs.zendframework.com/zend-stratigility/
https://docs.zendframework.com/zend-diactoros/
https://github.com/middlewares

57. https://symfony.com/doc/current/introduction/http_fundamentals.html

58. PSR-7 and PSR-15 is real, these
PSRs affects how the library
for http is written in PHP

59. PSRs is a historical landmark
for PHP ecosystem

60. General purpose

61. “I would advise students to pay more
attention to the fundamental ideas rather
than the latest technology. The technology
will be out-of-date before they graduate.
Fundamental ideas never get out of date.”
–David Lorge Parnas
https://www.sigsoft.org/SEN/parnas.html

62. Thank you!
twitter.com/serg1ors
github.com/sergiors