Hello, PSR-7. (phpDay 2015)

PSR-7 HTTP Message Interface has been kicking around in one form or another since March of 2012. Get a brief history of how PSR-7 evolved from its humble beginnings as a simple HTTP client interface to the game-changing PHP-FIG proposal we have today. Learn how to work with the HTTP Message Interfaces and how they will be used by frameworks in the not to distant future. Find out what it will mean to have a healthy ecosystem of PHP software all speak HTTP the same way. Say hello to your new best friend in PHP, PSR-7.

Transcript

1. Hello, PSR-7.
2. PSR-7 HTTP Message Interface
3. The Problem Server-Side Edition
4. My background (It is relevant, I promise!)
5. PHP ~2005
6. Spring Framework ~2008
7. class halo_HttpRequest { public function __construct( $method, array $queryParams = null, array $postParams = null, array $fileData = null, array $env = null, $body = null ) { // ... } }
8. class halo_DispatcherUtil { public static function MAKE_HTTP_REQUEST() { return new halo_HttpRequest( $_SERVER['REQUEST_METHOD'], $_GET, $_POST, $_FILES, $_SERVER ); } }
9. namespace Symfony\Component\HttpFoundation; class Request { public function __construct( array $query = array(), array $request = array(), array $attributes = array(), array $cookies = array(), array $files = array(), array $server = array(), $content = null ) { // ... } }
10. namespace Symfony\Component\HttpFoundation; class Request { public static function createFromGlobals() { return self::createRequestFromFactory( $_GET, $_POST, array(), $_COOKIE, $_FILES, $server ); } }
11. namespace Zend\Http\PhpEnvironment; class Request extends \Zend\Http\Request { public function __construct() { $this->setEnv(new Parameters($_ENV)); if ($_GET) { $this->setQuery(new Parameters($_GET)); } if ($_POST) { $this->setPost(new Parameters($_POST)); } if ($_COOKIE) { $this->setCookies(new Parameters($_COOKIE)); } if ($_FILES) { $files = $this->mapPhpFiles(); $this->setFiles(new Parameters($files)); } $this->setServer(new Parameters($_SERVER)); } }
12. namespace Aura\Web; class WebFactory { public function newRequest() { return new Request( $this->newRequestClient(), $this->newRequestContent(), $this->newRequestGlobals(), $this->newRequestHeaders(), $this->newRequestMethod(), $this->newRequestParams(), $this->newRequestUrl() ); } public function newRequestGlobals() { return new Request\Globals( $this->newRequestCookies(), $this->newRequestEnv(), $this->newRequestFiles(), $this->newRequestPost(), $this->newRequestQuery(), $this->newRequestServer() ); } }
13. All define similar Responses
14. Abstractions over SAPI
15. Impact on Ecosystem
16. Symfony 2 HttpFoundation + HttpKernel
18. What if we could share code between these applications and frameworks at the HTTP level? — Igor, Beau, and Christoph
19. Stack PHP Conventions for writing framework agnostic* middleware stackphp.com
20. Slowly and quietly adopted by parts of the Symfony ecosystem
21. The Problem Client-Side Edition
22. Guzzle, Buzz, Requests
24. The Problem for both server-side and client-side: HTTP Messages abstraction should be a commodity <message line> Header: value Another-Header: value Message body
25. History of PSR-7
26. PHP-FIG PHP Framework Interoperability Group
27. March 24th, 2012 HTTP Client interface Benjamin Eberlei
28. $client = create_http_client(); // implementation specific $response = $client->request('GET', 'http://www.php.net'); if ($response->getStatusCode() == 200) { $content = $response->getContent(); } $response = $client->request('GET', 'http://api/returning.json'); if ($response->getContentType() == 'application/json') { $json = json_decode($response->getContent()); }
29. December 31st, 2012 HTTP Message Chris Wilkinson
30. There was a proposal to create a HTTP client interface earlier this year. As was noted at the time, the core HTTP message representation part (ie the request/response objects) is probably of more importance: it's used by both HTTP clients and frameworks. — Chris Wilkinson
31. interface MessageInterface { public function __toString(); public function getStartLine(); public function getProtocolVersion(); public function setProtocolVersion($protocolVersion); public function getHeader($header); public function getHeaders(); public function hasHeader($header); public function setHeader($header, $value); public function setHeaders(array $headers); public function addHeaders(array $headers); public function getBody(); public function setBody($body); }
32. interface RequestInterface extends MessageInterface { public function __construct( $method, $url, $protocolVersion = '1.1' ); public function getResponse(); public function setResponse(ResponseInterface $response); public function getMethod(); public function setMethod($method); public function getUrl(); public function setUrl($url); }
33. interface ResponseInterface extends MessageInterface { public function __construct( $statusCode, $reasonPhrase = null, $protocolVersion = '1.1' ); public function getRequest(); public function setRequest(RequestInterface $request); public function getStatusCode(); public function setStatusCode($statusCode); public function getReasonPhrase(); public function setReasonPhrase($reasonPhrase); }
34. January 28th, 2014 PSR-7 HTTP Message - DRAFT Michael Dowling
35. August 29th, 2014 PSR-7 HTTP Message - Retracted Michael Dowling
36. Matthew Weier O'Phinney
37. phly/http http://github.com/phly/http (similar to node's http.Server)
38. phly/conduit http://github.com/phly/conduit (a port of Sencha Connect)
39. September 26th, 2014 PSR-7 HTTP Message Interfaces Matthew Weier O'Phinney
40. In 3 Days PSR-7 will be accepted
41. Concepts & Interfaces
43. Immutability Messages and URIs are modeled as value objects
44. class Request implements RequestInterface { public function withMethod($method) { $new = clone $this; $new->method = $method; return $new; } }
45. use Phly\Http\Request; use Phly\Http\Uri; $request = (new Request()) ->withUri(new Uri('http://example.com')) ->withMethod('GET');
46. use Phly\Http\Request; use Phly\Http\Uri; $request = (new Request()) ->withUri(new Uri('http://example.com')) ->withMethod('GET'); // this does nothing to $request. $request->withAddedHeader( 'Content-Type', 'application/json' );
47. use Phly\Http\Request; use Phly\Http\Uri; $request = (new Request()) ->withUri(new Uri('http://example.com')) ->withMethod('GET'); // this is probably what you want. $request = $request->withAddedHeader( 'Content-Type', 'application/json' );
48. Messages
49. <message line> Header: value Another-Header: value Message body
50. Headers
51. // Returns an empty array if not found: $header = $message->getHeader('Accept'); // Returns an empty string if not found: $header = $message->getHeaderLine('Accept'); // Test for a header: if (! $message->hasHeader('Accept')) { } // If the header has multiple values, fetch them // as an array: $values = $message->getHeader('X-Foo'); // Or as a comma-separated string: $values = $message->getHeaderLine('X-Foo');
52. $message = $message ->withHeader('foo', 'bar') ->withAddedHeader('foo', 'baz'); // 'bar, baz' $header = $message->getHeaderLine('foo'); // ['bar', 'baz'] $header = $message->getHeader('foo'); // [ 'foo' => ['bar', 'baz'] ] foreach ($message->getHeaders() as $header => $values) { }
53. Host header Set from URI if not specified otherwise
54. Host header Calling withUri updates Host header by default
55. Host header You can pass true to $preserveHost
56. Streams Message Bodies
57. Allows implementations to work with large message bodies
58. Strings? php://memory or php://temp
59. $message = $message->withBody(new Stream('php://temp')); $message->getBody()->write('This is my content!');
60. Immutability cannot be enforced!
61. Use read-only streams for server-side requests and client-side responses
62. Requests
63. URI
64. // https://api.example.com $uri = $uri->withScheme('https')->withHost('api.example.com'); $usersUri = $uri->withPath('/v2/users'); $booksUri = $uri->withPath('/v2/books'); // https://api.example.com/v2/users?limit=10 $getUsersRequest = (new Request()) ->withMethod('GET') ->withUri($usersUri->withQuery('?limit=10')); // https://api.example.com/v2/users $postUsersRequest = (new Request()) ->withMethod('POST') ->withUri($usersUri); // https://api.example.com/v2/books $getBooksRequest = (new Request()) ->withMethod('GET') ->withUri($booksUri);
65. Server Requests
66. CGI + SAPI $_COOKIE • $_GET • $_POST • $_FILES • $_SERVER
67. Attributes
68. $country = $this->resolveCountryForRequest($request); if ($country) { $request = $request->withAttribute( 'geocode.country', $country ); } // ... $country = $request->getAttribute('geocode.country'); if ($country) { // }
69. Uploaded Files
70. Given file input names files[0] and files[1] What you might expect: [ 'files' => [ 0 => [ 'name' => 'file0.txt', 'type' => 'text/plain', /* etc. */ ], 1 => [ 'name' => 'file1.html', 'type' => 'text/html', /* etc. */ ], ], ];
71. Given file input names files[0] and files[1] What you actually get: [ 'files' => [ 'name' => [ 0 => 'file0.txt', 1 => 'file1.html', ], 'type' => [ 0 => 'text/plain', 1 => 'text/html', ], /* etc. */ ], ]
72. PSR-7 enforces a normalized $_FILES
73. $file0 = $request->getUploadedFiles()['files'][0]; $file1 = $request->getUploadedFiles()['files'][1]; printf( "Received the files %s and %s", $file0->getClientFilename(), $file1->getClientFilename() ); // "Received the files file0.txt and file1.html"
74. Underlying "filename" is protected // Move a file to an upload directory $filename = sprintf( '%s.%s', create_uuid(), pathinfo($file0->getClientFilename(), PATHINFO_EXTENSION) ); $file0->moveTo(DATA_DIR . '/' . $filename); // Stream a file to Amazon S3. // Assume $s3wrapper is a PHP stream that will write to S3, and that // Psr7StreamWrapper is a class that will decorate a StreamInterface as a PHP // StreamWrapper. $stream = new Psr7StreamWrapper($file1->getStream()); stream_copy_to_stream($stream, $s3wrapper);
75. Parsed Body
76. application/x-www-form-urlencoded multipart/form-data $_POST
77. function ($request, $response, $next) { $contentType = $request->getHeaderLine('Content-Type'); if ('application/json' === $contentType) { $json = json_decode($request->getBody(), true); $request = $request->withParsedBody($json); } return $next( $request, $response ); }
78. Middleware
79. function ($request, $response, $next) { return $next( $request, $response ); }
80. function ($request, $response, $next) { $response = $next( $request, $response ); return $response->withAddedHeader( 'X-Clacks-Overhead', 'GNU Terry Pratchett' ); }
81. namespace Acme; class ClacksOverhead { public function __invoke($request, $response, $next) { $response = $next( $request, $response ); return $response->withAddedHeader( 'X-Clacks-Overhead', 'GNU Terry Pratchett' ); } }
82. Laravel: on root request // app/Http/Kernel.php class Kernel { protected $routeMiddleware = [ 'clacks' => 'Acme\ClacksOverhead', ]; } // routes.php Route::get('/',['middleware'=>'clacks', function() { return view('home'); }]);
83. Laravel: on every request // app/Http/Kernel.php class Kernel { protected $middleware = [ 'Acme\ClacksOverhead', ]; }
84. Conduit: on every request $app->pipe(new \Acme\ClacksOverhead());
85. What do we want? Re-use at the web layer! — http://stackphp.com
86. Implementations phly/http, Conduit, Slim, Guzzle, Aura.Router, AWS SDK
87. Questions? @beausimensen • @thatpodcast https://beau.io/talks