Slides from a talk I gave at CakeFest 2016, about the upcoming changes to CakePHP to support PSR7

1. The Future of HTTP
In CakePHP

2. First, the Present

3. Request & Response
Added in 2.0.0

4. Symfony HttpKernel
& StackPHP

5. Symfony all
the Things

6. PSR-7
HTTP message interfaces

7. What’s the Problem?

8. HTTP in PHP is :(

9. $_POST
Only works for POST methods and url-encoded
data.

10. $_SERVER
No-consistency, or normalization

11. Request URI
Hard to find.

12. File Uploads
A pretty big mess.

13. Frameworks to
the Rescue!

14. Not Invented Here
Every framework has their own HTTP stack

15. No Shared Solutions
Sharing is caring

16. What do other
languages do?

17. Python
Web Server Gateway Interface

18. Ruby
Rack

19. Go-Lang
http module in stdlib

20. Common Traits
All these platforms have a single implementation.

21. PSR-7

22. Requests &
Responses

23. Requests

24. Immutable
All PSR7 objects are immutable*

25. // Read a header as text
$value = $request->getHeaderLine(‘Content-Type’);
// Read header as an array
$value = $request->getHeader(‘Content-Type’);
// Read all the headers
$headers = $request->getHeaders();
Reading Headers

26. // Get an array of cookie values.
$cookies = $request->getCookieParams();
// Get a list of UploadedFile objects
$files = $request->getUploadedFiles();
// Read the file data.
$files[0]->getStream();
$files[0]->getSize();
$files[0]->getClientFileName();
// Move the file.
$files[0]->moveTo($targetPath);
Cookies & Files

27. // Get the URI
$uri = $request->getUri();
// Read data out of the URI.
$path = $uri->getPath();
$query = $uri->getQuery();
$host = $uri->getHost();
URL data

28. // Get the application base dir
$base = $request->getAttribute(‘base’);
// Get the application webroot
$webroot = $request->getAttribute(‘webroot’);
// Get the routing parameters
$params = $request->getAttribute(‘params’);
Request Attributes

29. Responses

30. Also Immutable

31. // Bodies are also Streams.
$body = new Stream(‘php://memory');
$body->write(‘{“ok”:true}’);
// Build up a response.
$res->withHeader(‘Content-Type’, ‘application/json’)
->withStatus(204)
->withBody($body);
Building Responses

32. Middleware

33. CORS
Exceptions
Assets
Routes
App

34. CORS
Exceptions
Assets
Routes
App
Request
Response

35. CORS
Exceptions
Assets
Routes
App
Request
Response

36. 1. Must accept a Request, Response and ‘next’
2. Must return a Response, or call ‘next’
3. No more Rules.
Middleware Rules

37. Middleware
Examples

38. $middleware = new CakeHttpMiddlewareStack();
// Catch any exceptions in the lower layers.
$middleware->push(new ErrorHandlerMiddleware());
// Handle plugin/theme assets
$middleware->push(new AssetMiddleware());
// Apply routing
$middleware->push(new RoutingMiddleware());
// Apply CORS at the first middleware
$middleware->prepend(new CorsMiddleware());
Setup Middleware

39. // Using closures
$wow = function ($req, $res, $next) {
$res = $res->withHeader(‘X-Wow’, ‘Wow’);
return $next($req, $res);
};
// Add to a middleware stack
$middleware->push($wow);
Middleware

40. class WowMiddleware
{
public function __invoke($res, $req, $next)
{
$res = $res->withHeader(‘X-Wow’, ‘Wow’);
return $next($req, $res);
}
}
// Add to a middleware stack
$middleware->push(new WowMiddleware());
Middleware

41. HttpClient

42. $client = new CakeHttpClient();
$res = $client->get(‘http://cakephp.org');
// Use PSR7 methods.
$status = $res->getStatusCode();
$contentType = $res->getHeaderLine(‘Content-Type’);
$body = $res->getBody()->getContents();
Client Example

43. Fully backwards
compatible
Client Responses still support the current
interface.

45. Sounds Nice, but
is upgrading going to suck?

46. Nope
It should be painless really.

47. Timeline
Now
3.3 - Fall 2016
3.4 - Early 2017
4.0 - ?

48. PSR-7 in 3.3.0
Opt-in stack that replaces DispatcherFilters

49. require dirname(__DIR__) . '/vendor/autoload.php';
use CakeHttpServer;
use AppApplication;
// Bind your application to the server.
$app = new Application(dirname(__DIR__) . ‘/config');
$server = new Server($app);
// Run the request/response and emit the response
$server->emit($server->run());
index.php of the future

50. class Application extends BaseApplication
{
public function middleware($middleware)
{
// Catch any exceptions in the lower layers.
$middleware->push(new ErrorHandlerMiddleware());
// Handle plugin/theme assets
$middleware->push(new AssetMiddleware());
// Apply routing
$middleware->push(new RoutingMiddleware());
return $middleware;
}
}
Application Class

51. 3.4.0
NetworkRequest will implement PSR7

52. Future 3.x.0
Runtime errors on deprecated methods.

53. 4.0.0
Clean up. Remove deprecations.

54. In Review
1. PSR7 middleware is coming as an opt-in feature for 3.3.0
2. New applications will default to the new HTTP stack in 3.3.0
3. Controllers will have access to PSR7 methods in 3.4.0
4. Runtime deprecations will be introduced in a future 3.x
5. The code you write today will continue to work until 4.0.0.

55. Thank You
Github - markstory
Twitter - mark_story
https://joind.in/talk/3b577