The document discusses building applications without frameworks by using Symfony components independently. It describes how to handle HTTP requests and responses with the HttpFoundation component, map URLs to routes with the Routing component, manage service dependencies with DependencyInjection, and build an application kernel and controllers to tie it all together without relying on an existing framework.

1. symfony
without the framework
Tomasz Kowalczyk @tmmx

4. introduction

5. framework

6. Hollywood principle
"don't call us, we'll call you"

7. spaghetti
monolith
components

8. no framework
own framework
framework everywhere
no framework

9. framework agnostic

11. components

12. HttpFoundation

13. HTTP request → Request
Response → HTTP response

14. $request = Request::createFromGlobals();
$request = Request::create('/path' /* data */);
$request = new Request(/* data */);
$get = $request->query->all();
$post = $request->request->all();
$files = $request->files->all();
$attributes = $request->attributes->all();
$cookies = $request->cookies->all();
$server = $request->server->all();
$headers = $request->headers->all();

15. $response = new Response('content', Response::HTTP_OK);
$response = new JsonResponse(['key' => 'val']);
$response = new BinaryFileResponse();
$response = new StreamedResponse();
$response = new RedirectResponse();
$content = $response->getContent();
$code = $response->getStatusCode();
$success = $response->isSuccessful();
$is404 = $response->isNotFound();
$response->send();

16. class Response
{
const HTTP_CONTINUE = 100;
const HTTP_SWITCHING_PROTOCOLS = 101;
const HTTP_PROCESSING = 102; // RFC2518
const HTTP_OK = 200;
const HTTP_CREATED = 201;
const HTTP_ACCEPTED = 202;
const HTTP_NON_AUTHORITATIVE_INFORMATION = 203;
const HTTP_NO_CONTENT = 204;
const HTTP_RESET_CONTENT = 205;
const HTTP_PARTIAL_CONTENT = 206;
const HTTP_MULTI_STATUS = 207; // RFC4918
const HTTP_ALREADY_REPORTED = 208; // RFC5842
const HTTP_IM_USED = 226; // RFC3229
const HTTP_MULTIPLE_CHOICES = 300;
const HTTP_MOVED_PERMANENTLY = 301;
const HTTP_FOUND = 302;
const HTTP_SEE_OTHER = 303;
const HTTP_NOT_MODIFIED = 304;
const HTTP_USE_PROXY = 305;
const HTTP_RESERVED = 306;
const HTTP_TEMPORARY_REDIRECT = 307;
const HTTP_PERMANENTLY_REDIRECT = 308; // RFC7238
const HTTP_BAD_REQUEST = 400;
const HTTP_UNAUTHORIZED = 401;
const HTTP_PAYMENT_REQUIRED = 402;
const HTTP_FORBIDDEN = 403;
const HTTP_NOT_FOUND = 404;
const HTTP_METHOD_NOT_ALLOWED = 405;
const HTTP_NOT_ACCEPTABLE = 406;
const HTTP_PROXY_AUTHENTICATION_REQUIRED = 407;
const HTTP_REQUEST_TIMEOUT = 408;
}
class Response
{
const HTTP_CONFLICT = 409;
const HTTP_GONE = 410;
const HTTP_LENGTH_REQUIRED = 411;
const HTTP_PRECONDITION_FAILED = 412;
const HTTP_REQUEST_ENTITY_TOO_LARGE = 413;
const HTTP_REQUEST_URI_TOO_LONG = 414;
const HTTP_UNSUPPORTED_MEDIA_TYPE = 415;
const HTTP_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
const HTTP_EXPECTATION_FAILED = 417;
const HTTP_I_AM_A_TEAPOT = 418; // RFC2324
const HTTP_MISDIRECTED_REQUEST = 421; // RFC7540
const HTTP_UNPROCESSABLE_ENTITY = 422; // RFC4918
const HTTP_LOCKED = 423; // RFC4918
const HTTP_FAILED_DEPENDENCY = 424; // RFC4918
const HTTP_DIDNT_FIT_INTO_MY_SLIDE_EASTER_EGG = 425; // RFC2817
const HTTP_UPGRADE_REQUIRED = 426; // RFC2817
const HTTP_PRECONDITION_REQUIRED = 428; // RFC6585
const HTTP_TOO_MANY_REQUESTS = 429; // RFC6585
const HTTP_REQUEST_HEADER_FIELDS_TOO_LARGE = 431; // RFC6585
const HTTP_UNAVAILABLE_FOR_LEGAL_REASONS = 451;
const HTTP_INTERNAL_SERVER_ERROR = 500;
const HTTP_NOT_IMPLEMENTED = 501;
const HTTP_BAD_GATEWAY = 502;
const HTTP_SERVICE_UNAVAILABLE = 503;
const HTTP_GATEWAY_TIMEOUT = 504;
const HTTP_VERSION_NOT_SUPPORTED = 505;
const HTTP_VARIANT_ALSO_NEGOTIATES_EXPERIMENTAL = 506; // RFC2295
const HTTP_INSUFFICIENT_STORAGE = 507; // RFC4918
const HTTP_LOOP_DETECTED = 508; // RFC5842
const HTTP_NOT_EXTENDED = 510; // RFC2774
const HTTP_NETWORK_AUTHENTICATION_REQUIRED = 511; // RFC6585
}

17. HttpKernel

18. Request → Response

19. interface HttpKernelInterface
{
public function handle(
Request $request,
$type = self::MASTER_REQUEST,
$catch = true
);
}

20. final class AppKernel implements HttpKernelInterface
{
public function handle(
Request $request,
$type = self::MASTER_REQUEST,
$catch = true
): Response {
return new Response('Success!');
}
}

21. Routing

22. url → route
request → route
route → url

23. class Router {
public function __construct(
LoaderInterface $loader,
$resource,
array $options = array(),
RequestContext $context = null,
LoggerInterface $logger = null
) {
// ...
}
}

24. $path = __DIR__.'/../etc';
$loader = new YamlFileLoader(new FileLocator($path));
$router = new Router($loader, 'routing.yaml');

25. user.create:
path: /users
methods: [POST]
defaults:
_controller: user.controller:create
user.view:
path: /users/{id}
methods: [GET]
defaults:
_controller: user.controller:view

26. $request = Request::createFromGlobals();
$context = new RequestContext();
$context->fromRequest($request);
$router->setContext($context);
$route = $router->match('/users');
$route = $router->matchRequest($request);
$request->attributes->replace($route);
$url = $router->generate('user.view', [
'id' => '6f8f2d43-a907-4671-a96c-895e1354984f',
]);

27. DependencyInjection

28. id → service
name → parameter

29. $builder = new ContainerBuilder();
$builder->set('service.id', $instance);
$builder->setParameter('parameter.name', 'value');
$builder->setDefinition('svc', new Definition(Service::class, [
new Reference('service.id'),
new Parameter('parameter.name'),
]));
$svc = $builder->get('svc');

30. $builder = new ContainerBuilder();
$loader = new YamlFileLoader($builder, new FileLocator('etc'));
$loader->load('services.yaml');
$builder->compile();
$dumper = new PhpDumper($builder);
$code = $dumper->dump(['class' => 'AppContainer']);
file_put_contents(__DIR__.'/container.php', $code);

31. services:
routing:
class: SymfonyComponentRoutingRouter
arguments: ['@routing.loader', 'routing.yaml']
routing.loader:
class: SymfonyComponentRoutingLoaderYamlFileLoader
arguments: ['@routing.locator']
routing.locator:
class: SymfonyComponentConfigFileLocator
arguments: ['../etc']

32. class AppContainer extends Container
{
protected function getRoutingService()
{
return $this->services['routing'] =
new SymfonyComponentRoutingRouter(
new SymfonyComponentRoutingLoaderYamlFileLoader(
new SymfonyComponentConfigFileLocator('../etc')
),
'routing.yaml'
);
}
}

33. Console
EventDispatcher
Form
Twig
Validator
Yaml

34. Asset
BrowserKit
Config
Debug
ExpressionLanguage
Filesystem
Finder
Process
PropertyAccess
PropertyInfo
Security
Serializer
Translation
Workflow

35. application

36. entry point

37. require __DIR__.'/../../../vendor/autoload.php';
require __DIR__.'/../var/cache/AppContainer.php';
$request = Request::createFromGlobals();
$kernel = new AppKernel(new AppContainer());
$response = $kernel->handle($request);
$response->send();

38. kernel

39. final class AppKernel implements HttpKernelInterface
{
private $container;
public function __construct(AppContainer $container)
{
$this->container = $container;
}
public function handle(Request $request, $type, $catch)
{
// to be continued...
}
}

40. $routing = $this->container->get('routing');
$context = new RequestContext();
$context->fromRequest($request);
$routing->setContext($context);
$route = $routing->matchRequest($request);
$request->attributes->replace($route);
[$ctrl, $action] = explode(':', $route['_controller'], 2);
return $container->get($ctrl)->{$action.'Action'}($request);

41. $builder = new ContainerBuilder();
$loader = new YamlFileLoader($builder, new FileLocator('etc'));
$loader->load('services.yaml');
$builder->compile();
$dumper = new PhpDumper($builder);
file_put_contents('AppContainer.php', $dumper->dump([
'class' => 'AppContainer',
]));

42. $loader = new YamlFileLoader(new FileLocator(['etc']));
$routing = new Router($loader, 'routing.yaml', [
'cache_dir' => $target,
]);
$routing->match('/');

43. controller

44. final class UserController
{
private $users;
public function __construct(UserRepositoryInterface $users)
{
$this->users = $users;
}
public function viewAction(Request $request)
{
// to be continued...
}
}

45. $id = $request->attributes->get('id');
try {
$user = $this->users->findById(new UserId($id));
} catch(UserNotFoundException $e) {
return new JsonResponse(null, Response::HTTP_NOT_FOUND);
}
return new JsonResponse($user->toArray(), Response::HTTP_OK);

46. services:
user.controller:
class: ApplicationWebControllerUserController
arguments: ['@user.repository']
user.repository:
alias: user.repository.doctrine
user.repository.doctrine:
class: ApplicationWebRepositoryDoctrineUserRepository
arguments: ['@doctrine.em']
user.repository.memory:
class: ApplicationWebRepositoryMemoryUserRepository

47. repository

48. final class MemoryUserRepository implements UserRepositoryInterface
{
private $users = [];
public function findById(UserId $id): ?User
{
return $this->users[$id->toString()] ?? null;
}
public function add(User $user)
{
$this->users[$user->getId()->toString()] = $user;
}
}

49. final class DoctrineUserRepository implements UserRepositoryInterface
{
private $em;
public function __construct(EntityManagerInterface $em)
{
$this->em = $em;
}
public function findByUuid(UuidInterface $uuid)
{
return $this->em->find(User::class, $uuid->toString());
}
public function add(User $user)
{
$this->em->persist($user);
}
}

50. directory structure

51. Application
﹂src
﹂Domain
﹂User.php
﹂UserId.php
﹂UserRepositoryInterface.php
﹂Infrastructure
﹂Persistence
﹂User
﹂MemoryUserRepository.php
﹂DoctrineOrmUserRepository.php
﹂tests
﹂Domain
﹂UserTest.php

52. Application
﹂apps
﹂api
﹂etc
﹂routing.yaml
﹂services.yaml
﹂src
﹂Controller
﹂UserController.php
﹂Service
﹂TokenService.php
﹂AppKernel.php
﹂web
﹂app.php

53. Application
﹂apps
﹂api
﹂var
﹂cache
﹂router.php
﹂container.php
﹂logs
﹂error.log
﹂features
﹂user-auth.feature
﹂tests
﹂UserTest.php

54. library

55. directory structure

56. Library
﹂src
﹂Provider
﹂ProviderInterface.php
﹂AgnosticProvider.php
﹂Agnostic.php
﹂tests
﹂AgnosticTest.php

57. bundle

58. Library
﹂bundle
﹂etc
﹂services.yaml
﹂src
﹂DependencyInjection
﹂Configuration.php
﹂AgnosticExtension.php
﹂AgnosticBundle.php
﹂tests
﹂AgnosticBundleTest.php

59. {
// ...
"autoload": {
"psr-4": {
"ThunderAgnostic": "src",
"ThunderAgnosticTests": "tests",
"ThunderAgnosticBundle": "bundle/src"
}
}
// ...
}

60. essence

61. freedom

62. maintainability

63. testability

64. bundles

65. legacy

66. summary

67. workshop

68. questions?
GitHub /thunderer
Twitter @tmmx

69. Resources
https://symfony.com/components
http://wiki.c2.com/?HollywoodPrinciple
https://github.com/mattia-battiston/clean-architecture-example
http://fabien.potencier.org/create-your-own-framework-on-top-of-the-symfony2-components-part-1.html
http://symfony.com/doc/current/create_framework/index.html
https://matthiasnoback.nl/2014/06/how-to-create-framework-independent-controllers/
Images
https://www.flickr.com/photos/rob-sinclair/3476258575 (CC-BY-SA, parts)

70. thanks!
GitHub /thunderer
Twitter @tmmx