Building RESTful APIs with Symfony Components

Built around the HTTP specification, Symfony components provide a rock solid foundation for building RESTful APIs, whether we are using the full framework or not. In this session we will see how to successfully deal with problems such as how to adapt our models to the desired representations back and forth, authentication strategies, some tips and tricks to test effectively our APIs and also how to apply these concepts to migrate effectively a legacy application, based upon real use cases.

Transcript

1. Building RESTful APIs
   with Symfony Components
   Victoria Quirante 16-17th Feb. 2017
   

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2. I work at Limenius
   We build tailor-made projects with
   Symfony and React
   Most projects require the
   implementation of an API
   Symfony Components provide a
   rock-solid foundation for building APIs
   Victoria Quirante
   @vicqr
   victoria@limenius.com
   

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3. I. INTRODUCTION
   

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4. Why would I want my API
   to be RESTful?
   

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5. Possible reasons AGAINST
   Perhaps I can think of a better way to structure an API
   

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6. Possible reasons AGAINST
   Perhaps I can think of a better way to structure an API
   REST seems very controversial and confusing in some points
   

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7. Main reasons to go for REST
   REST makes the most of HTTP
   

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8. Main reasons to go for REST
   REST makes the most of HTTP
   It means to have a common language
   

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9. Main reasons to go for REST
   REST makes the most of HTTP
   It means to have a common language
   These are very powerful reasons
   

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10. What you already know about REST
    

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11. Sane way to approach REST
    

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12. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    

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13. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    Use nouns for
    the resources!
    

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14. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    Use nouns for
    the resources!
    Use HTTP verbs!
    

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15. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    Use HTTP verbs!
    Use nouns for
    the resources!
    Return meaningful
    status codes!
    

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16. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    2. Be aware of the grey areas / controversial points
    

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17. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    2. Be aware of the grey areas / controversial points
    Do I have to return the
    created/updated resource?
    

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18. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    2. Be aware of the grey areas / controversial points
    Do I have to return the
    created/updated resource?
    Can I have /recipes.json and
    /recipes.html?
    

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19. Sane way to approach REST
    “Remember the "RE" in REST stands for "REpresentational" which means we are talking about representation of state.
    Therefore a single URI should be used by resource as the unique identifier. Instead to get different representations we
    should use media types.”
    Lukas K. Smith (FOSRestBundle author)
    http://pooteeweet.org/blog/2248
    Can I have /recipes.json and
    /recipes.html?
    

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20. Sane way to approach REST
    “Remember the "RE" in REST stands for "REpresentational" which means we are talking about representation of state.
    Therefore a single URI should be used by resource as the unique identifier. Instead to get different representations we
    should use media types.”
    Lukas K. Smith (FOSRestBundle author)
    http://pooteeweet.org/blog/2248
    “Section 6.2.1 does not say that content negotiation should be used all the time.”
    Roy T. Fielding (author of REST thesis and REST concept itself)
    https://groups.yahoo.com/neo/groups/rest-discuss/conversations/messages/5857
    Can I have /recipes.json and
    /recipes.html?
    

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21. Sane way to approach REST
    “Remember the "RE" in REST stands for "REpresentational" which means we are talking about representation of state.
    Therefore a single URI should be used by resource as the unique identifier. Instead to get different representations we
    should use media types.”
    Lukas K. Smith (FOSRestBundle author)
    http://pooteeweet.org/blog/2248
    “Section 6.2.1 does not say that content negotiation should be used all the time.”
    Roy T. Fielding (author of REST thesis and REST concept itself)
    https://groups.yahoo.com/neo/groups/rest-discuss/conversations/messages/5857
    Can I have /recipes.json and
    /recipes.html?
    

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22. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    2. Be aware of the grey areas / controversial points
    3. Choose a side in those…
    

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23. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    2. Be aware of the grey areas / controversial points
    3. Choose a side in those… … and stick to it
    

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24. Sane way to approach REST
    1. Learn the stuff that is commonly accepted
    2. Be aware of the grey areas / controversial points
    3. Choose a side in those… … and stick to it
    Be civilized and consistent
    

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27. Why Symfony & REST?
    

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28. Why Symfony & REST?
    REST is several things:
    - A very strict definition -that not many people fully understand
    - A battlefield
    - A way to make the most of HTTP
    

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29. Why Symfony & REST?
    REST is several things:
    - A very strict definition -that not many people fully understand
    - A battlefield
    - A way to make the most of HTTP
    “I don't like MVC because that's not how the web works. Symfony2 is an HTTP framework; it is
    a Request/Response framework. That's the big deal. The fundamental principles of Symfony2
    are centered around the HTTP specification.”
    Fabien Potencier
    

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30. Why Symfony & REST?
    REST ♥ HTTP
    Symfony ♥ HTTP
    

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31. Why Symfony
    Components?
    

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32. Symfony is two things
    1. A full stack framework
    

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33. Symfony is two things
    1. A full stack framework
    2. A set of independent
    components
    

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34. What are Symfony Components
    Set of decoupled and reusable PHP libraries
    You can use any in your own applications independently from the
    Symfony Framework
    Many popular PHP projects do so
    

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35. Components used in popular projects
    http://symfony.com/projects
    

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36. Doctrine
    http://symfony.com/projects
    

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37. Propel
    http://symfony.com/projects
    

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38. Silex
    http://symfony.com/projects
    

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39. Drupal
    http://symfony.com/projects
    

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40. Laravel
    http://symfony.com/projects
    

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41. Components that we are going to see in detail
    HttpFoundation
    Serializer
    Validator
    Form
    Guard
    

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42. Where/when can you apply this knowledge
    - Working with the full Symfony framework
    

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43. Where/when can you apply this knowledge
    - Working with the full Symfony framework
    - Using some of these components in some other framework
    

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44. Where/when can you apply this knowledge
    - Working with the full Symfony framework
    - Using some of these components in some other framework
    - Writing your own framework
    

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45. Where/when can you apply this knowledge
    - Working with the full Symfony framework
    - Using some of these components in some other framework
    - Writing your own framework
    https://symfony.com/doc/current/create_framework/index.html
    

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46. See repository
    https://github.com/VictoriaQ/rest-symfony-components
    

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47. II. SYMFONY COMPONENTS
    

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48. HttpFoundation
    Moving to an Object-Oriented
    approach
    HttpFoundation
    Serializer
    Validator
    Form
    Guard
    

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49. HttpFoundation - The idea
    Defines an object-oriented layer for the HTTP specification
    

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50. HttpFoundation - The idea
    In PHP:
    - Request represented by global variables
    - Response generated by some functions
    Defines an object-oriented layer for the HTTP specification
    

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51. HttpFoundation - The idea
    In PHP:
    - Request represented by global variables
    - Response generated by some functions
    HttpFoundation replaces global variables and functions by an object-oriented layer:
    - $_GET, $_POST, $_FILES, $_COOKIE... ----> Request()
    - echo(), header(), setcookie()... ----> Response()
    Defines an object-oriented layer for the HTTP specification
    

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52. HttpFoundation - Request()
    Holds information about the client request
    use Symfony\Component\HttpFoundation\Request;
    $request = Request::createFromGlobals();
    

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53. HttpFoundation - Request()
    Creates Request object based on current PHP global variables
    use Symfony\Component\HttpFoundation\Request;
    $request = Request::createFromGlobals();
    

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54. HttpFoundation - Request()
    Creates Request object based on current PHP global variables
    use Symfony\Component\HttpFoundation\Request;
    $request = new Request(
    $_GET,
    $_POST,
    array(),
    $_COOKIE,
    $_FILES,
    $_SERVER
    );
    

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55. HttpFoundation - Response()
    Holds information of what needs to be sent back to the client
    use Symfony\Component\HttpFoundation\Response;
    $response = new Response(
    'Content',
    Response::HTTP_OK,
    array('content-type' => 'text/html')
    );
    

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56. Let’s create a POST endpoint
    When I request "POST /recipes"
    Then the response status code should be 201
    

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57. Let’s create a POST endpoint
    use Symfony\Component\HttpFoundation\Request;
    $request = Request::createFromGlobals();
    $content = json_decode($request->getContent(), true);
    

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58. Let’s create a POST endpoint
    use Symfony\Component\HttpFoundation\Request;
    use Symfony\Component\HttpFoundation\Response;
    $request = Request::createFromGlobals();
    $content = json_decode($request->getContent(), true);
    // Here we would persist the data
    $response = new Response(json_encode(array('data' => 'Hi!'), 201);
    $response->headers->set('Content-Type', 'application/json');
    $response->headers->set('Location', '/recipes/1');
    

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59. Shortcut: JsonResponse()
    use Symfony\Component\HttpFoundation\Request;
    use Symfony\Component\HttpFoundation\JsonResponse;
    $request = Request::createFromGlobals();
    $content = json_decode($request->getContent(), true);
    // Here we would persist the data
    $response = new JsonResponse(array('data' => 'Hi!'), 201);
    $response->headers->set('Location', '/recipes/1');
    Sets ContentType to application/json and encodes to JSON
    

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60. And what about PSR-7?
    

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61. Symfony PSR-7 Bridge
    HttpFoundation has helped with homogenization across frameworks
    The PSR-7 Standard has meant a step further towards standardization
    Symfony 4 will likely embrace the PSR-7 Standard
    

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62. Symfony PSR-7 Bridge
    HttpFoundation has helped with homogenization across frameworks
    The PSR-7 Standard has meant a step further towards standardization
    Symfony 4 will likely embrace the PSR-7 Standard
    Until then, the Symfony PSR-7 Bridge makes HttpFoundation
    objects compatible with PSR-7
    

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63. Symfony PSR-7 Bridge
    use Symfony\Bridge\PsrHttpMessage\Factory\DiactorosFactory;
    use Symfony\Component\HttpFoundation\Request;
    use Symfony\Component\HttpFoundation\Response;
    $psr7Factory = new DiactorosFactory();
    // convert a Request
    $symfonyRequest = Request::createFromGlobals();
    $psrRequest = $psr7Factory->createRequest($symfonyRequest);
    // convert a Response
    $symfonyResponse = new Response('Content');
    $psrResponse = $psr7Factory->createResponse($symfonyResponse);
    This is how we can convert
    HttpFoundation objects to objects
    implementing HTTP message
    interfaces defined by the PSR-7
    

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64. Symfony PSR-7 Bridge
    use Symfony\Bridge\PsrHttpMessage\Factory\DiactorosFactory;
    use Symfony\Component\HttpFoundation\Request;
    use Symfony\Component\HttpFoundation\Response;
    $psr7Factory = new DiactorosFactory();
    // convert a Request
    $symfonyRequest = Request::createFromGlobals();
    $psrRequest = $psr7Factory->createRequest($symfonyRequest);
    // convert a Response
    $symfonyResponse = new Response('Content');
    $psrResponse = $psr7Factory->createResponse($symfonyResponse);
    This is how we can convert
    HttpFoundation objects to objects
    implementing HTTP message
    interfaces defined by the PSR-7
    https://inviqa.com/blog/introduction-psr-7-symfony
    

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65. PSR-7 middlewares
    AccessLog
    AttributeMapper
    AuraRouter
    AuraSession
    BasePath
    BasicAuthentication
    BlockSpam
    Cache
    ClientIp
    Cors
    Csp
    Csrf
    https://github.com/oscarotero/psr7-middlewares
    DebugBar
    Delay
    DetectDevice
    DigestAuthentication
    EncodingNegotiator
    ErrorHandler
    Expires
    FastRoute
    FormTimestamp
    Firewall
    FormatNegotiator
    Geolocate
    GoogleAnalytics
    Honeypot
    Https
    ImageTransformer
    IncludeResponse
    JsonSchema
    LanguageNegotiation
    LeagueRoute
    MethodOverride
    Minify
    Payload
    PhpSession
    Piwik
    ReadResponse
    Recaptcha
    Rename
    ResponseTime
    Robots
    SaveResponse
    Shutdown
    TrailingSlash
    Uuid
    Whoops
    Www
    Following PSR-7
    Standard allows you to
    use middlewares
    

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66. Serializer
    Getting representations of our
    objects, back and forth
    Serializer
    HttpFoundation
    Validator
    Form
    Guard
    

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67. Serializer - The idea
    $recipe = new Recipe();
    $recipe->setName($content['name']);
    $recipe->setEnergy($content['energy']);
    $recipe->setServings($content['servings']);
    ...
    The request -> Our object
    (manual deserialization)
    

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68. Serializer - The idea
    $recipe = new Recipe();
    $recipe->setName($content['name']);
    $recipe->setEnergy($content['energy']);
    $recipe->setServings($content['servings']);
    ...
    ...
    $responseData = [
    'id' => $recipe->getId(),
    'name' => $recipe->getName(),
    'energy' => $recipe->getEnergy(),
    'servings' => $recipe->getServings(),
    ];
    $response = new JsonResponse($responseData, 201);
    The request -> Our object
    (manual deserialization)
    Our object -> The response
    (manual serialization)
    

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69. Serializer - The idea
    $recipe = new Recipe();
    $recipe->setName($content['name']);
    $recipe->setEnergy($content['energy']);
    $recipe->setServings($content['servings']);
    ...
    ...
    $responseData = [
    'id' => $recipe->getId(),
    'name' => $recipe->getName(),
    'energy' => $recipe->getEnergy(),
    'servings' => $recipe->getServings(),
    ];
    $response = new JsonResponse($responseData, 201);
    A lot of repetitive, boring work!
    The request -> Our object
    (manual deserialization)
    Our object -> The response
    (manual serialization)
    

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70. Serializing
    $responseData = [
    'id' => $recipe->getId(),
    'name' => $recipe->getName(),
    'energy' => $recipe->getEnergy(),
    'servings' => $recipe->getServings(),
    ];
    $response = new JsonResponse($responseData, 201);
    Converting our object into a JSON response
    

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71. Serializing
    $responseData = [
    'id' => $recipe->getId(),
    'name' => $recipe->getName(),
    'energy' => $recipe->getEnergy(),
    'servings' => $recipe->getServings(),
    ];
    $response = new JsonResponse($responseData, 201);
    --------------
    $response = new Response($serializer->serialize($recipe, 'json'), 201);
    Converting our object into a JSON response
    

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72. Deserializing
    $recipe = new Recipe();
    $recipe->setName($content['name']);
    $recipe->setEnergy($content['energy']);
    $recipe->setServings($content['servings']);
    Converting the JSON content request into an object
    

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73. Deserializing
    $recipe = new Recipe();
    $recipe->setName($content['name']);
    $recipe->setEnergy($content['energy']);
    $recipe->setServings($content['servings']);
    ------------------
    $recipe = $serializer->deserialize($content, Recipe::class, 'json');
    Converting the JSON content request into an object
    

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74. Serializer - The idea
    Turns objects into a specific format, and the other way around
    

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75. Setting up the Serializer
    use Symfony\Component\Serializer\Serializer;
    use Symfony\Component\Serializer\Encoder\XmlEncoder;
    use Symfony\Component\Serializer\Encoder\JsonEncoder;
    use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
    $encoders = array(new XmlEncoder(), new JsonEncoder());
    $normalizers = array(new ObjectNormalizer());
    serializer = new Serializer($normalizers, $encoders);
    

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76. Setting up the Serializer
    use Symfony\Component\Serializer\Serializer;
    use Symfony\Component\Serializer\Encoder\XmlEncoder;
    use Symfony\Component\Serializer\Encoder\JsonEncoder;
    use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
    $encoders = array(new XmlEncoder(), new JsonEncoder());
    $normalizers = array(new ObjectNormalizer());
    serializer = new Serializer($normalizers, $encoders);
    http://symfony.com/doc/current/components/serializer.html
    

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77. Representation in API
    !=
    what we have in DB
    

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78. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    

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79. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    I may want to name this “username”
    

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80. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    I may want to name this “username”
    Don’t what to expose it!
    

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81. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    I may want to name this “username”
    Don’t what to expose it!
    Only in the profile, not in the list
    

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82. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    I may want to name this “username”
    Don’t what to expose it!
    We want to add “thumb_”
    Only in the profile, not in the list
    

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83. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    I may want to name this “username”
    Don’t what to expose it!
    Only in the profile, not in the list
    We want to add “thumb_”
    Only in version 2 of the API
    

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84. Representation in API != what we have in DB
    {
    id: 9,
    name: "victoriaq",
    password: "encryptedPassword",
    email: "victoria@limenius.com",
    avatar: "avatar.jpg",
    twitter_handler: "vicqr",
    profile: {
    id: 19,
    bio: "My bio."
    }
    }
    I may want to name this “username”
    Don’t what to expose it!
    Only in the profile, not in the list
    We want to add “thumb_”
    Only in version 2 of the API
    I’d like to show it as any other field
    

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85. Annotations
    MaxDepth
    - Detect and limit the serialization depth
    - Especially useful when serializing large trees
    

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86. Annotations
    MaxDepth
    - Detect and limit the serialization depth
    - Especially useful when serializing large trees
    Groups
    - Sometimes, you want to serialize different sets of attributes from your entities
    - Groups are a handy way to achieve this need
    

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87. Let’s create a GET endpoint
    When I request "GET /recipes"
    Then the response status code should be 200
    And only the following properties should exist:
    “”
    name
    servings
    “”
    

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88. Let’s create a GET endpoint
    class Recipe
    {
    /**
    * @Groups({"detail", "overview"})
    */
    public $name;
    /**
    * @Groups({"detail"})
    */
    public $energy;
    /**
    * @Groups({"detail", "overview"})
    */
    public $servings;
    }
    

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89. Let’s create a GET endpoint
    class Recipe
    {
    /**
    * @Groups({"detail", "overview"})
    */
    public $name;
    /**
    * @Groups({"detail"})
    */
    public $energy;
    /**
    * @Groups({"detail", "overview"})
    */
    public $servings;
    }
    

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90. Let’s create a GET endpoint
    $groups = ['groups' => ['overview']];
    $response = new Response($serializer->serialize($recipes, 'json', $groups), 201);
    $response->headers->set('Content-Type', 'application/json');
    return $response;
    Now we can serialize only the group overview, if we want
    

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91. Creating your custom normalizers
    For example, to serialize attributes with a different name
    

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92. Creating your custom normalizers
    use Symfony\Component\Serializer\NameConverter\NameConverterInterface;
    class OrgPrefixNameConverter implements NameConverterInterface
    {
    public function normalize($propertyName)
    {
    return 'prefix_'.$propertyName;
    }
    public function denormalize($propertyName)
    {
    // remove prefix_ prefix
    return 'prefix_' === substr($propertyName, 0, 7) ? substr($propertyName, 7) : $propertyName;
    }
    }
    For example, to serialize attributes with a different name
    

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93. Validator
    Enforcing sanity
    Validator
    HttpFoundation
    Serializer
    Form
    Guard
    

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94. Validator - The idea
    The values sent to our DB must meet certain constraints
    We can’t leave that work to the DB itself
    We need a previous validation
    Provides tools to validate the incoming data
    

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95. Simplest example
    use Symfony\Component\Validator\Validation;
    use Symfony\Component\Validator\Constraints\Length;
    use Symfony\Component\Validator\Constraints\NotBlank;
    $validator = Validation::createValidator();
    $violations = $validator->validate('Spanish omelette', array(
    new Length(array('min' => 2))
    ));
    

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96. Simplest example
    use Symfony\Component\Validator\Validation;
    use Symfony\Component\Validator\Constraints\Length;
    use Symfony\Component\Validator\Constraints\NotBlank;
    $validator = Validation::createValidator();
    $violations = $validator->validate('Spanish omelette', array(
    new Length(array('min' => 2))
    ));
    Constraints...
    (rule formulation)
    

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97. Simplest example
    use Symfony\Component\Validator\Validation;
    use Symfony\Component\Validator\Constraints\Length;
    use Symfony\Component\Validator\Constraints\NotBlank;
    $validator = Validation::createValidator();
    $violations = $validator->validate('Spanish omelette', array(
    new Length(array('min' => 2))
    ));
    and validators
    (logic there)
    

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98. Simplest example
    use Symfony\Component\Validator\Validation;
    use Symfony\Component\Validator\Constraints\Length;
    use Symfony\Component\Validator\Constraints\NotBlank;
    $validator = Validation::createValidator();
    $violations = $validator->validate('Spanish omelette', array(
    new Length(array('min' => 2))
    ));
    What happens with more complex validations…
    such as validating an object?
    

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99. Validating objects
    /**
    * @ORM\Column(type="integer")
    * @Assert\NotBlank()
    * @Assert\GreaterThanOrEqual(
    * value=0,
    * message="This universe is not so lucky. This value must be at least zero"
    * )
    **/
    private $energy;
    /**
    * @ORM\Column(type="integer")
    * @Assert\NotBlank()
    **/
    private $servings;
    Validator needs to know
    which constraints apply to
    the object properties
    

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100. Validating objects
     /**
     * @ORM\Column(type="integer")
     * @Assert\NotBlank()
     * @Assert\GreaterThanOrEqual(
     * value=0,
     * message="This universe is not so lucky. This value must be at least zero"
     * )
     **/
     private $energy;
     /**
     * @ORM\Column(type="integer")
     * @Assert\NotBlank()
     **/
     private $servings;
     Annotations are handy, but it
     can be done with yml, xml,
     explicit PHP...
     

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101. Constraints
     https://symfony.com/doc/current/reference/constraints.html
     You have about 50 constraints defined in the Validator component
     (from NotNull to ISBN…)
     

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102. Constraints
     https://symfony.com/doc/current/reference/constraints.html
     You have about 50 constraints defined in the Validator component
     (from NotNull to ISBN…)
     And you can create your own
     

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103. Returning errors in our API
     if (0 !== count($violations)) {
     $errors = [];
     foreach ($violations as $violation) {
     $errors[$violation->getPropertyPath()] = $violation->getMessage();
     }
     $response = new JsonResponse($errors, 400);
     $response->send();
     return;
     }
     Good validation and error handling are key in an API
     

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104. Form
     Powering up validation and
     deserialization
     Form
     HttpFoundation
     Serializer
     Validator
     Guard
     

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105. Form - The idea
     Not much difference between handling an HTML form and API data
     Equivalent to deserializing + validating
     A powerful deserializer
     We can reuse work done in HTML forms
     Provides powerful validation plus serialization
     

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106. Form - The idea
     Not much difference between handling an HTML form and API data
     Equivalent to deserializing + validating
     A powerful deserializer
     We can reuse work done in HTML forms
     https://knpuniversity.com/screencast/symfony-rest/form-post
     

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107. Let’s create a PUT endpoint
     When I request "PUT /recipes/1"
     Then the response status code should be 200
     

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108. Let’s create a PUT endpoint
     $formFactory = Forms::createFormFactoryBuilder()
     ->addExtension(new ValidatorExtension($validator))
     ->getFormFactory();
     $data = json_decode($request->getContent(), true);
     $recipe = $this->getDoctrine()->getRepository('AppBundle:Recipe')->find($recipeId);
     $form = $formFactory->create(RecipeType::class, $recipe);
     $form->submit($data);
     if (!$form->isValid()) {
     $response = new Response($serializer->serialize($form, 'json'), 400);
     $response->headers->set('Content-Type', 'application/json');
     return $response;
     }
     

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109. Let’s create a PUT endpoint
     $formFactory = Forms::createFormFactoryBuilder()
     ->addExtension(new ValidatorExtension($validator))
     ->getFormFactory();
     $data = json_decode($request->getContent(), true);
     $recipe = $this->getDoctrine()->getRepository('AppBundle:Recipe')->find($recipeId);
     $form = $formFactory->create(RecipeType::class, $recipe);
     $form->submit($data);
     if (!$form->isValid()) {
     $response = new Response($serializer->serialize($form, 'json'), 400);
     $response->headers->set('Content-Type', 'application/json');
     return $response;
     }
     

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110. Let’s create a PUT endpoint
     $formFactory = Forms::createFormFactoryBuilder()
     ->addExtension(new ValidatorExtension($validator))
     ->getFormFactory();
     $data = json_decode($request->getContent(), true);
     $recipe = $this->getDoctrine()->getRepository('AppBundle:Recipe')->find($recipeId);
     $form = $formFactory->create(RecipeType::class, $recipe);
     $form->submit($data);
     if (!$form->isValid()) {
     $response = new Response($serializer->serialize($form, 'json'), 400);
     $response->headers->set('Content-Type', 'application/json');
     return $response;
     }
     

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111. Let’s create a PUT endpoint
     $formFactory = Forms::createFormFactoryBuilder()
     ->addExtension(new ValidatorExtension($validator))
     ->getFormFactory();
     $data = json_decode($request->getContent(), true);
     $recipe = $this->getDoctrine()->getRepository('AppBundle:Recipe')->find($recipeId);
     $form = $formFactory->create(RecipeType::class, $recipe);
     $form->submit($data);
     if (!$form->isValid()) {
     $response = new Response($serializer->serialize($form, 'json'), 400);
     $response->headers->set('Content-Type', 'application/json');
     return $response;
     }
     

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112. Let’s create a PUT endpoint
     $formFactory = Forms::createFormFactoryBuilder()
     ->addExtension(new ValidatorExtension($validator))
     ->getFormFactory();
     $data = json_decode($request->getContent(), true);
     $recipe = $this->getDoctrine()->getRepository('AppBundle:Recipe')->find($recipeId);
     $form = $formFactory->create(RecipeType::class, $recipe);
     $form->submit($data);
     if (!$form->isValid()) {
     $response = new Response($serializer->serialize($form, 'json'), 400);
     $response->headers->set('Content-Type', 'application/json');
     return $response;
     }
     

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113. Let’s create a PUT endpoint
     $formFactory = Forms::createFormFactoryBuilder()
     ->addExtension(new ValidatorExtension($validator))
     ->getFormFactory();
     $data = json_decode($request->getContent(), true);
     $recipe = $this->getDoctrine()->getRepository('AppBundle:Recipe')->find($recipeId);
     $form = $formFactory->create(RecipeType::class, $recipe);
     $form->submit($data);
     if (!$form->isValid()) {
     $response = new Response($serializer->serialize($form, 'json'), 400);
     $response->headers->set('Content-Type', 'application/json');
     return $response;
     }
     https://github.com/VictoriaQ/rest-symfony-components/commit/bd2e044d6a5269e4e415d8fadcf7710a9ede27de
     

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114. POST to create and PUT
     to update?
     

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115. On PUT and POST
     Common knowledge:
     - POST to create resources
     - PUT to update resources
     

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116. On PUT and POST
     Common knowledge:
     - POST to create resources
     - PUT to update resources
     Not true
     

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117. On PUT and POST
     Common knowledge:
     - POST to create resources
     - PUT to update resources
     Not true
     (but somehow true)
     

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118. On PUT and POST
     Common knowledge:
     - POST to create resources
     - PUT to update resources
     Not true
     (but somehow true)
     (some people get very angry with this)
     

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119. On PUT and POST
     PUT if:
     - The operation is idempotent
     - URI = address of the resource
     BOTH need to be true. Otherwise, POST.
     This is the whole truth
     

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120. And do I have to return
     the resource?
     

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121. Do I have to return the resource?
     Many say that we do not
     Some clients assume that we will
     

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122. Do I have to return the resource?
     Many say that we do not
     Some clients assume that we will
     As always, be consistent with your choices
     

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123. Guard
     Authenticating
     Guard
     HttpFoundation
     Serializer
     Validator
     Form
     

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124. Guard - The idea
     Security Component allows to implement authentication
     Very powerful and flexible… But complex too
     Simplifies the authentication provided by the Security Component
     

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125. Just about one class with seven methods
     We only need to implement GuardAuthenticationInterface
     

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126. Just about one class with seven methods
     We only need to implement GuardAuthenticationInterface
     With its seven methods:
     class TokenAuthenticator extends AbstractGuardAuthenticator implements Guard\GuardAuthenticatorInterface {
     public function getCredentials(Request $request)
     public function getUser($credentials, UserProviderInterface $userProvider)
     public function checkCredentials($credentials, UserInterface $user)
     public function onAuthenticationFailure(Request $request, AuthenticationException $exception)
     public function onAuthenticationSuccess(Request $request, TokenInterface $token, $providerKey)
     public function supportsRememberMe()
     public function start(Request $request, AuthenticationException $authException = null)
     }
     http://symfony.com/blog/new-in-symfony-2-8-guard-authentication-component
     

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127. Just about one class with seven methods
     We only need to implement GuardAuthenticationInterface
     With its seven methods:
     class TokenAuthenticator extends AbstractGuardAuthenticator implements Guard\GuardAuthenticatorInterface {
     public function getCredentials(Request $request)
     public function getUser($credentials, UserProviderInterface $userProvider)
     public function checkCredentials($credentials, UserInterface $user)
     public function onAuthenticationFailure(Request $request, AuthenticationException $exception)
     public function onAuthenticationSuccess(Request $request, TokenInterface $token, $providerKey)
     public function supportsRememberMe()
     public function start(Request $request, AuthenticationException $authException = null)
     }
     http://symfony.com/blog/new-in-symfony-2-8-guard-authentication-component
     

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128. But at this point
     You need EventDispatcher, HttpKernel, Routing...
     

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129. But at this point
     You need EventDispatcher, HttpKernel, Routing...
     Starts looking like a good idea to use a complete framework
     

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130. III. USING THE FULL FRAMEWORK
     

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131. Uses all these Components
     http://symfony.com/projects/symfonyfs (actually a few more)
     

     View Slide

132. Components and bundles
     - Component -> decoupled and reusable library
     - Bundle -> tied to the Symfony Framework
     

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133. Components and bundles
     - Component -> decoupled and reusable library
     - Bundle -> tied to the Symfony Framework
     Often you have:
     Functionality
     Library
     Integration with SF
     Configuration
     Dependency injection
     Bundle
     +
     

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134. Components and bundles
     - Component -> decoupled and reusable library
     - Bundle -> tied to the Symfony Framework
     Often you have:
     Functionality
     Library
     Integration with SF
     Configuration
     Dependency injection
     Bundle
     +
     Let’s see a few Bundles that can be useful for our API
     

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135. JMSSerializerBundle
     

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136. JMSSerializerBundle
     Another possibility for serialization / deserialization
     - JMSSerializer has lots of useful annotations
     - Perhaps easier to setup and start using than Sf Serializer
     - Sf Serializer is more about writing your own normalizers
     

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137. JMSSerializerBundle
     Some cool features:
     - Three exclusion strategies (Exclude, Groups, Versions)
     - Configurable properties (Virtual Props., Accessors)
     - Events provide extra flexibility
     - XML highly configurable
     Good alternative to Serializer, up to you
     

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138. FOSRestBundle
     

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139. FOSRestBundle
     Set of tools:
     - View layer that deals with the different representations
     - Body request decoder
     - Listener that performs content negotiation
     - Parameter validator and converter
     - ALLOW header manager
     - Exception decoder
     - Unified REST routing system
     

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140. FOSRestBundle
     Set of tools:
     - View layer that deals with the different representations
     - Body request decoder
     - Listener that performs content negotiation
     - Parameter validator and converter
     - ALLOW header manager
     - Exception decoder
     - Unified REST routing system
     You can live without it, but it is quite useful when you have it
     

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141. LexikJWTAuthenticationBundle
     

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142. LexikJWTAuthenticationBundle
     JSON Web Token (JWT) is a compact URL-safe means of
     representing claims to be transferred between two
     parties. The claims in a JWT are encoded as a JSON
     object that is digitally signed using JSON Web Signature
     (JWS).
     

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143. LexikJWTAuthenticationBundle
     JSON Web Token (JWT) is a compact URL-safe means of
     representing claims to be transferred between two
     parties. The claims in a JWT are encoded as a JSON
     object that is digitally signed using JSON Web Signature
     (JWS).
     Two built-in token encoders, based on:
     - namshi/jose
     - lcobucci/jwt
     

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144. LexikJWTAuthenticationBundle
     POST /login_check HTTP/1.1
     Host: localhost:8000
     Content-Type: application/json
     Accept: application/json
     Cache-Control: no-cache
     {"_username": "user",
     "_password": "userpass"}
     endpoint configured
     in security.yml
     credentials
     

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145. LexikJWTAuthenticationBundle
     {"token":"eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXUyJ9.eyJleHAiOjE0MzIzODc2ODcsInVzZXJuYW1l
     IjoidXNlciIsImlhdCI6IjE0MzIzMDEyODcifQ.QgtJ-C96gMDzl1syuRGdpIb02sGnC-oKyLFqiNMX9Lny
     hYV__R7itxLPEepOqzkhOiL-O7EdFEdqFjK9vRgk67MRgfKCh5Yuir9aUkVYeZXpyVOGUgPGDpHtFi74_G9
     EY4FGXzt7zhHoP_Y-6GwFSc_7HTeW7sm3ifGpYSlifyx3jmggkHoTc-1_kxXFdceoSCOoPf-uDaaQtLOwKF
     qUJCYaAcGXaS0FI_GDnIyX4bDCcPi3_6AvLLuSmfCaZqRofPvasANfhxRmE6iZ9wZ9dcKX1siPu7F_lFpJe
     3UgMy6hr3kDYPz5H4gOcu0A3JWV7lCIpThF8j-G1eN7PCIeLCQBpq08rkM9SrohWUiMcuqCQYjWIbB-jF0Z
     Uv762Cvv2Y-
     e9gqXsCYmg9NrLURLNJdce_Yl3QyWECYSKwaFkz8p8VTqrKtxrM0Gd-qNZ_uT4Hq8-BZ7ZDGCfQ0Dm4qC2P
     qXtPFfvmi_RQ9S2xmx93At0gBtLRrQPSqxv7ZfqtDjAKsCgOsMPU1yS-4h8s3Wxb4_flwvBZJbnHgkmFFR8
     -p_a8FwAHXoHXkPokTX-hZy-UjfV1x8N2F8u0_ndsHS0cZdFhX9grpBsRoR058YFTqFgAC-6s3d6AeAX7WX
     VIKu-
     x1qjcsrkNND2jxoEppZphT6ecC0JgT6ioGFuHYZWbA"}
     

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146. LexikJWTAuthenticationBundle
     GET /recipes/1 HTTP/1.1
     Host: localhost:8000
     Content-Type: application/json
     Accept: application/json
     Authorization: Bearer
     eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXUyJ9.eyJleHAiOjE0MzIzNzk0MjQsInVzZXJuYW1lIjoidXNlci
     IsImlhdCI6IjE0MzIyOTMwMjQifQ.Wb8NlbNNvCA5V7QxKoN_uYLmCRiqjt0ES5gIlvpyrBmVKMAXQ_cj6M
     NqbXcHp28NXNGJidcV2qJ1-8zWGkbHBDMZCAOp_JX74EXdeQYa0c2bV7HzKyUCEX8bOii25Jmt8YpWUa5og
     w58rWVhE-2CRn0fQS_gHn7d3Ke1w4NPjaLgnhSthZKfR2Ytd9U6A_3w6X2fS2R24DWWmb8KThMtSwXOtGVq
     EQVEnsro91RPHARg-na1ww_BnE-3Xas_427g84bsUHNIIlDs7BYAEF323h3AZrPB4Tx1tNabEWIsBJzEAKE
     LBDoCrqmspK0AFrGx-RIjiRMpMzDlTHMjt6hML7SO1y3AJbrD5AsxNLITtnaxfkFYl3n0XIH8Gd2ZRdFDsj
     XGPPZ6VLFHfUIe1BoPmLtFt5CK4PeDb-_BsbdA3tGEkVgfTrh9bSMY9mXZ-KCg8F8cbK5A-CqURqRFpTts1
     OBRUcOR1c6GtrPHpGsuoPGE90mTiOJPyajUK8lgdv1yBMt7WSEJNRXMLxetk57l53FLiLVObfV7D-LGC9R1
     8gIedzxmTXXxteV83izNuzQChAiRBU73W-5kjGkmpvr05Q_rd33dTn9wxEe0I0nnEK_MeSvqz2nH23xj7RU
     wGH
     qsrWlfVZZqZcVP59njex0LWWgb7PGKmJwL8ze2MrBft-U
     Provides a very simple way of authenticating
     

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147. BazingaHateoasBundle
     

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148. BazingaHateoasBundle
     Allows you to reach REST level 3
     Hypermedia As The Engine Of Application State
     

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149. BazingaHateoasBundle
     GET /recipes/1 HTTP/1.1
     Host: localhost:8000
     Content-Type: application/json
     Accept: application/json
     {
     "id":1,
     "name":"Spanish omelette",
     "energy":"500",
     "servings":4
     }
     

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150. BazingaHateoasBundle
     GET /recipes/1 HTTP/1.1
     Host: localhost:8000
     Content-Type: application/json
     Accept: application/json
     {
     "id":1,
     "name":"Spanish omelette",
     "energy":"500",
     "servings":4,
     "_links": {
     "self": {
     "href": "\/recipes\/1"
     }
     }
     }
     Level 3! :-)
     

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151. BazingaHateoasBundle
     use Doctrine\ORM\Mapping as ORM;
     use Hateoas\Configuration\Annotation as Hateoas;
     use JMS\Serializer\Annotation as Serializer;
     /**
     * Recipe
     *
     * @ORM\Table()
     * @ORM\Entity(repositoryClass="AppBundle\Entity\RecipeRepository")
     * @Hateoas\Relation("self",
     * href = @Hateoas\Route(
     * "fosrest_api_get_recipe",
     * parameters = { "id" = "expr(object.getId())" }))
     */
     class Recipe
     {
     …
     }
     

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152. BazingaHateoasBundle
     use Doctrine\ORM\Mapping as ORM;
     use Hateoas\Configuration\Annotation as Hateoas;
     use JMS\Serializer\Annotation as Serializer;
     /**
     * Recipe
     *
     * @ORM\Table()
     * @ORM\Entity(repositoryClass="AppBundle\Entity\RecipeRepository")
     * @Hateoas\Relation("self",
     * href = @Hateoas\Route(
     * "fosrest_api_get_recipe",
     * parameters = { "id" = "expr(object.getId())" }))
     */
     class Recipe
     {
     …
     }
     Potentially, allows you to reach level 3
     

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153. And do I actually HAVE
     TO reach level 3?
     

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154. Do I have to reach level 3 of REST?
     “If the engine of application state (and hence the
     API) is not being driven by hypertext, then it
     cannot be RESTful and cannot be a REST API.
     Period.”
     Roy T. Fielding (author of REST thesis and REST concept itself)
     http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
     Theoretically:
     

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155. Do I have to reach level 3 of REST?
     “If the engine of application state (and hence the
     API) is not being driven by hypertext, then it
     cannot be RESTful and cannot be a REST API.
     Period.”
     Theoretically: In the Real World:
     Roy T. Fielding (author of REST thesis and REST concept itself)
     http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
     

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156. Do I have to reach level 3 of REST?
     “If the engine of application state (and hence the
     API) is not being driven by hypertext, then it
     cannot be RESTful and cannot be a REST API.
     Period.”
     Theoretically: In the Real World:
     It is up to you, you have to evaluate
     Roy T. Fielding (author of REST thesis and REST concept itself)
     http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
     

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157. NelmioAPIDocBundle
     

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158. NelmioAPIDocBundle
     Documentation bundle
     You create documentation while coding
     Uses code introspection a lot
     

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159. NelmioAPIDocBundle
     Documentation bundle
     You create documentation while coding
     Uses code introspection a lot
     Easy to keep the documentation updated
     

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160. NelmioAPIDocBundle
     /**
     * Gets a Recipe
     * @ApiDoc(
     * resource=true,
     * section="recipe",
     * deprecated="true",
     * tags={"hi", "anothertag" = "#34a523"},
     * views = { "default", "v2" },
     * statusCodes = {
     * 200 = "Returned when successful",
     * 404 = "Returned when the recipe is not found"
     * })
     * @QueryParam(name="page", requirements="\d+", default="1", description="Page of the overview.")
     * @param ParamFetcher $paramFetcher
     * @return array
     */
     public function getPlatosAction(ParamFetcher $paramFetcher)
     {
     

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161. NelmioAPIDocBundle
     

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162. NelmioAPIDocBundle
     

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163. IV. TESTING
     

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164. Testing, some tips
     Invest some time in setting up a nice testing environment
     

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165. Testing, some tips
     Postman, easy to set-up
     Invest some time in setting up a nice testing environment
     

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166. Postman
     

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167. Testing, some tips
     Postman, easy to set-up
     Guzzle + PHPUnit, your bread and butter
     Invest some time in setting up a nice testing environment
     

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168. Guzzle
     $data = array(
     'name' => 'Spanish omelette',
     'energy' => 500,
     'servings' => 4
     );
     $request = $client->post('/recipes', null, json_encode($data));
     $response = $request->send();
     echo $response;
     

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169. Testing, some tips
     Postman, easy to set-up
     Guzzle + PHPUnit, your bread and butter
     Very important to handle errors properly
     Invest some time in setting up a nice testing environment
     

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170. Error handling - Nested errors
     Create test “errors.children.servings.errors should exist”
     {
     "code": 400,
     "message": "Validation Failed",
     "errors": {
     "children": {
     "name": [ ],
     "energy": [ ],
     "servings": {
     "errors": [
     "This value should be greater than or equal to 0."
     ]
     }
     }
     }
     

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171. Error handling - HTML errors
     Not the type of error that we want to receive in our API
     

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172. Error handling - HTML errors
     Not the type of error that we want to receive in our API
     
     
     
     
     
     No route found for "GET /recipes" (404 Not Found)
     
     
     
     
     
     
     
     
     
     src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAALYAAAA+CAMAAACxzRGDAAAAUVBMVEX////Ly8yko6WLioxkYmVXVVkwLjLl5eWxsLJKSEzy8vJxcHLY
     2Ni+vb89Oz9XVVh+fH+Yl5n///+xsbLY2Nlxb3KkpKWXlph+fX+LiYy+vr/IZP61AAAAAXRSTlMAQObYZgAABRBJREFUeNrVmtuWoyAQRS1FEEQSzQU7//+hYxUiXsKQZLJW
     M+chsUloN+WhCuguYoKyYqzmvGasKqH4HyRKxndipcgcumH8qViTM7TkUclcwaHmf5XM0eWq4km1KjdqXfMXJHVe1J3hL8lk5fCGv6wmT+o0d87U+XNrk0Y9nfv+7LM6
     ZJH5ZBL6LAbSxQ3Q5FDr22Skr8PQSy4n7isnsQxSX4r6pobhjCHHeDNOKrO3yGmCvZOjV9jmt8ulTdXFKdbKLNh+kOMvBzuVRa4Y7MUsdEUSWQe7xxCfZmcwjHU83LqzFv
     SbJQOXQvptbPnEFoyZtUUGwTeKuLuTHyT1kaP0P6cR01OKvv448gtl61dqZfmJezQmU/t+1R2fJLtBwXV6uWGwB9SZPrn0fKO2WAvQN1PUhHjTom3xgXYTkvlSKHs19Ohsl
     ETq6X3HrXbjt8XbGj9b4Gi+lUAnL6XxQj8Pyk9N4Bt1xUrsLVN/3isYMug8rODMdbgOvoHs8uAb2fcANIAzkKCLYy+AXRpSU8sr1r4P67xhLgPp7vM32zlqt7Bhq2fI1Hwp+VgA
     Nxok59SsGV3oqdUL0YVDMRY7Yg8QLbVUU4NZNoOq5hJHuxEM28Sh/IyUZ8D3reR+yc58EGvOy2U0HQL6G9V+kWyEWHmzaMx6t4o9RhOm/riUiYrzqij4Ptqkn7AaCXqc+F
     47m04ahfde7YIz8RHEBN6BdV
     

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173. Error handling - HTML errors
     We can use the Symfony Crawler to return something nicer
     
     
     
     
     
     No route found for "GET /recipes" (404 Not Found)
     
     
     
     
     
     
     
     
     
     src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAALYAAAA+CAMAAACxzRGDAAAAUVBMVEX////Ly8yko6WLioxkYmVXVVkwLjLl5eWxsLJKSEzy8vJxcHLY
     2Ni+vb89Oz9XVVh+fH+Yl5n///+xsbLY2Nlxb3KkpKWXlph+fX+LiYy+vr/IZP61AAAAAXRSTlMAQObYZgAABRBJREFUeNrVmtuWoyAQRS1FEEQSzQU7//+hYxUiXsKQZLJW
     M+chsUloN+WhCuguYoKyYqzmvGasKqH4HyRKxndipcgcumH8qViTM7TkUclcwaHmf5XM0eWq4km1KjdqXfMXJHVe1J3hL8lk5fCGv6wmT+o0d87U+XNrk0Y9nfv+7LM6
     ZJH5ZBL6LAbSxQ3Q5FDr22Skr8PQSy4n7isnsQxSX4r6pobhjCHHeDNOKrO3yGmCvZOjV9jmt8ulTdXFKdbKLNh+kOMvBzuVRa4Y7MUsdEUSWQe7xxCfZmcwjHU83LqzFv
     SbJQOXQvptbPnEFoyZtUUGwTeKuLuTHyT1kaP0P6cR01OKvv448gtl61dqZfmJezQmU/t+1R2fJLtBwXV6uWGwB9SZPrn0fKO2WAvQN1PUhHjTom3xgXYTkvlSKHs19Ohsl
     ETq6X3HrXbjt8XbGj9b4Gi+lUAnL6XxQj8Pyk9N4Bt1xUrsLVN/3isYMug8rODMdbgOvoHs8uAb2fcANIAzkKCLYy+AXRpSU8sr1r4P67xhLgPp7vM32zlqt7Bhq2fI1Hwp+VgA
     Nxok59SsGV3oqdUL0YVDMRY7Yg8QLbVUU4NZNoOq5hJHuxEM28Sh/IyUZ8D3reR+yc58EGvOy2U0HQL6G9V+kWyEWHmzaMx6t4o9RhOm/riUiYrzqij4Ptqkn7AaCXqc+F
     47m04ahfde7YIz8RHEBN6BdV
     This is what we want
     

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174. Testing, some tips
     Postman, easy to set-up
     Guzzle + PHPUnit, your bread and butter
     Very important to handle errors properly
     Isolated DB for testing (can use SQlite)
     Invest some time in setting up a nice testing environment
     

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175. Testing, some tips
     Postman, easy to set-up
     Guzzle + PHPUnit, your bread and butter
     Very important to handle errors properly
     Isolated DB for testing (can use SQlite)
     Set up proper fixtures (Alice & Faker are nice tools)
     Invest some time in setting up a nice testing environment
     

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176. Fixtures with Alice & Faker
     AppBundle\Entity\Recipe:
     recipe1:
     name: Spanish omelette
     energy: 500
     servings: 4
     recipe{2..20}:
     name:
     energy:
     servings:
     

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177. Fixtures with Alice & Faker
     AppBundle\Entity\Recipe:
     recipe1:
     name: Spanish omelette
     energy: 500
     servings: 4
     recipe{2..20}:
     name:
     energy:
     servings:
     Known values, that
     we may want to use
     in some test
     

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178. Fixtures with Alice & Faker
     AppBundle\Entity\Recipe:
     recipe1:
     name: Spanish omelette
     energy: 500
     servings: 4
     recipe{2..20}:
     name:
     energy:
     servings:
     https://github.com/hautelook/AliceBundle
     https://github.com/fzaninotto/Faker
     Known values, that
     we may want to use
     in some test
     Values created with
     generators
     Many generators available:
     

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179. V. USES FOR YOUR API
     

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180. Uses for an API
     Api serves content to Mobile/Rich web apps/…
     

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181. Uses for an API
     Api serves content to Mobile/Rich web apps/…
     Abstract parts of a monolith into isolated services
     

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182. Uses for an API
     Api serves content to Mobile/Rich web apps/…
     Abstract parts of a monolith into isolated services
     Undertake a migration
     

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183. Migrations - Option 1
     

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184. Migrations - Option 1
     We replace functionalities, one route at a time
     

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185. Migrations - Option 1
     We replace functionalities, one route at a time
     

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186. Migrations - Option 1
     

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187. Migrations - Option 1
     https://speakerdeck.com/hhamon/bringing-symfony-components-into-your-legacy-code
     

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188. Migrations - Option 1
     https://speakerdeck.com/hhamon/bringing-symfony-components-into-your-legacy-code
     Good idea when the team
     feels very comfortable
     with the new framework
     

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189. Migrations - Option 2
     

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190. Migrations - Option 2
     Old system replace its code with calls to new Symfony API
     

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191. Migrations - Option 2
     Good idea when team knows legacy code very well
     

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192. Migrations - Option 2
     Good idea when team knows legacy code very well
     

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193. VI. FINAL THOUGHTS
     

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194. Summarizing
     Whatever the choices you make building your API:
     - Be consistent
     - Take profit of using a common language
     REST and Symfony Components make that easy
     - They fit well together, both built around HTTP
     - A few Components provide a lot
     - You can consider using the full framework if you want more
     Make sure that you set up a proper test environment
     

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195. View Slide

196. https://github.com/VictoriaQ/sonatademo
     @vicqr
     victoria@limenius.com
     Training, consulting and
     development
     https://github.com/VictoriaQ/rest-symfony-components
     @vicqr
     victoria@limenius.com
     Thanks!
     

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