Symfony Live 2017 - Serializer

Transcript

1. SymfonyLive
   Paris 2017
   The Serializer
   Component
   

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2. I am Grégoire Pineau
   DevOps @blackfireio / @sensiolabs
   @symfony Core Contributor
   Github / Twitter : @lyrixx
   Hello!
   2
   

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3. 3
   Serialization ?
   

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4. “
   Serialization is the process of translating data
   structures or object state into a format that can
   be stored and reconstructed later in the same or
   another computer environment.
   Adapted from
   en.wikipedia.org/wiki/Serialization
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5. When?
   ◉ To store data in a DB (RDBMS, Redis, Elasticsearch)
   ◉ To send / receive data via an API
   ◉ To send / receive data via messaging system (AMQP)
   ◉ To detect changes in time-varying data
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6. Why?
   ◉ PHP serialize / unserialize functions are powerful but:
   ○ Not interoperable
   ○ Not configurable
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7. Different formats
   ◉ Binary:
   ○ Faster
   ○ Smaller
   ○ Ex: protobuf, Apache Thrift, …
   ◉ Textual
   ○ Human readable / editable
   ○ Ex: CSV, JSON, XML, YAML, ... 7
   

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8. symfony/serializer
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9. History
   

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10. Before symfony 2.7
    ◉ JMSSerializer:
    ○ Had more features
    ○ Had a better integration with others libs
    ○ Was more used
    ◉ Symfony Serializer
    ○ Was not really used
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11. History
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12. Symfony 2.7 & next
    ◉ Tons of new features
    ◉ … and keeps counting
    ◉ Better integration with others lib
    ◉ Simpler than JMSSerializer (?)
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13. Architecture
    

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15. 15
    And Decoders
    Encoders
    

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16. Encoders
    ◉ CsvEncoder
    ◉ JsonEncoder
    ◉ XmlEncoder
    ◉ YamlEncoder
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17. Encoder usage
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18. Decoder usage
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20. 20
    And denormalizers
    Normalizers
    

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21. Normalizers
    AbstractNormalizer, AbstractObjectNormalizer, ArrayDenormalizer,
    ContextAwareDenormalizerInterface,
    ContextAwareNormalizerInterface, CustomNormalizer,
    DataUriNormalizer, DateTimeNormalizer, DenormalizableInterface,
    DenormalizerAwareInterface, DenormalizerAwareTrait,
    DenormalizerInterface, GetSetMethodNormalizer,
    JsonSerializableNormalizer, NormalizableInterface,
    NormalizerAwareInterface, NormalizerAwareTrait, NormalizerInterface,
    ObjectNormalizer, PropertyNormalizer, SerializerAwareNormalizer
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22. Object Normalizers
    GetSetMethodNormalizer Uses getters and setters
    PropertyNormalizer Uses Reflection
    CustomNormalizer Uses $object->normalize();
    ObjectNormalizer Uses PropertyAccess Component
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23. Extra Normalizer
    DateTimeNormalizer Turns DateTime into string
    DataUriNormalizer Turns SplFileInfo into data:uri
    ArrayDenormalizer Denormalizes arrays of objects
    JsonSerializableNormalizer Turns JsonSerializable into a string
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24. Normalizer usage
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25. Denormalizer usage
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27. 27
    And deserializer
    Serializer
    

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28. Serializer
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29. Serializer Usage
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30. Deserializer Usage
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32. symfony/symfony-demo
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33. 33
    https://github.com/symfony/symfony-demo
    

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34. Enable the serializer
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35. Let’s build an API
    on top of
    symfony/demo
    

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36. Create a Controller
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37. Try it
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38. Configuration
    Groups
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39. Groups
    ◉ Choose what property is (de) serialized
    ◉ Could be used:
    ○ For read / write access
    ○ For security (public, connected user, admin user)
    ○ For API versioning
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40. Groups
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41. Tips
    Use the following format for your Groups:
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    GET /posts post_list_read
    GET /posts/12 post_read
    PUT /posts/12 post_write
    GET /posts/12/details post_details_read
    

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42. Groups
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    Context
    

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43. Configuration
    MaxDepth
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44. MaxDepth
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45. Configuration
    NameConverter
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46. NameConverter
    Tweak the name of a property:
    ◉ By default, it uses the property name (CamelCase)
    ◉ Automatically convert to snake_case
    ◉ Rename / Alias some property
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47. Try it again
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48. Add more data ...
    … to the representation
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49. Custom Object
    Normalizer
    ◉ Allow to tweak at PHP level the normalization
    ◉ Be able to add or remove some data:
    ○ Canonical URL
    ○ “Computed” data: the number of post’s comment
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50. PostNormalizer
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51. PostNormalizer
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52. Custom Object
    Normalizer
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53. Try it again
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54. 54
    Circular Reference
    

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55. Circular Reference
    ◉ Example: “Post” has a one-to-many relation
    “Comment”. A “Comment” has a property
    “Post”.
    ◉ By default the serializer will throw an
    exception because of the circular reference
    ◉ But you can implement a Circular Reference
    Handler
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56. Circular Reference
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57. Circular Reference
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58. Circular Reference
    SF 3.3
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59. Circular Reference
    < SF 3.2
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60. Deserialization
    Aka: How to use user data
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61. Create a Controller
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62. Create a Controller
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63. ConstraintViolation
    ListNormalizer
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64. Send invalid data
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65. Send valid data
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66. Deserialization
    Into an Object
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67. Into an Object
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68. Deserialization
    With some relations
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69. Post Object
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70. Enable the property
    info component
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71. Try it!
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72. Solution
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    You need to create a TagDenormalizer to handle
    the situation: search the tag in DB:
    ◉ If exists, uses it
    ◉ If not, create it
    

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73. Deserialization
    Of array
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74. The controller
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75. Summary
    

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77. Summary
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    ◉ Use Groups
    ◉ Create a normalizer for each serialized entity
    ○ Service tag: ‘serializer.normalizer’
    ◉ Create a circular reference handler
    

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78. Any questions ?
    @lyrixx
    Thanks!
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