Introduction to GraphQL

Transcript

1. Introduction to GraphQL

2. GET https://2017.es.pycon.org/speakers/me { "name": "Adrián Matellanes", "roles": [ "Lead API

   Developer", "Málaga Python Organizer" ], "worksAt": "Ebury", "twitter": "@_amatellanes", "github": "github.com/amatellanes" }

3. What’s GraphQL?

4. A programming language

5. A special type of database

6. A library

7. A Query Language for APIs

8. Why GraphQL?

9. Due to the nature of REST

10. REST Problems

11. GET /characters/1 { "name": "Jon Snow" }

12. "url": "http://anapioficeandfire.com/api/characters/583", "name": "Jon Snow", "culture": "Northmen", "born": "In 283

    AC", "titles": [ "Lord Commander of the Night's Watch" ], "aliases": [ "Lord Snow", "Ned Stark's Bastard", "The Snow of Winterfell", "The Bastard of Winterfell", "Lord Crow" ], "allegiances": [ "http://anapioficeandfire.com/api/houses/362" ], "books": [ "http://anapioficeandfire.com/api/books/5" ], "povBooks": [ "http://anapioficeandfire.com/api/books/1", "http://anapioficeandfire.com/api/books/2", "http://anapioficeandfire.com/api/books/3", "http://anapioficeandfire.com/api/books/8"

13. Round Trip and Repeat Trip Times

14. None

15. /episodes/1

16. /episodes/1 /characters/345 /characters/563 /characters/802 /characters/441 /characters/674

17. /episodes/1 /characters/345 /characters/563 /characters/802 /characters/441 /characters/674 /reviews/3512

18. Over/Under Fetching

19. /episodes/1?fields=characters(name,playedBy)

20. /episode_with_all_stuff /episode_with_amazing_pictures /episode_with_stuff_i_need_today /episode_with_stuff_for_mobile_app /episode_with_actors_and_reviews_and_images /episode_with_stuff_for_mobile_app_v2 /episode_with_actors_and_reviews_but_no_images

21. /episode_with_all_stuff /episode_with_amazing_pictures /episode_with_stuff_i_need_today /episode_with_stuff_for_mobile_app /episode_with_stuff_for_mobile_app_v2 /episode_with_actors_and_reviews_and_images /episode_with_actors_and_reviews_but_no_images

22. None

23. https://code.facebook.com/projects/

24. Created July 1, 2015 Updated September 20, 2017 381 Forks

    6,078 Stars 302 Commits 82 Open Issues https://github.com/facebook/graphql
25. None

26. “You will receive what you ask for no more, no

    less.” - Mark Allen
27. None
28. None
29. None
30. None
31. None
32. None
33. None
34. None
35. None
36. None
37. None

38. GraphQL vs. REST

39. REST Model

40. Client /books /characters /houses Databases Services External APIs

41. GraphQL Model

42. Client Databases Services External APIs /graphql/

43. Anatomy of a GraphQL

44. { me { name } }

45. { me { name } } { "me": { "name":

    "Jon Snow" } }

46. Scalar types

47. Int Float String Boolean ID Date enum

48. GraphQL Schema Definition Language

49. type Query { allCharacters: [Character]! character(id: ID!): Character }

50. type Query { allCharacters: [Character]! character(id: ID!): Character } Root

    Type

51. type Query { allCharacters: [Character]! character(id: ID!): Character } Root

    Fields

52. type Query { allCharacters: [Character]! character(id: ID!): Character } Arguments

53. type Query { allCharacters: [Character]! character(id: ID!): Character } Return

    Types

54. type Character { name: String! house: House! } type House

    { name: String! words: String! members: [Character]! }

55. type Character { name: String! house: House! } type House

    { name: String! words: String! members: [Character]! } Object Type

56. type Character { name: String! house: House! } type House

    { name: String! words: String! members: [Character]! } Fields

57. type Character { name: String! house: House! } type House

    { name: String! words: String! members: [Character]! } Return Types

58. Queries for fetching data from the server

59. query CharactersNameAndHouse { allCharacters { name house { words }

    } }

60. query CharactersNameAndHouse { allCharacters { name house { words }

    } } Operation Type

61. query CharactersNameAndHouse { allCharacters { name house { words }

    } } Operation Name

62. query CharactersNameAndHouse { allCharacters { name house { words }

    } } Selection Set

63. query CharactersNameAndHouse { allCharacters { name house { words }

    } } Fields

64. query CharactersNameAndHouse { allCharacters { name house { words }

    } } { "data": { "allCharacters": [ { "name": "Daenerys Targaryen", "house": { "words": "Fire and Blood" } }, { "name": "Jon Snow", "house": { "words": "Winter Is Coming" } } ] } }

65. query { character(name: "Hodor") { name house { words }

    } } Arguments

66. query CharacterByName($name: String!) { character(name: $name) { name } }

    { "name": "Hodor" } Variables

67. query { character(name: "Hodor") { ...CharacterFragment } } fragment CharacterFragment

    on Character { name house { words } } Fragments

68. { character(name: "Hodor") { ... on Character { name house

    { words } } } } Inline Fragments

69. Mutations for manipulating data and fetch the updated result

70. type Mutation { createCharacter(name: String!): Character }

71. mutation CharacterMutation { createCharacter(name: "Sansa Stark") { name } }

    { "data": { "createCharacter": { "name": "Sansa Stark" } } }

72. Subscriptions for real-time updates

73. type Subscription { newCharacter: Character! }

74. subscription NewCharacterSubscription { newCharacter { name } } { "data":

    { "newCharacter": { "name": "Tyrion Lannister" } } }

75. Query Execution

76. { getHouse(id: 5) { name words members { name }

    } }

77. name words members getHouse(id: 5) { name, words, members }

    [ { name }, { name } ] name name

78. QUERY name words members getHouse(id: 5) { name, words, members

    } [ { name }, { name } ] name name

79. QUERY getHouse(id: 5) { name, words, members } HOUSE name

    words members [ { name }, { name } ] name name

80. QUERY getHouse(id: 5) { name, words, members } HOUSE name

    words members [ { name }, { name } ] CHARACTER name name

81. Clients with Super Powers

82. Introspection Queries

83. { "data": { "__type": { "name": "Book", "kind": "OBJECT", "fields":

    [ { "name": "title", "type": { "name": "String" } } ] } } } { __type(name: "Book") { name kind fields { name type { name } } } }
84. None

85. GraphiQL

86. None

87. Graphene GraphQL framework for Python

88. Created September 24, 2015 Updated September 20, 2017 229 Forks

    2,356 Stars 1,219 Commits 87 Open Issues https://github.com/graphql-python/graphene
89. None
90. None

91. "It’s important to understand that it isn’t all or nothing.

    GraphQL is in our future, but it isn’t our exclusive future."

92. Thank you!