Server Side Swift and GraphQL: A Match Made In Heaven Or Hell? - Deep Dish Swift, Chicago IL, May 2023

I like server side Swift. I also like GraphQL. What happens when you try to put them together? Am I getting chocolate in my peanut butter, or am I creating a monster?

This talk walks through some of the very basics of servers and how GraphQL works, all the way up to running live GraphQL queries on a Vapor server.

Repo: https://github.com/designatednerd/MoveItMoveIt/

Recording: ✨Coming soon! ✨

Transcript

1. SERVER-SIDE SWIFT AND GRAPHQL:
   A MATCH MADE IN
   !
   HEAVEN OR HELL ?
   DEEP DISH SWIFT | CHICAGO, IL | MAY 2023
   ELLEN SHAPIRO | MASTODON.SOCIAL/@DESIGNATEDNERD | PIXITEAPPS.COM
   

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2. FULL
   !
   DISCLOSURE
   @DesignatedNerd@mastodon.social
   

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5. https://www.flickr.com/photos/fwooper7/9650957891
   

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6. SOME DEFINITIONS
   @DesignatedNerd@mastodon.social
   

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7. "Docker is a container
   virtualization platform that
   builds on tools like Virtual Box!"
   @DesignatedNerd@mastodon.social
   

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9. SOME BASIC DEFINITIONS
   @DesignatedNerd@mastodon.social
   

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10. SOME BASIC DEFINITIONS
    FOR A LOT OF APPS
    @DesignatedNerd@mastodon.social
    

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11. YOUR APP'S DATA
    @DesignatedNerd@mastodon.social
    

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12. YOUR APP'S DATA
    THE INFORMATION YOU WANT TO STORE, MANIPULATE AND/OR DISPLAY
    @DesignatedNerd@mastodon.social
    

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13. THE SERVER
    @DesignatedNerd@mastodon.social
    

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14. THE SERVER
    THE PLACE WHERE THE CANONICAL VERSION OF YOUR DATA LIVES
    @DesignatedNerd@mastodon.social
    

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15. THE SERVER
    THE PLACE WHERE THE CANONICAL VERSION OF YOUR DATA LIVES
    (Eventually)
    

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16. THE SERVER
    > Some way to store data
    @DesignatedNerd@mastodon.social
    

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17. THE SERVER
    > Some way to store data
    > Some way to fetch data from storage
    @DesignatedNerd@mastodon.social
    

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18. THE SERVER
    > Some way to store data
    > Some way to fetch data from storage
    > Some way to receive requests for data
    @DesignatedNerd@mastodon.social
    

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19. THE SERVER
    > Some way to store data
    > Some way to fetch data from storage
    > Some way to receive requests for data
    > Some way to return responses for requested data
    @DesignatedNerd@mastodon.social
    

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20. THE SERVER
    > Some way to store data
    > Some way to fetch data from storage
    > Some way to receive requests for data
    > Some way to return responses for requested data
    > Some security mechanisms
    @DesignatedNerd@mastodon.social
    

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21. THE SERVER
    @DesignatedNerd@mastodon.social
    

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22. SERVER-SIDE SWIFT
    @DesignatedNerd@mastodon.social
    

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23. SERVER-SIDE SWIFT
    INFRASTRUCTURE TO BUILD AND RUN THE SERVER IN SWIFT
    @DesignatedNerd@mastodon.social
    

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25. VAPOR
    @DesignatedNerd@mastodon.social
    

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26. VAPOR
    A SWIFT LIBRARY FOR RUNNING YOUR SERVER
    @DesignatedNerd@mastodon.social
    

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27. FLUENT
    @DesignatedNerd@mastodon.social
    

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28. FLUENT
    A SWIFT ADAPTER FOR TALKING TO MULTIPLE DATA STORAGE TYPES
    @DesignatedNerd@mastodon.social
    

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29. THE SERVER
    > Some way to store data
    > Some way to fetch data from storage
    > Some way to receive requests for data
    > Some way to return responses for requested data
    > Some security mechanisms
    @DesignatedNerd@mastodon.social
    

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30. THE SERVER
    > Some way to store data (Fluent)
    > Some way to fetch data from storage (Fluent)
    > Some way to receive requests for data
    > Some way to return responses for requested data
    > Some security mechanisms
    @DesignatedNerd@mastodon.social
    

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31. THE SERVER
    > Some way to store data (Fluent)
    > Some way to fetch data from storage (Fluent)
    > Some way to receive requests for data (Vapor)
    > Some way to return responses for requested data
    (Vapor)
    > Some security mechanisms (mostly Vapor)
    @DesignatedNerd@mastodon.social
    

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32. A CLIENT
    @DesignatedNerd@mastodon.social
    

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33. A CLIENT
    A THING THAT INTERACTS WITH DATA FROM YOUR SERVER
    @DesignatedNerd@mastodon.social
    

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34. A CLIENT
    > Requests data from the server
    @DesignatedNerd@mastodon.social
    

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35. A CLIENT
    > Requests data from the server
    > Processes and displays data from the server
    @DesignatedNerd@mastodon.social
    

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36. A CLIENT
    > Requests data from the server
    > Processes and displays data from the server
    > Processes and displays user input
    @DesignatedNerd@mastodon.social
    

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37. A CLIENT
    > Requests data from the server
    > Processes and displays data from the server
    > Processes and displays user input
    > Sends updated data to the server
    @DesignatedNerd@mastodon.social
    

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38. A CLIENT
    @DesignatedNerd@mastodon.social
    

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39. EXAMPLES OF CLIENTS
    > Website
    @DesignatedNerd@mastodon.social
    

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40. EXAMPLES OF CLIENTS
    > Website
    > iOS App
    > Android App
    @DesignatedNerd@mastodon.social
    

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41. EXAMPLES OF CLIENTS
    > Website
    > iOS App
    > Android App
    > Another server not owned by you
    @DesignatedNerd@mastodon.social
    

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42. EXAMPLES OF CLIENTS
    > Website
    > iOS App
    > Android App
    > Another server not owned by you
    > An IoT Device
    @DesignatedNerd@mastodon.social
    

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43. Photo via https://flickr.com/photos/ockam/16307930064
    

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44. THE PUBLIC API
    @DesignatedNerd@mastodon.social
    

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45. THE PUBLIC API
    THE DEFINITION OF HOW THE CLIENT AND SERVER CAN TALK TO EACH OTHER
    @DesignatedNerd@mastodon.social
    

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46. APPLICATION PROGRAMMING
    INTERFACE
    @DesignatedNerd@mastodon.social
    

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47. INTERFACE
    @DesignatedNerd@mastodon.social
    

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48. REST
    @DesignatedNerd@mastodon.social
    

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49. REST
    REPRESENTATIONAL STATE TRANSFER
    @DesignatedNerd@mastodon.social
    

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50. api/user/1
    {
    "id": "1",
    "name": "Bart Simpson"
    "age": "10"
    "family_member_ids": [ "2", "3", "4", "5" ]
    }
    @DesignatedNerd@mastodon.social
    

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51. api/user/1:
    {
    "id": "1",
    "name": "Bart Simpson"
    "age": "10"
    "family_members": [
    {
    "id": "2",
    "name": "Lisa Simpson",
    "age": 8
    },
    {
    "id": 3",
    "name": "Homer Simpson",
    "age": 39
    },
    {
    "id": "4",
    "name": "Marge Simpson",
    "age": 39
    },
    {
    "id": "5",
    "name": "Maggie Simpson",
    "age": 1
    }
    ]
    }
    @DesignatedNerd@mastodon.social
    

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52. @DesignatedNerd@mastodon.social
    

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53. View Slide

54. Photo via https://flickr.com/photos/johnath/7356295658
    

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55. VAPOR
    HAS BUILT IN REST SUPPORT
    @DesignatedNerd@mastodon.social
    

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56. GRAPHQL
    @DesignatedNerd@mastodon.social
    

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57. GRAPHQL
    A TYPE OF PUBLIC API THAT ALLOWS CLIENTS TO REQUEST SPECIFIC FIELDS FROM THE SERVER
    @DesignatedNerd@mastodon.social
    

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58. Source: https://flickr.com/photos/acaben/2816139/
    

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60. WHAT CAN I ASK FOR?
    HOW CAN I ASK FOR IT?
    @DesignatedNerd@mastodon.social
    

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61. REST: THERE IS NO STANDARD WAY
    @DesignatedNerd@mastodon.social
    

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62. GOOD: OPENAPI (FKA SWAGGER)
    @DesignatedNerd@mastodon.social
    

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63. GOOD: OPENAPI (FKA SWAGGER)
    @DesignatedNerd@mastodon.social
    

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64. LESS GOOD...
    @DesignatedNerd@mastodon.social
    

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65. "Oh no, we don't have any place
    where all the HTTP endpoints are
    written down. Just grep the
    codebase of the monolith, that
    should get you what you need."
    @DesignatedNerd@mastodon.social
    

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66. "Oh no, we don't have any place
    where all the HTTP endpoints are
    written down. Just grep the
    codebase of the monolith, that
    should get you what you need."
    (An actual thing someone told me to do the first week of a new job)
    

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67. !
    @DesignatedNerd@mastodon.social
    

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68. THE GRAPHQL SCHEMA
    @DesignatedNerd@mastodon.social
    

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69. THE GRAPHQL SCHEMA
    A CONTRACT OF WHAT CAN BE REQUESTED, WHAT WILL BE RETURNED, AND HOW
    @DesignatedNerd@mastodon.social
    

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70. IN THE SCHEMA
    > Scalars
    @DesignatedNerd@mastodon.social
    

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71. IN THE SCHEMA
    > Scalars
    > Custom Types
    @DesignatedNerd@mastodon.social
    

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72. IN THE SCHEMA
    > Scalars
    > Custom Types
    > Fields/Properties
    @DesignatedNerd@mastodon.social
    

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73. IN THE SCHEMA
    > Scalars
    > Custom Types
    > Fields/Properties
    > Relationships (inferred)
    @DesignatedNerd@mastodon.social
    

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74. A NOTE ABOUT GRAPHQL
    ❓
    OPTIONALITY
    @DesignatedNerd@mastodon.social
    

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75. is Optional Swift Type GraphQL Type
    @DesignatedNerd@mastodon.social
    

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76. is Optional Swift Type GraphQL Type
    No
    @DesignatedNerd@mastodon.social
    

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77. is Optional Swift Type GraphQL Type
    No String
    @DesignatedNerd@mastodon.social
    

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78. is Optional Swift Type GraphQL Type
    No String String!
    @DesignatedNerd@mastodon.social
    

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79. !
    @DesignatedNerd@mastodon.social
    

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80. GRAPHQL TYPES ARE
    NULLABLE BY DEFAULT
    @DesignatedNerd@mastodon.social
    

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81. is Optional Swift Type GraphQL Type
    No String String!
    @DesignatedNerd@mastodon.social
    

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82. is Optional Swift Type GraphQL Type
    No String String!
    Yes
    @DesignatedNerd@mastodon.social
    

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83. is Optional Swift Type GraphQL Type
    No String String!
    Yes String?
    @DesignatedNerd@mastodon.social
    

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84. is Optional Swift Type GraphQL Type
    No String String!
    Yes String? String
    @DesignatedNerd@mastodon.social
    

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85. A GRAPHQL OPERATION
    @DesignatedNerd@mastodon.social
    

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86. A GRAPHQL OPERATION
    A DEFINITION OF A REQUEST TO FETCH, CHANGE, OR LISTEN TO CHANGES FOR YOUR DATA
    @DesignatedNerd@mastodon.social
    

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87. OPERATIONS
    > Query: I'd like some info, please
    @DesignatedNerd@mastodon.social
    

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88. OPERATIONS
    > Query: I'd like some info, please
    > Mutation: I'd like to make a change
    @DesignatedNerd@mastodon.social
    

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89. OPERATIONS
    > Query: I'd like some info, please
    > Mutation: I'd like to make a change
    > Subscription: Keep me up to date on changes
    @DesignatedNerd@mastodon.social
    

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90. OPERATIONS
    > Query: I'd like some info, please
    > Mutation: I'd like to make a change
    > Subscription: Keep me up to date on changes
    @DesignatedNerd@mastodon.social
    

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91. @DesignatedNerd@mastodon.social
    

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92. HOW DO WE COMBINE
    VAPOR AND GRAPHQL?
    @DesignatedNerd@mastodon.social
    

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93. Photo: https://flickr.com/photos/daveseven/6138666188
    

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94. `HTTPS://GITHUB.COM/DESIGNATEDNERD/
    MOVEITMOVEIT
    @DesignatedNerd@mastodon.social
    

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95. GRAPHQLKIT
    @DesignatedNerd@mastodon.social
    

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96. dependencies: [
    .package(url: "https://github.com/alexsteinerde/graphql-kit.git",
    from: "2.0.0"),
    ],
    @DesignatedNerd@mastodon.social
    

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97. @DesignatedNerd@mastodon.social
    

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98. WHAT IS ALL THIS?
    @DesignatedNerd@mastodon.social
    

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99. Source: https://flickr.com/photos/xurble/378943497
    

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100. Source: https://flickr.com/photos/xurble/378943497
     

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101. Source: https://flickr.com/photos/xurble/378943497
     

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102. HIGHEST LEVEL
     ⬇
     LOWEST LEVEL
     @DesignatedNerd@mastodon.social
     

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103. GRAPHQLKIT
     @DesignatedNerd@mastodon.social
     

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104. GRAPHQLKIT
     EASY GRAPHQL INTEGRATION WITH A VAPOR SERVER
     @DesignatedNerd@mastodon.social
     

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105. GRAPHITI
     @DesignatedNerd@mastodon.social
     

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106. GRAPHITI
     HELPS YOU BUILD A GRAPHQL SCHEMA IN SWIFT
     @DesignatedNerd@mastodon.social
     

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107. GRAPHQLSWIFT/GRAPHQL
     @DesignatedNerd@mastodon.social
     

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108. GRAPHQLSWIFT/GRAPHQL
     THE ABSOLUTE BASE HANDLING OF GQL IN SWIFT
     @DesignatedNerd@mastodon.social
     

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109. VAPOR + FLUENT
     @DesignatedNerd@mastodon.social
     

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110. VAPOR + FLUENT
     (YOU KNOW THESE TWO ALREADY)
     @DesignatedNerd@mastodon.social
     

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112. // These all get pulled automatically with GraphQL kit, but you need
     // to explicitly declare them as dependencies to use them directly.
     .package(url: "https://github.com/vapor/vapor.git",
     .upToNextMajor(from: "4.0.0")),
     .package(url: "https://github.com/vapor/fluent.git",
     .upToNextMajor(from: "4.0.0")),
     .package(url: "https://github.com/vapor/fluent-sqlite-driver.git",
     .upToNextMajor(from: "4.0.0")),
     .package(url: "https://github.com/GraphQLSwift/Graphiti",
     .upToNextMinor(from: "0.26.0")),
     @DesignatedNerd@mastodon.social
     

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113. .target(name: "App",
     dependencies: [
     .product(name: "Fluent", package: "fluent"),
     .product(name: "FluentSQLiteDriver", package: "fluent-sqlite-driver"),
     .product(name: "Vapor", package: "vapor"),
     .product(name: "GraphQLKit", package: "graphql-kit"),
     .product(name: "GraphiQLVapor", package: "graphiql-vapor"),
     ]),
     @DesignatedNerd@mastodon.social
     

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114. LET'S BUILD
     A GRAPHQL API!
     @DesignatedNerd@mastodon.social
     

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115. BACKING OBJECT CREATION
     @DesignatedNerd@mastodon.social
     

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116. BACKING OBJECT CREATION:
     THE SAME AS FOR REST
     @DesignatedNerd@mastodon.social
     

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117. final class User: Model, Content {
     static var schema = "users"
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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118. final class User: Model, Content {
     static var schema = "users"
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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120. final class User: Model, Content {
     static var schema = "users"
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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121. final class User: Model, Content {
     static var schema = "users"
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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122. final class User: Model, Content {
     static var schema = "users"
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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123. final class User: Model, Content {
     static var schema = "users"
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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124. final class User: Model, Content {
     static var schema = "users"
     enum DatabaseKeys: String {
     case email
     case name
     case hashedPassword
     }
     @ID(key: .id)
     var id: UUID?
     @Field(key: "email")
     var email: String
     @Field(key: "name")
     var name: String
     @Field(key: "hashedPassword")
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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125. final class User: Model, Content {
     static var schema = "users"
     enum DatabaseKeys: String {
     case email
     case name
     case hashedPassword
     }
     @ID(key: .id)
     var id: UUID?
     @Field(key: DatabaseKeys.email.fieldKey)
     var email: String
     @Field(key: DatabaseKeys.name.fieldKey)
     var name: String
     @Field(key: DatabaseKeys.hashedPassword.fieldKey)
     var hashedPassword: String
     @Children(for: \.$user)
     var moves: [Move]
     // ...
     }
     @DesignatedNerd@mastodon.social
     

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126. CREATING A CONFIG
     @DesignatedNerd@mastodon.social
     

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127. // configures your application
     public func configure(_ app: Application) throws {
     app.databases.use(.sqlite(.memory), as: .sqlite)
     // Create the appropriate migrations
     app.migrations.add(User.Migration())
     app.migrations.add(Move.Migration())
     try app.autoMigrate().wait()
     // Register the schema and its resolver.
     // TODO
     }
     @DesignatedNerd@mastodon.social
     

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128. // configures your application
     public func configure(_ app: Application) throws {
     app.databases.use(.sqlite(.memory), as: .sqlite)
     // Create the appropriate migrations
     app.migrations.add(User.Migration())
     app.migrations.add(Move.Migration())
     try app.autoMigrate().wait()
     // Register the schema and its resolver.
     // TODO
     }
     @DesignatedNerd@mastodon.social
     

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129. // configures your application
     public func configure(_ app: Application) throws {
     app.databases.use(.sqlite(.memory), as: .sqlite)
     // Create the appropriate migrations
     app.migrations.add(User.Migration())
     app.migrations.add(Move.Migration())
     try app.autoMigrate().wait()
     // Register the schema and its resolver.
     // TODO
     }
     @DesignatedNerd@mastodon.social
     

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130. RESOLVER
     @DesignatedNerd@mastodon.social
     

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131. RESOLVER
     FUNCTION TO GET DATA AND GIVE IT TO GQL
     @DesignatedNerd@mastodon.social
     

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132. BARE-BONES RESOLVER
     class GraphQLResolver {
     }
     @DesignatedNerd@mastodon.social
     

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133. DECLARING YOUR SCHEMA
     @DesignatedNerd@mastodon.social
     

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134. let movingSchema = try! Schema {
     Type(User.self) {
     Field("id", at: \.id)
     Field("email", at: \.email)
     Field("name", at: \.name)
     }
     }
     @DesignatedNerd@mastodon.social
     

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135. let movingSchema = try! Schema {
     Type(User.self) {
     Field("id", at: \.id)
     Field("email", at: \.email)
     Field("name", at: \.name)
     }
     }
     @DesignatedNerd@mastodon.social
     

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136. let movingSchema = try! Schema {
     Type(User.self) {
     Field("id", at: \.id)
     Field("email", at: \.email)
     Field("name", at: \.name)
     }
     }
     @DesignatedNerd@mastodon.social
     

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137. View Slide

138. // configure.swift
     // Register the schema and its resolver.
     app.register(graphQLSchema: movingSchema,
     withResolver: GraphQLResolver())
     @DesignatedNerd@mastodon.social
     

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139. @DesignatedNerd@mastodon.social
     

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140. "YOU FORGOT TO DECLARE THIS TYPE
     IN THE SCHEMA, YA DING DONG"
     @DesignatedNerd@mastodon.social
     

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141. let movingSchema = try! Schema {
     Scalar(UUID.self)
     Type(User.self) {
     Field("id", at: \.id)
     Field("email", at: \.email)
     Field("name", at: \.name)
     }
     }
     @DesignatedNerd@mastodon.social
     

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142. !
     @DesignatedNerd@mastodon.social
     

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143. let movingSchema = try! Schema {
     Scalar(UUID.self)
     Type(User.self) {
     Field("id", at: \.id)
     Field("email", at: \.email)
     Field("name", at: \.name)
     }
     }
     @DesignatedNerd@mastodon.social
     

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144. @DesignatedNerd@mastodon.social
     

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145. @DesignatedNerd@mastodon.social
     

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146. let movingSchema = try! Schema {
     Scalar(UUID.self)
     Type(User.self) {
     Field("id", at: \.id, as: UUID.self)
     Field("email", at: \.email)
     Field("name", at: \.name)
     }
     }
     @DesignatedNerd@mastodon.social
     

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147. @DesignatedNerd@mastodon.social
     

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148. @DesignatedNerd@mastodon.social
     

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149. !❗
     @DesignatedNerd@mastodon.social
     

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150. HANDLING OPERATIONS
     @DesignatedNerd@mastodon.social
     

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151. Mutation {
     Field("createUser", at: GraphQLResolver.createUser) {
     Argument("name", at: \.name)
     Argument("email", at: \.email)
     Argument("password", at: \.password)
     }
     }
     @DesignatedNerd@mastodon.social
     

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152. Mutation {
     Field("createUser", at: GraphQLResolver.createUser) {
     Argument("name", at: \.name)
     Argument("email", at: \.email)
     Argument("password", at: \.password)
     }
     }
     @DesignatedNerd@mastodon.social
     

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153. Mutation {
     Field("createUser", at: GraphQLResolver.createUser) {
     Argument("name", at: \.name)
     Argument("email", at: \.email)
     Argument("password", at: \.password)
     }
     }
     @DesignatedNerd@mastodon.social
     

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154. struct UserCreateArguments: Codable {
     let name: String
     let email: String
     let password: String
     }
     extension GraphQLResolver {
     func createUser(request: Request,
     arguments: UserCreateArguments) throws -> EventLoopFuture {
     let user = try User(email: arguments.email,
     password: arguments.password,
     name: arguments.name)
     return user.create(on: request.db).map { user }
     }
     }
     @DesignatedNerd@mastodon.social
     

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155. struct UserCreateArguments: Codable {
     let name: String
     let email: String
     let password: String
     }
     extension GraphQLResolver {
     func createUser(request: Request,
     arguments: UserCreateArguments) throws -> EventLoopFuture {
     let user = try User(email: arguments.email,
     password: arguments.password,
     name: arguments.name)
     return user.create(on: request.db).map { user }
     }
     }
     @DesignatedNerd@mastodon.social
     

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156. struct UserCreateArguments: Codable {
     let name: String
     let email: String
     let password: String
     }
     extension GraphQLResolver {
     func createUser(request: Request,
     arguments: UserCreateArguments) throws -> EventLoopFuture {
     let user = try User(email: arguments.email,
     password: arguments.password,
     name: arguments.name)
     return user.create(on: request.db).map { user }
     }
     }
     @DesignatedNerd@mastodon.social
     

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157. Mutation {
     Field("createUser", at: GraphQLResolver.createUser) {
     Argument("name", at: \.name)
     Argument("email", at: \.email)
     Argument("password", at: \.password)
     }
     }
     @DesignatedNerd@mastodon.social
     

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158. Mutation {
     Field("createUser", at: GraphQLResolver.createUser) {
     Argument("name", at: \.name)
     Argument("email", at: \.email)
     Argument("password", at: \.password)
     }
     }
     @DesignatedNerd@mastodon.social
     

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159. TRYING IT OUT
     @DesignatedNerd@mastodon.social
     

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160. EASIEST: GRAPHIQL
     @DesignatedNerd@mastodon.social
     

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161. // Something to help visualize and test your schema and operations
     .package(url: "https://github.com/alexsteinerde/graphiql-vapor.git",
     .upToNextMajor(from: "2.0.0")),
     @DesignatedNerd@mastodon.social
     

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162. .target(name: "App",
     dependencies: [
     // (existing dependencies)
     .product(name: "GraphiQLVapor", package: "graphiql-vapor"),
     ]),
     @DesignatedNerd@mastodon.social
     

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163. import GraphiQLVapor
     public func configure(_ app: Application) throws {
     //... (stuff you already saw)
     // Enable GraphiQL web page for built-in goodness
     if !app.environment.isRelease {
     app.enableGraphiQL()
     }
     }
     @DesignatedNerd@mastodon.social
     

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164. View Slide

165. @DesignatedNerd@mastodon.social
     

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166. View Slide

167. @DesignatedNerd@mastodon.social
     

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168. @DesignatedNerd@mastodon.social
     

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169. APOLLO STUDIO
     HTTPS://STUDIO.APOLLOGRAPHQL.COM/SANDBOX/EXPLORER
     @DesignatedNerd@mastodon.social
     

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170. @DesignatedNerd@mastodon.social
     

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171. @DesignatedNerd@mastodon.social
     

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172. @DesignatedNerd@mastodon.social
     

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173. View Slide

174. @DesignatedNerd@mastodon.social
     

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175. CORS: CROSS-ORIGIN
     RESOURCE SHARING
     @DesignatedNerd@mastodon.social
     

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176. CORS: CROSS-ORIGIN
     RESOURCE SHARING
     (DISABLED BY DEFAULT IN VAPOR)
     @DesignatedNerd@mastodon.social
     

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177. let corsConfiguration = CORSMiddleware.Configuration(
     allowedOrigin: .custom("https://studio.apollographql.com"),
     allowedMethods: [.POST],
     allowedHeaders: [
     .accept,
     .contentType,
     .accessControlAllowOrigin,
     .origin
     ]
     )
     let cors = CORSMiddleware(configuration: corsConfiguration)
     app.middleware.use(cors)
     @DesignatedNerd@mastodon.social
     

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178. !
     PITFALLS
     @DesignatedNerd@mastodon.social
     

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179. LOTS OF FIGHTING
     WITH THE COMPILER
     @DesignatedNerd@mastodon.social
     

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180. View Slide

181. THERE CAN ONLY BE ONE
     (RESOLVER CLASS)
     @DesignatedNerd@mastodon.social
     

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182. class MoveResolver {
     private let userResolver = UserResolver()
     // MARK: - Pass-Through Methods
     func createUser(request: Request,
     arguments: UserCreateArguments) throws
     -> EventLoopFuture {
     try userResolver.createUser(request: request,
     arguments: arguments)
     }
     //...
     }
     @DesignatedNerd@mastodon.social
     

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183. GraphQLResolver+Moves.swift
     class GraphQLResolver {
     func createMove(request: Request,
     arguments: CreateMoveArguments) -> EventLoopFuture {
     //...
     }
     }
     GraphQLResolver+Users.swift
     extension GraphQLResolver
     func createUser(request: Request,
     arguments: UserCreateArguments) throws -> EventLoopFuture {
     //...
     }
     }
     @DesignatedNerd@mastodon.social
     

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184. DATA LOADING INEFFICIENCIES
     @DesignatedNerd@mastodon.social
     

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185. DATA LOADER
     @DesignatedNerd@mastodon.social
     

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186. 404 DATA LOADER NOT FOUND
     @DesignatedNerd@mastodon.social
     

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187. @DesignatedNerd@mastodon.social
     

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188. THE VERDICT:
     @DesignatedNerd@mastodon.social
     

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189. THE VERDICT:
     IT DEPENDS
     @DesignatedNerd@mastodon.social
     

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190. View Slide

191. THE VERDICTS:
     >
     !
     If you know a lot about both Vapor/Fluent AND GQL
     @DesignatedNerd@mastodon.social
     

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192. THE VERDICTS
     >
     !
     If you know a lot about both Vapor/Fluent AND GQL
     >
     "
     If you know a lot about Vapor/Fluent but not GQL
     @DesignatedNerd@mastodon.social
     

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193. THE VERDICTS
     >
     !
     If you know a lot about both Vapor/Fluent AND GQL
     >
     "
     If you know a lot about Vapor/Fluent but not GQL
     >
     #
     If you know a lot about GQL but not Vapor/Fluent
     @DesignatedNerd@mastodon.social
     

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194. THE VERDICTS
     >
     !
     If you know a lot about both Vapor/Fluent AND GQL
     >
     "
     If you know a lot about Vapor/Fluent but not GQL
     >
     #
     If you know a lot about GQL but not Vapor/Fluent
     >
     $
     If you don't know a lot about either one
     @DesignatedNerd@mastodon.social
     

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195. View Slide

196. OBLIGATORY SUMMARY SLIDE
     @DesignatedNerd@mastodon.social
     

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197. OBLIGATORY SUMMARY SLIDE
     >
     !
     If you know a lot about both Vapor/Fluent AND GQL
     >
     "
     If you know a lot about Vapor/Fluent but not GQL
     >
     #
     If you know a lot about GQL but not Vapor/Fluent
     >
     $
     If you don't know a lot about either one
     @DesignatedNerd@mastodon.social
     

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198. THANK YOU!
     @DesignatedNerd@mastodon.social
     

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199. LINKS!
     > Vapor/Fluent Docs: https://docs.vapor.codes/
     > GraphQLKit: https://github.com/alexsteinerde/
     graphql-kit/
     > (slightly outdated) Tutorial on getting started:
     https://www.kodeco.com/21148796-graphql-
     tutorial-for-server-side-swift-with-vapor-
     getting-started
     @DesignatedNerd@mastodon.social
     

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