GraphQL & Relay － 串起前後端世界的橋樑

隨著前端互動體驗日益受到重視，前端與 app 設計者們無不希望能做出Ｑ彈滑順的使用介面擄獲使用者的心。但對資料導向應用程式的開發者而言，要保持實現各種設計的的靈活度便成了一大難題，經常需要實作資料的快取、分頁、快速回應變動、即時更新更是一份苦差事。GraphQL 是 Facebook 推出的資料查詢語言，佐以 Relay 這個為 React 打造的 data fetching framework，我們就可以告別前後端如何交換資料的頭痛問題，將心力放在打造出令人愛不釋手的 React、React Native app 上。

Video: https://youtu.be/r-ODwIcQeCM
Same thing on SlideShare: https://www.slideshare.net/pokaichang72/graphql-relay-78728604

1. ! # @zetavg
 fb.me/pokaichang72 串串起前後端資料的橋樑
 GraphQL 
 & Relay
2. Q: 這個 app 需要多少 API Endpoints?
3. Ans: 4 GET /api/todos.json POST /api/todos.json PATCH /api/todos/id.json DELETE /api/todos/id.json
4. Q: 那這個 app 需要多少 API Endpoints 呢?
5. /api/v1/posts.json /api/v2/posts.json /api/v3/posts.json /api/v4/posts.json /api/v65535/posts.json ⋯⋯
6. /api/posts.json /api/posts.json?include=author /api/posts.json?include=author,comments /api/posts.json?cover=true&include=author,comments /api/posts.json?cover=true&include=author,comments_with
7. API 應該是這樣
8. 不是這樣
9. Q: 那這個 app 需要多少 API Endpoints 呢?
10. Ans: 1
11. Ans: 1 GraphQL
12. $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name": "Lucy", "bio":"...", "followers": [◌], "repos": [◌, ◌]
 } $ { "name": "Ja "bio":"..." "followers" "repos": [◌ } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Hello World", "description": "...", "stargazers": [◌, ◌]
 } ! { "name": "Handy Ut "description": ". "stargazers": [◌] } ! { "name": "Awes "description" "stargazers": } ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } ! { } { "viewer": ◌
 } GraphQL
13. $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name": "Lucy", "bio":"...", "followers": [◌], "repos": [◌, ◌]
 } $ { "name": "Ja "bio":"..." "followers" "repos": [◌ } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Hello World", "description": "...", "stargazers": [◌, ◌]
 } ! { "name": "Handy Ut "description": ". "stargazers": [◌] } ! { "name": "Awes "description" "stargazers": } ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } ! { } { "viewer": ◌
 }
14. $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } $ { "name" "bio": "follo "repos } ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Thi "description "stargazers" } ! { } { "viewer": ◌
 } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ d d d d d d d d
15. ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Thi "description "stargazers" } ! ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } { } { "viewer": ◌
 } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name" "bio": "follo "repos } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } $ $ $ $ $ $
16. ! ! { "name": "Thi "description "stargazers" } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } { } { "viewer": ◌
 } $ $ $ $ $ $ $ $ $ $ $ / $ { "name" "bio": "follo "repos } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 }
17. ⬡ GraphQL 簡介 ⬡ Relay ⼿手感評測 ⬡ Relay 基本使⽤用 ⬡ 全端案例例：GraphQL & Relay on Rails
 https:/ /github.com/zetavg/RailsRelayTodoMVC 不會講到跟 Apollo 的比較 Outline
18. ⬡ GraphQL 簡介 ⬡ Relay ⼿手感評測 ⬡ Relay 基本使⽤用 ⬡ 全端案例例：GraphQL & Relay on Rails
 https:/ /github.com/zetavg/RailsRelayTodoMVC 不會講到跟 Apollo 的比較 Outline
19. 基本查詢 ⬢ 最外層⼀一定是 query ⬢ 問什什麼得什什麼 { "data": { "viewer": { "name": "Pokai Chang" } } } query { viewer { name } }
20. 查詢更更多 ⬢ 巢狀狀選取欄欄位 (field) { "data": { "viewer": { "name": "Pokai Chang", "birthday": { "month": 7, "day": 2 } } } } query { viewer { name birthday { month day } } }
21. 巢狀狀查更更多 ⬢ 底下的資料 (node) 可能是同⼀一種類型 (type) { "data": { "viewer": { "name": "Pokai Chang", "following": [ { "name": "..." }, { "name": "..." }, { "name": "..." } ] } } } query { viewer { name following { name } } }
22. 巢狀狀查更更多多多多 ⬢ 可以幹奇怪的事⋯⋯ { "data": { "viewer": { "name": "Pokai Chang", "following": [ { "name": "…", "followers": [ { "name": "Pokai Chang", "following": [ { "name": "…", "followers": [ { "name": "Pokai C query { viewer { name following { name followers { following { name followers { name } } } } } }
23. 型別定義即⽂文件 query { viewer { name birthday { month day } following { name } } } type Query { viewer: User } type User { name: String birthday: Date followers: [User] following: [User] } type Date { year: Integer month: Integer day: Integer }
24. $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name": "Lucy", "bio":"...", "followers": [◌], "repos": [◌, ◌]
 } $ { "name": "Ja "bio":"..." "followers" "repos": [◌ } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Hello World", "description": "...", "stargazers": [◌, ◌]
 } ! { "name": "Handy Ut "description": ". "stargazers": [◌] } ! { "name": "Awes "description" "stargazers": } ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } ! { } { "viewer": ◌
 }
25. $ { "name" "bio": "follo "repos } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Thi "description "stargazers" } ! ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } { } { "viewer": ◌
 } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } query { viewer { name bio } }
26. ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Thi "description "stargazers" } ! ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } { } { "viewer": ◌
 } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name" "bio": "follo "repos } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } query { viewer { name bio followers { name } } }
27. ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } $ { "name" "bio": "follo "repos } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Thi "description "stargazers" } ! { } { "viewer": ◌
 } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } query { viewer { name bio followers { name } repos { name stargazers { name } } } }
28. { } { "viewer": ◌
 } ! ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name" "bio": "follo "repos } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Thi "description "stargazers" } ! query { viewer { name bio followers { name } repos { name stargazers { name } } girlfriend { name } } } '
29. query { viewer { name bio followers { name } repos { name stargazers { name } } girlfriend { name } } } { "errors": [ { "message": "Field 'girlfriend' doesn't
 exist on type ‘User’", ... } ] } '
30. Arguments 參參數 ⬢ 每個 field 會定義可⽤用的參參數 query { user(id: 1) { name } }
31. Arguments 參參數 ⬢ 也可以做巢狀狀查詢 query { user(id: 1) { name repo(name: "awesome-graphql") { name description } } }
32. Fragment 片段 fragment profileFields on User { name bio avatarUrl } query { viewer { ...profileFields } user(id: 1) { ...profileFields } } 先把固定會⽤用到的欄欄位 存成有意義的片段
33. 改資料 ? Mutation ⬢ query 改成 mutation，data 放在 arguments ⬢ 其實就像 HTTP GET/POST，只是慣例例，沒有硬性限制 mutation { addComment(input: { subjectId: 1, body: "Hi." }) { subject { comments { body } } } }
34. graphql.org
35. ⬡ GraphQL 簡介 ⬡ Relay ⼿手感評測 ⬡ Relay 基本使⽤用 ⬡ 全端案例例：GraphQL & Relay on Rails
 https:/ /github.com/zetavg/RailsRelayTodoMVC 不會講到跟 Apollo 的比較 Outline
36. 無限捲軸 Caching Prefetch Caching Server Data Updating Optimistic Update Realtime Update
37. facebook.github.io/relay
38. Relay
 
 Relay Modern (Relay 1.0)
40. const View = (data) => UI
41. Redux 資料流 View State subscribe Redux Store
42. Redux 資料流 View State Reducer Action subscribe prevState
43. Redux 資料流 View State Reducer Action subscribe prevState Backend ?
44. Redux 資料流 ? View State Reducer Action subscribe prevState Backend Action Action Action
45. Redux 資料流 ? View Action Action Action Action Backend State State State Reducer Reducer Reducer Reducer ??? ???
46. $ { "name": "Neson", "bio":"Yet another geek.", "followers": [◌, ◌, ◌], "repos": [◌, ◌, ◌]
 } $ { "name": "Lucy", "bio":"...", "followers": [◌], "repos": [◌, ◌]
 } $ { "name": "Ja "bio":"..." "followers" "repos": [◌ } $ { "name": "Pusheen", "bio":"Nyan nyan nyan~", "followers": [◌], "repos": [◌]
 } ! { "name": "Thing Compiler", "description": "...", "stargazers": [◌, ◌, ◌]
 } ! { "name": "Hello World", "description": "...", "stargazers": [◌, ◌]
 } ! { "name": "Handy Ut "description": ". "stargazers": [◌] } ! { "name": "Awes "description" "stargazers": } ! { "name": "Todo", "description": "...", "stargazers": [◌]
 } ! { } { "viewer": ◌
 } GraphQL
47. Relay 的狀狀況 View $ $ $ $ $ d d $ $ $ $ d d d d d d Relay Store
48. Relay 的狀狀況 View $ $ $ $ d d $ $ $ $ d d d d d d Relay Store viewer { name bio } $ Backend query { viewer { name bio } } { "data": { "viewer": { "name": "…", "Bio": "…" } } }
49. Relay 的狀狀況 View ㄎ ㄎ ㄎ ㄎ $ $ $ $ d d $ $ $ $ d d d d d d Relay Store viewer { name bio } $
50. Relay 的狀狀況 View ㄎ ㄎ ㄎ ㄎ d d d d d d d d $ $ $ $ $ $ $ viewer { name bio } $ $ viewer { followers { name } } Backend query { viewer { followers { name } } } { "data": { "viewer": { "followers": […] } } } Relay Store Request only the diff!
51. Relay 的狀狀況 View ㄎ ㄎ ㄎ ㄎ d d d d d d d d $ $ $ $ $ $ $ viewer { name bio } $ $ viewer { followers { name } }
52. Relay 的狀狀況 viewer { name bio } View $ ㄎ ㄎ ㄎ ㄎ $ $ $ $ $ $ $ $ viewer { followers { name } } d d d d d d d d viewer { repos { name description } } Backend query { viewer { repos { name description } } } { "data": { "viewer": { "repos": […] } } }
53. Relay 的狀狀況 viewer { name bio } View $ ㄎ ㄎ ㄎ ㄎ $ $ $ $ $ $ $ $ viewer { followers { name } } d d d d d d d d viewer { repos { name description } }
54. Relay 的狀狀況 View $ ㄎ ㄎ ㄎ ㄎ $ $ $ $ $ $ $ $ d d d d d d d d RenameRepoMutation( repoID: "…", name: "" )
55. Relay 的狀狀況 View $ ㄎ ㄎ ㄎ ㄎ $ $ $ $ $ $ $ $ d d d d d d d d RenameRepoMutation( repoID: "…", name: "" ) Optimistic Updater
56. Relay 的狀狀況 View $ ㄎ ㄎ ㄎ ㄎ $ $ $ $ $ $ $ $ d d d d d d d d RenameRepoMutation( repoID: "…", name: "" ) Optimistic Updater Backend Updater
57. Relay 的狀狀況 View $ ㄎ ㄎ ㄎ ㄎ $ $ $ $ $ $ $ $ d d d d d d d d RenameRepoMutation( repoID: "…", name: "" ) Optimistic Updater Backend Updater
58. 想分⾴頁 ? Connections ⬢ 游標分⾴頁法：Relay Cursor Connections query { viewer { friends(first: 10, after: "someCursor") { edges { cursor node { id name } } pageInfo { hasNextPage } } } } Edge (UserEdgeType) Node (UserType) { … } Cursor 游標 Connection Edges Edge (UserEdgeType) Node (UserType) { … } Cursor Edge (UserEdgeTy Node (UserType { … } Cursor Page Info 起始游標
59. ⬢ Offset based pagination ⬢ Cursor based pagination Why Cursor? page 1 page 2 page 1 page 2 page 3 page 3 ' 壞ㄌ next 5 next 5
60. ⬡ Relay 可信的 Optimistic Updater 機制可以做 「連線問題時重試」甚⾄至離線更更動上線後同步 ⬡ Relay 的 backend 不⼀一定要是 server，也許可以 是裝置上的 database ⬡ 再狂⼀一點，也許我們還能透過⾃自⼰己實作 Relay RecordSource 組出這樣的架構： Fun Things to Try Relay Relay View Server Client DB Memory
61. Optimistic Update Management
66. { 歡樂 Demo 時間 }
67. 適⽤用情況 ⬢ Data driven，data 越多越雜，投資越划算 ⬢ React app ⬢ 略略懂後端 ⬢ 踩雷的勇氣 Relay Environment Handler Provider Network Layer Store Record Source GraphQL Endpoint Query Renderer Container Component Fragment Query
68. 跟後端不熟？
69. ⬡ GraphQL 簡介 ⬡ Relay ⼿手感評測 ⬡ Relay 基本使⽤用 ⬡ 全端案例例：GraphQL & Relay on Rails
 https:/ /github.com/zetavg/RailsRelayTodoMVC 不會講到跟 Apollo 的比較 Outline
70. 在 React 專案中安裝 Relay $ yarn add react-relay
71. 安裝 GraphQL 語法識別外掛 $ yarn add --dev babel-plugin-relay
72. 記得⼿手動加 Babel Plugin ⬢ 編輯 .eslintrc 或 package.json "plugins": [ "relay", ]
73. 安裝 Relay GraphQL 編譯器 $ yarn add --dev relay-compiler
74. 使⽤用 relay-compiler ⬢ 在 JavaScript 裡寫的 GraphQL 需要被事先編譯⋯⋯
 
 ⬢ 改了了 graphql`…` tag 裡⾯面的內容後都要跑⼀一次 ⬢ 或是加上 --watch 參參數監看變化 $ relay-compiler --src ./src --schema ./schema.graphql 源碼⽬目錄 GraphQL Schema 檔位置
75. import { Environment } from ‘relay-runtime’ const environment = new Environment({ network, store, }) export default environment 環境準備 Relay Environment Handler Provider Network Layer Store Record Source GraphQL Endpoint Network Layer Store ⬢ 先看整個環境⋯⋯
76. import { Network } from ‘relay-runtime' const API_ENDPOINT = 'https://api.github.com/graphql' const fetchQuery = (operation, variables) => { return fetch(API_ENDPOINT, { method: 'POST', body: JSON.stringify({ query: operation.text, variables, }), }).then(response => response.json()) } const network = Network.create(fetchQuery) exports default network Relay 網路路層 ⬢ 給⼀一個溝通介⾯面，⼀一般就是包裝 fetch Relay Environment Handler Provider Network Layer Store Record Source GraphQL Endpoint
77. import { RecordSource, Store, } from 'relay-runtime' const source = new RecordSource() const store = new Store(source) export default store Relay 倉儲 Relay Environment Handler Provider Network Layer Store Record Source GraphQL Endpoint ⬢ Relay 內建具備 garbage collection 的 in-memory record source
78. 以上，前置準備完成
79. const MyProfile = () => ( <QueryRenderer environment={environment} query={graphql` query MyProfileQuery { viewer { name } } `} render={({ error, props }) => { if (error) { return <Text>{error.message}</Text> } else if (props) { return <Text>Hello, {props.viewer.name}!</Text> } return <Text>Loading...</Text> }} /> ) 基本招 QueryRenderer 可以設計載入中假畫⾯面 注意名字有規定⽤用 "[檔案名稱]Query" Relay Environment Handler Provider Network Layer Store Record Source GraphQL Endpoint Query Renderer Component Query
80. const UserProfileComponent = ({ user }) => ( <Text>Hello, {user.name}!</Text> ) const UserProfile = createFragmentContainer( UserProfileComponent, graphql` fragment UserProfile_user on User { name login avatarUrl } `, ) export default UserProfile 拆元件 FragmentContainer 注意名字也有規定⽤用 "[檔案名稱]_[prop 名稱]" Relay Environment Store Query Renderer Container Component Fragment Query
81. 拆元件 FragmentContainer 直接引⽤用定義在 Container 裡的 Fragment Relay Environment Store Query Renderer Container Component Fragment Query import MyProfile from '...' const MyProfile = () => ( <QueryRenderer environment={environment} query={graphql` query MyProfileQuery { viewer { ...UserProfile_user } } `} render={({ error, props }) => { if (error) { return <Text>{error.message}</Text> } else if (props) { return <MyProfile user={props.viewer} /> } return <Text>Loading...</Text> }} /> )
82. Component Tree 層層疊疊 Query Renderer Container Fragment Query Container Container Component Component Fragment Fragment const UserProfileComponent = ({ user }) => ( <View> <UserName user={user} /> <UserBio user={user} /> </View> ) const UserProfile = createFragmentContainer( UserProfileComponent, graphql` fragment UserProfile_user on User { ...UserName_user ...UserBio_user } `, ) const UserNameComponent = ({ user }) => ( <Text>Hello, {user.name}!</Text> ) const UserName = createFragmentContainer( UserNameComponent, graphql` fragment UserName_user on User { name avatarUrl } `, ) const UserBioComponent = ({ user }) => ( <Text>{user.bio}</Text> ) const UserBio = createFragmentContainer( UserBioComponent, graphql` fragment UserBio_user on User { bio } `, )
83. 特種 Container ⬢ RefetchContainer ⬡ 提供 instance method 可以改⽤用不同 arguments 索取資料 ⬢ PaginationContainer ⬡ RefetchContainer 進化版 ⬡ ⽤用 Relay Connection 做分⾴頁專⽤用 ⬡ 可以做出 loadMore()、refresh() 等 method 給無限捲軸和 pull to refresh 使⽤用
84. Mutation const mutation = graphql` mutation AddCommentMutation( $input: AddCommentInput! ) { addComment(input: $input) { clientMutationId commentEdge { cursor node { id body } } subject { id commentsCount } } } ` let variables = { input: { subjectId: "aGVsbG8=", body: "Hello Relay", } } commitMutation( environment, { mutation, variables, onCompleted: (response) => { console.log('Success!') }, onError: (err) => { console.error(err) }, }, ) 1 2 3 1 2 3 ⼀一樣有命名規定 宣告 $input 變數以及型別，內容可以在使⽤用時再指定 與 query ⼀一樣列列出欄欄位，這裡需要列列出所有 mutation 執⾏行行後會變更更或新增的資料 2
85. ⬢ 還有需要做的事⋯⋯ Mutation Updater const mutation = graphql` mutation AddCommentMutation( $input: AddCommentInput! ) { addComment(input: $input) { clientMutationId commentEdge { cursor node { id body } } subject { id commentsCount } } } ` Mutation 執⾏行行後，我們需要把新的 edge 安插到
 某個 subject 底下的 comments connection 若若在 payload root 發現具有 id 的 node，
 Relay 慣例例會幫我們更更新好 store 中相應的 node
86. Mutation Updater commitMutation( environment, { mutation, variables: { ... }, updater: (store) => { const payload = store.getRootField('addComment') const newEdge = payload.getLinkedRecord('commentEdge') const subject = payload.getLinkedRecord('subject') const conn = ConnectionHandler.getConnection(subject, ‘commentsConnection') ConnectionHandler.insertEdgeAfter(conn, newEdge) }, optimisticUpdater: (store) => { … }, }, ) 可⾃自訂 store 的 update ⽅方式
87. Mutation Updater ConnectionHandler.insertEdgeAfter(conn, newEdge) }, optimisticUpdater: (store) => { const subject = store.get(subjectID) const newCommentID = `client:newComment:${tempID++}` const newNode = store.create(newCommentID, 'Comment') newNode.setValue(newCommentID, 'id') newNode.setValue(variables.input.body, 'body') const newEdge = store.create( `client:newCommentEdge:${tempID++}`, 'TodoItemEdge', ) newEdge.setLinkedRecord(newNode, 'node') const conn = ConnectionHandler.getConnection(subject, 'commentsConnection') ConnectionHandler.insertEdgeAfter(conn, newEdge) subject.setValue( subject.getValue('commentsCount') + 1, 'commentsCount', ) }, }, ) 製作出暫時的 node 製作出暫時的 edge 把暫時的 edge 安插進 connection ⼿手動更更新計數器
88. ⬡ GraphQL 簡介 ⬡ Relay ⼿手感評測 ⬡ Relay 基本使⽤用 ⬡ 全端案例例：GraphQL & Relay on Rails
 https:/ /github.com/zetavg/RailsRelayTodoMVC 不會講到跟 Apollo 的比較 Outline
89. (GraphQL + Relay) on Rails
90. (GraphQL + Relay) on Rails 全端⼀一天可以寫完，拿來來做 RN 更更顯神⼒力力
91. (GraphQL + Relay) on Rails Debug 省下的時間可以拿來來調各種 1px
92. Image source: https:/ /blog.codinghorror.com/learn-to-read-the-source-luke/ 請⾒見見 https:/ /github.com/zetavg/RailsRelayTodoMVC
93. Thanks + Q&A