GraphQL 渐进学习 09-graphql-apollo-client-vue-客户端开发

软件环境

• vue > 2.5.x

目标

• 创建 graphql 客户端
• 封装请求处理
• 基于 token 验证

代码

• ducafecat/eggjs-graphql-example/vue-client

步骤

1 安装依赖包

• npm install

npm install --save vue-apollo graphql apollo-client apollo-link apollo-link-http apollo-cache-inmemory graphql-tag

• webpack.json 包清单

"dependencies": {
    "apollo-cache-inmemory": "^1.2.0",
    "apollo-client": "^2.3.0",
    "apollo-link": "^1.2.2",
    "apollo-link-http": "^1.5.4",
    "element-ui": "^2.3.7",
    "graphql": "^0.13.2",
    "graphql-tag": "^2.9.2",
    "vue": "^2.5.2",
    "vue-apollo": "^3.0.0-beta.5",
    "vue-router": "^3.0.1"
  },

2 编写 webpack 配置

• 文件 build/webpack.base.conf.js

module: {
    rules: [
      ...
      {
        test: /\.(graphql|gql)$/,
        exclude: /node_modules/,
        loader: 'graphql-tag/loader'
      }
      ...
    ]
  }

• 当 import 时，自动做 schema js 包装
• 如 import QUERY_USER from '@/graphql/user.graphql' ，把 QUERY_USER 打印看看

3 编写 config.json 配置

• 文件 src/utils/config.json

{
  "graphqlServer": "http://127.0.0.1:7001/graphql",
  "tokenName": "UU_AUTH_TOKEN"
}

• graphqlServer 服务器地址
• tokenName 本地写 localStorage key 名称 ，推荐大家做本地化可以用 cookie 设置过期时间

4 编写 VueApollo 适配器

• 文件 src/apolloProvider.js

import Vue from 'vue'
import {ApolloClient} from 'apollo-client'
import {HttpLink} from 'apollo-link-http'
import {InMemoryCache} from 'apollo-cache-inmemory'
import VueApollo from 'vue-apollo'
import { ApolloLink, concat, split } from 'apollo-link';
import { getMainDefinition } from 'apollo-utilities';
import Config from '@/utils/config.json'

Vue.use(VueApollo)

const httpLink = new HttpLink({
  uri: Config.graphqlServer,
})

const authMiddleware = new ApolloLink((operation, forward) => {
  const token = localStorage.getItem(Config.tokenName) || null
  operation.setContext({
    headers: {
      Authorization: `Bearer ${token}`
    }
  });
  return forward(operation);
})

const apolloClient = new ApolloClient({
  link: concat(authMiddleware, httpLink),
  cache: new InMemoryCache(),
  connectToDevTools: true,
})

const apolloProvider = new VueApollo({
  defaultClient: apolloClient,
  defaultOptions: {
    $loadingKey: 'loading'
  },
  errorHandler (error) {
    console.log('Global apollo error handler')
    console.error(error)
  }
})

export default apolloProvider

• 文件 src/main.js

import apolloProvider from './apolloProvider'
...
new Vue({
  el: '#app',
  provide: apolloProvider.provide(),
  ...
})

5 编写 schema 定义

• 项目中的请求定义 我都放在了 目录 src/graphql 下，有点像 restful 的 api 定义

.
├── removeUser.graphql
├── user.graphql
└── users.graphql

• 我这里写了 2 个查询 1 个更新操作，名称和服务端定义一致，这样方便查询修改

6 编写 Graphql 请求

• 文件 src/components/HelloWorld.vue
• 官方 readme.md 中只写了一种 组件 方式调用，我还是喜欢 api 方式
• 代码 HelloWorld.vue

6.1 组件 方式

apollo: {
    login: {
      query: gql`
        query queryFun($username: String!, $password: String!) {
          user(username: $username, password: $password) {
            id
            name
            token
          }
        }
      `,
      variables() {
        return {
          username: 'ducafecat',
          password: '345457yftgyhdsfghre'
        }
      },
      manual: true,
      result({data, loading}) {
        console.log(data, loading)
        if (!loading) {
          this.res = data
        }
      }
    }
  }
}
</script>

这种方式做查询，适合功能单一的展示组件，灵活性感觉还是差了点，有兴趣的可以去掉注释大家体会下。

6.2 api 方式

• query 查询

import QUERY_USER from '@/graphql/user.graphql'
...
  methods: {
    handleLogin() {
      this.clearData()
      this.$apollo
        .query({
          // Query
          query: QUERY_USER,
          variables: {
            username: 'ducafecat',
            password: '12321321321321432'
          },
        })
        .then(response => {
          this.loading = false
          this.res = response.data
          localStorage.setItem(Config.tokenName, this.res.user.token)
          alert('登录成功，写入Token完成，重新装载 apolloProvider')
          window.location.reload()
        })
        .catch(error => {
          this.loading = false
          this.err = error
        })
    },

• mutate 更新

handleRemoveUser() {
      this.clearData()
      this.$apollo
        .mutate({
          // Query
          mutation: MUTATION_REMOVE_USER,
          variables: {
            id: 123
          }
        })
        .then(response => {
          this.loading = false
          this.res = response.data
        })
        .catch(error => {
          this.loading = false
          this.err = error
        })
    },

参考

1 文章

• vue-apollo
• Egg/GraphQL
• facebook/GraphQL
• GraphQL API v4
• github/authenticating-with-graphql
• VueConf 2017 demo

2 组件

• vue-apollo
• apollo-client
• jsonwebtoken
• ApolloLink Set headers
• element-ui