如何使用 GraphQL 构建 BFF

使用工程接口演示：

var express = require('express');
var graphqlHTTP = require('express-graphql');
var axios = require('axios');
var {
    GraphQLList,
    GraphQLObjectType,
    GraphQLSchema,
    GraphQLString,
    GraphQLInt,
    GraphQLFloat,
    GraphQLEnumType,
    GraphQLNonNull,
    GraphQLInterfaceType,
    GraphQLInputObjectType,
    GraphQLBoolean
} = require('graphql');

const Platform = new GraphQLEnumType({
    name:'Platform',
    description:"平台",
    values: {
        SERVERLESS: {value: 'SERVERLESS'},
        DEEPEXI: {value: 'DEEPEXI.COM'},
    }
});

const Response = new GraphQLObjectType({
    name:'Response',
    description:"响应体",
    fields: () => {
        return ({
            message: {type: GraphQLString},
            success: {type: GraphQLBoolean},
            code: {type: GraphQLString},
            payload: {type: GraphQLString},
        });
    },
});

const Project = new GraphQLObjectType({
    name:'Project',
    description:"工程实体",
    fields: () => {
        return ({
            message: {type: GraphQLString},
            name: {type: new GraphQLNonNull(GraphQLString)},
            tags: {type: new GraphQLNonNull(GraphQLString)},
            description: {type: new GraphQLNonNull(GraphQLString)},
            platform: {
                type: new GraphQLNonNull(GraphQLString),
                args: {
                    platform: {type: Platform}
                }
            },
        });
    },
});

const ProjectInput = new GraphQLInputObjectType({
    name:'ProjectInput',
    description:"工程Input实体",
    fields:()=>({
        name:{type:new GraphQLNonNull(GraphQLString)},
        tags:{type:new GraphQLNonNull(GraphQLString)},
        description:{type:new GraphQLNonNull(GraphQLString)},
        platform:{type:Platform},
    }),
});

const Query = new GraphQLObjectType({
    name:'ProjectQuery',
    description:'工程查询',
    fields:()=>({
        project:{
            type:Project,
            description
            :'根据id查询单个工程',
            args: {
                id: {type: new GraphQLNonNull(GraphQLString)}
            },
            resolve:function (source,{id}) {
                return axios.get(`http://10.50.48.2:39321/v2/projects/${id}?asMember=true`, {
                  headers: {'X-AUTH-USER': '1840', 'X-AUTH-TENANT': 'a0b6f6139e6046129547b3fd27779fb0'}
                }).then(res => {
                  console.log(res)
                  return res.data.payload;
                });
            }
        },
        projects:{
            type:new GraphQLList(Project),
            description:'查询全部工程列表',
            resolve:function () {
              return axios.get(`http://10.50.48.2:39321/v2/projects/page?index=1&size=20&own=false`, {
                headers: {'X-AUTH-USER': '1840', 'X-AUTH-TENANT': 'a0b6f6139e6046129547b3fd27779fb0'}
              }).then(res => {
                console.log(res)
                return res.data.payload.rows;
              });
            }
        }
    }),
});

const Mutation = new GraphQLObjectType({
    name:'ProjectMutation',
    description:'工程操作',
    fields:()=>({
        add:{
            type:Response,
            description:'添加工程',
            args: {
              name: {type: new GraphQLNonNull(GraphQLString)},
              tags: {type: new GraphQLNonNull(GraphQLString)},
              description: {type: new GraphQLNonNull(GraphQLString)},
              platform: {
                  type: new GraphQLNonNull(GraphQLString),
                  args: {
                      platform: {type: Platform}
                  }
              }
            },
            resolve:function (source,{name,tags,description,platform}) {
                var project={
                    name:name,
                    tags:tags,
                    description:description,
                    platform:platform
                };
                console.log(project)
                return axios.post(`http://10.50.48.2:39321/v2/projects`, project, {
                  headers: {'X-AUTH-USER': '1840', 'X-AUTH-TENANT': 'a0b6f6139e6046129547b3fd27779fb0'}
                }).then(res => {
                  console.log(res.data)
                  return res.data;
                }).catch(res => {
                  console.log(res.response.data)
                  return res.response.data;
                });
            }
        },
        addByInput:{
            type:Project,
            description:'通过Input添加工程',
            args: {
                projectInfo:{type: ProjectInput},
            },
            resolve:function (source,{projectInfo}) {
                console.log(projectInfo);
                var project={
                  name:projectInfo.name,
                  tags:projectInfo.tags,
                  description:projectInfo.description,
                  platform:projectInfo.platform
                };
                return axios.post(`http://10.50.48.2:39321/v2/projects`, project, {
                  headers: {'X-AUTH-USER': '1840', 'X-AUTH-TENANT': 'a0b6f6139e6046129547b3fd27779fb0'}
                }).then(res => {
                  console.log(res.data)
                  return res.data;
                }).catch(res => {
                  console.log(res.response.data)
                  return res.response.data;
                });
            }
        }
    }),
});

const schema = new GraphQLSchema({
    query: Query,
    mutation: Mutation
});

var app = express();
app.use('/graphql', graphqlHTTP({
    schema: schema,
    graphiql: true, //启用GraphiQL
}));

app.listen(4000, () => console.log('请在浏览器中打开地址：localhost:4000/graphql'));

package.json

{
  "name": "GraphQL-Deepexi",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "lxh",
  "license": "ISC",
  "devDependencies": {
    "express": "^4.15.3",
    "express-graphql": "^0.6.5",
    "graphql": "^0.9.6"
  },
  "dependencies": {
    "axios": "^0.20.0"
  }
}

• 执行命令

npm install
node ${filename}.js

• 创建工程

  
  
  

  image.png

• 根据id获取单个工程
  

  image.png

• 获取工程列表
  

  image.png