GraphQL入门3(Mutation)

创建一个新的支持Mutation的Schema.

var GraphQLSchema = require('graphql').GraphQLSchema; var GraphQLObjectType = require('graphql').GraphQLObjectType; var GraphQLString = require('graphql').GraphQLString; var GraphQLList = require('graphql').GraphQLList; var buildSchema  = require('graphql').buildSchema; var fetch = require('node-fetch'); require("babel-polyfill");   // Construct a schema, using GraphQL schema language var schema = buildSchema(                   '    input MessageInput {'                 + '        content: String'                 + '        author: String'                 + '    }'                 + ''                 + '    type Message {'                 + '        id: ID !'                 + '        content: String'                 + '        author: String'                 + '    }'                 + ''                 + '    type Query {'                 + '        getMessage(id: ID!): Message'                 + '    }'                 + ''                 + '    type Mutation {'                 + '         createMessage(input: MessageInput): Message'                 + '         updateMessage(id: ID!, input: MessageInput): Message'                 + '    }'             );       // If Message had any complex fields, we'd put them on this object.     class Message {         constructor(id, {content, author}) {             this.id = id;             this.content = content;             this.author = author;         }     }   // Maps username to content var fakeDatabase = {};   var root = {     getMessage: function ( { id }) {         if (!fakeDatabase[id]) {             throw new Error('no message exists with id ' + id);         }         return new Message(id, fakeDatabase[id]);     },       createMessage: function ({input}) {         // Create a random id for our "database".         var id = require('crypto').randomBytes(10).toString('hex');             fakeDatabase[id] = input;         return new Message(id, input);     },       updateMessage: function ({id, input}) {         if (!fakeDatabase[id]) {             throw new Error('no message exists with id ' + id);         }         // This replaces all old data, but some apps might want partial update.         fakeDatabase[id] = input;         return new Message(id, input);      } };     module.exports.Schema = schema; module.exports.Root = root;

 

创建一个新的router来使用这个Schema:

var express = require('express'); var graphQLHTTP = require('express-graphql'); var schema = require('../schemas/Schema2').Schema; var root = require('../schemas/Schema2').Root; var router = express.Router();   router.use(graphQLHTTP({     schema: schema,     rootValue: root,     graphiql : true }));   module.exports = router;

 

客户端的测试代码如下:

app.js:

//Mutation var Test7 = require('./Test7'); Test7.Execute();

 

Test7.js

//Test7: Mutation    var gRequest = require('graphql-request').request; var util = require('util');   exports.Execute = function () {       var query = 'mutation CreateMessage($input: MessageInput) {'             + '  createMessage(input: $input) {'             + '    id,'             + '    author,'             + '    content'             + '  }'             + '}' ;             var varibles1 =         {             "input":             {                 "author": "Tom",                 "content": "this is my message"             }         };                 //gRequest('http://localhost:1337/graphql/graphql', query).then(function (data) { console.log(data) });     gRequest('http://localhost:1337/graphql2/graphql', query, varibles1).then(function (data) {         console.log(util.inspect(data, { showHidden: false, depth: null }))     });   };

 

执行结果如下:

{ createMessage:    { id: '48ed1228a3b390909365',      author: 'Tom',      content: 'this is my message' } }

 

示例来自: https://graphql.org/graphql-js/mutations-and-input-types/