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/