在graphql中合并不同的模式答案

【问题标题】：merge different schema in graphql在graphql中合并不同的模式
【发布时间】：2021-02-05 19:26:17
【问题描述】：

schema.js

const { buildSchema } = require('graphql');

module.exports = buildSchema(`
type Booking {
    _id: ID!
    event: Event!
    user: User!
}

type Event {
    _id: ID!
    title: String!
    description: String!
    price: Float!
    creator: User
}

type User {
    _id: ID!
    email: String!
    password: String
    createdEvents: [Event!]
}
type RootQuery {
    events: [Event!]!
    users: [User!]!
    bookings: [Booking!]!
}

schema {
    query: RootQuery
}

`);

index.js

app.use(
'/graphql',
graphqlHTTP({
    schema: graphQlSchema,
    rootValue: graphQlResolvers,
    graphiql: true
})
);

我只是想学习 graphql，这是我的第一次，所以我有点困惑上面的查询工作正常，但我想要 3 个不同的文件用于预订、用户、事件并将它们合并到一个文件名索引中。 js，然后在主 index.js 中导入，它高于一个。这是我第一次学习graphql。任何帮助将不胜感激

【问题讨论】：

标签： node.js graphql apollo-server express-graphql

【解决方案1】：

您可以使用graphql-tools 包中的Type definitions (SDL) merging 来合并您的类型定义文件。

此工具合并了 GraphQL 类型定义和架构。它旨在合并所有可能的类型、接口、枚举和联合，而不会发生冲突。

例如

types/booking.js:

module.exports = `
type Booking {
    _id: ID!
    event: Event!
    user: User!
}
`;

types/user.js:

module.exports = `
type User {
    _id: ID!
    email: String!
    password: String
    createdEvents: [Event!]
}
`;

types/event.js:

module.exports = `
type Event {
    _id: ID!
    title: String!
    description: String!
    price: Float!
    creator: User
}
`;

types/index.js:

const { mergeTypeDefs } = require('@graphql-tools/merge');
const bookingType = require('./booking');
const userType = require('./user');
const eventType = require('./event');

const rootTypes = `
type RootQuery {
    events: [Event!]!
    users: [User!]!
    bookings: [Booking!]!
}

schema {
    query: RootQuery
}
`;

const types = [bookingType, userType, eventType, rootTypes];

module.exports = mergeTypeDefs(types);

server.js:

const express = require('express');
const { graphqlHTTP } = require('express-graphql');
const { buildSchema, print } = require('graphql');
const typeDefs = require('./types');

const app = express();
const port = 4000;
const schema = buildSchema(print(typeDefs));
console.log(print(typeDefs));

app.use(
  '/graphql',
  graphqlHTTP({
    schema,
    graphiql: true,
  }),
);

app.listen(port, () => console.log('Server started at port:', port));

服务器日志：

type Booking {
  _id: ID!
  event: Event!
  user: User!
}

type User {
  _id: ID!
  email: String!
  password: String
  createdEvents: [Event!]
}

type Event {
  _id: ID!
  title: String!
  description: String!
  price: Float!
  creator: User
}

type RootQuery {
  events: [Event!]!
  users: [User!]!
  bookings: [Booking!]!
}

schema {
  query: RootQuery
}

Server started at port: 4000

【讨论】：