启动 Apollo 服务器

如何解决启动 Apollo 服务器

嘿，我开始通过做 Frontend Masters' course Introduction to GraphQL (repo) 来学习 graphQL。 我会从上下文开始，但我到处看，什么也没有，我也试图改变它，但它总是相同的输出。如果有人能提供帮助，我将非常非常感激。

我正在尝试使用下一个代码启动服务器：

    import { ApolloServer } from 'apollo-server'
    import { loadTypeSchema } from './utils/schema'
    import { authenticate } from './utils/auth'
    import { merge } from 'lodash'
    import config from './config'
    import { connect } from './db'
    import product from './types/product/product.resolvers'
    import coupon from './types/coupon/coupon.resolvers'
    import user from './types/user/user.resolvers'
    
    const types = ['product','coupon','user']
    
    export const start = async () => {
      const rootSchema = `
        type Cat {
          name: String
        }
        
        type _Query {
          myCat: Cat
        }
        
        schema {
          query: _Query
          mutation: Mutation
    }
      `
      const schemaTypes = await Promise.all(types.map(loadTypeSchema))
    
      const server = new ApolloServer({
        typeDefs: [rootSchema,...schemaTypes],resolvers: {
          _Query: {
            myCat(){
              console.log('Hello there')
              return {name:'Ivar'}
            }
          },async context({ req }) {
            const user = await authenticate(req)
            return { user }
          }
        }
      }
      )
    
      await connect(config.dbUrl)
      const {url} = await server.listen({port: config.port})
      console.log(`GQL server ready at ${url}`)
    }

数据库文件：

    import mongoose from 'mongoose'
    import options from './config'
    
    export const connect = (url = options.dbUrl,opts = {}) =>
    { return mongoose .connect(url,{
      useNewUrlParser: true,useCreateIndex: true,useUnifiedTopology: true })
        .then(() => console.log('Database Connected'))
        .catch(err => console.log(err))

}

奇怪的是，在某些时候它运行良好，我进行了更改，但并不重要。

控制台输出是这样的：

    ...
    $ node dist/index.js
    (node:17124) UnhandledPromiseRejectionWarning: Error: "context" defined in resolvers,but not in schema (Use `node --trace-warnings ...` to show where the warning was created)
    (node:17124) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block,or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection,use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
    (node:17124) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future,promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
    [nodemon] clean exit - waiting for changes before restart

我确定这是一个愚蠢的错误，但它让我害怕。

解决方法

context 是您传递给 ApolloServer 的配置对象的一部分，而不是其 .resolvers 对象的一部分。

const server = new ApolloServer({
  typeDefs: [rootSchema,...schemaTypes],resolvers: {
    _Query: {
      myCat(){
        console.log('Hello there')
        return {name:'Ivar'}
      }
    },},async context({ req }) {
    const user = await authenticate(req)
    return { user }
  },})