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apollo express nuxt.js websocket subscription

Apollo Server as Nuxt serverMiddleware

发布于 2020-03-28 23:14:19

I've managed to have a express + Apollo Backend as a serverMiddleware in Nuxtjs. Everything works fine(auth, cache, datasources, queries, mutations) but now I'm trying to get subscriptions(websockets) running and its giving me a hard time.

I tried this example https://www.apollographql.com/docs/apollo-server/data/subscriptions/#subscriptions-with-additional-middleware but even letting the httpServer listening didn't work.

This is my API file which I require through the nuxt.config.js with '~/api/index' :

module.exports = async () => {
  const app = require('express')()
  const server = await require("./apollo")() // apollo-server-express w/ typeDefs and resolvers

  // apply Apollo to Express
  server.applyMiddleware({ app });
  console.log(`???? ApolloServer ready at ${server.graphqlPath}`);

  const httpServer = http.createServer(app);
  server.installSubscriptionHandlers(httpServer);
  console.log(`???? ApolloSubscriptions ready at ${server.subscriptionsPath}`);

  return {
    path: '/api',
    handler: httpServer
  }
}

Now my playground is giving me this error: "Could not connect to websocket endpoint ws://192.168.150.98:3000/api/graphql. Please check if the endpoint url is correct."

TypeDefs:

type Subscription {
  postAdded: Post
}
type Post {
  author: String
  comment: String
}
type Query {
  posts: [Post]
}
type Mutation {
  addPost(author: String, comment: String): Post
}

Resolvers:

Query: {
  posts(root, args, context) {
    return Posts;
  }
}
Mutation: {
  addPost(root, args, context) {
    pubsub.publish(POST_ADDED, { postAdded: args });
    return Posts.add(args);
  }
},
Subscription: {
  postAdded: {
    // Additional event labels can be passed to asyncIterator creation
    subscribe: () => pubsub.asyncIterator([POST_ADDED]),
  },
}

First question here, thank u in advance! :)

Questioner
jliehmann
Viewed
141
jliehmann 2020-01-31 17:36

I found a hacky way to achieve it, import the code as a nuxt module:

import http from 'http'

export default function () {
  this.nuxt.hook('render:before', async () => {
    const server = require("./apollo")()

    // apply Apollo to Express
    server.applyMiddleware({ app: this.nuxt.renderer.app });
    console.log(`???? ApolloServer ready at ${server.graphqlPath}`);

    const httpServer = http.createServer(this.nuxt.renderer.app);

    // apply SubscriptionHandlers to httpServer
    server.installSubscriptionHandlers(httpServer);
    console.log(`???? ApolloSubscriptions ready at ${server.subscriptionsPath}`);

    // overwrite nuxt.server.listen()
    this.nuxt.server.listen = (port, host) => new Promise(resolve => httpServer.listen(port || 3000, host || 'localhost', resolve))

    // close this httpServer on 'close' event
    this.nuxt.hook('close', () => new Promise(httpServer.close))
  })
}

Tho I'm now using a probably more stable way, using nuxt programmatically! With hapi instead of express, since express is giving me trouble compiling and not showing the loading-screen(progress of building). Just use npx create-nuxt-app and create an app with a hapi server backend.

The code with hapi would look like this:

const consola = require('consola')
const Hapi = require('@hapi/hapi')
const HapiNuxt = require('@nuxtjs/hapi')

async function start () {
  const server = require('./apollo/index')()
  const app = new Hapi.Server({
    host: process.env.HOST || '127.0.0.1',
    port: process.env.PORT || 3000
  })

  await app.register({
    plugin: HapiNuxt
  })

  app.route(await require('./routes')())

  await server.applyMiddleware({
    app,
    path: '/graphql'
  });
  console.log(`???? ApolloServer ready at ${server.graphqlPath}`);
  await server.installSubscriptionHandlers(app.listener)
  console.log(`???? ApolloSubscriptions ready at ${server.subscriptionsPath}`);

  await app.start()

  consola.ready({
    message: `Server running at: ${app.info.uri}`,
    badge: true
  })
}
process.on('unhandledRejection', error => consola.error(error))
start().catch(error => console.log(error))

Maybe i can help somebody