Implement your GraphQL server on Firebase Function

Why

SPA and Mobile App need just one single endpoint to graphql.

This way can not implement subscription with ws backend. I think I don't need it because firestore will resolve it.

What I will not write in this article...

• How to deploy to firebase
• GraphQL Server implementation
• webpack / npm install / package.json

functions code

functions/index.js

const functions = require('firebase-functions')
const express = require('express')
const { graphqlExpress } = require('apollo-server-express')
const bodyParser = require('body-parser')
const { makeExecutableSchema } = require('graphql-tools')

const schema = makeExecutableSchema({
  typeDefs: [/* Your schema.graphql */],
  resolvers: {/* Your resolver */}
})

const server = express().use(
  bodyParser.json(),
  graphqlExpress({ schema, context: {} })
)

exports.graphql = functions.https.onRequest(server)

Send request to graphql

At first you need firebase deploy

Write your firebase.rules to proxy graphql endpoint

{
  "functions": {
    "source": "functions"
  },
  "hosting": {
    "rewrites": [
      {
        "source": "/api/graphql",
        "function": "graphql"
      }
    ]
  }
}

Run firebase serve on your lacal and request query by apollo client.

import 'isomorphic-fetch'
import { ApolloClient } from 'apollo-client'
import { HttpLink } from 'apollo-link-http'
import { InMemoryCache } from 'apollo-cache-inmemory'
import gql from 'graphql-tag'

const client = new ApolloClient({
  link: new HttpLink({ uri: 'http://localhost:5000/api/graphql' }),
  cache: new InMemoryCache()
})

client.query({
  query: gql`<your query>`
}).then(ret => {
 console.log(ret)
})

CAUTION:2017/11/27 I have a problem about apollo-link so I add work arround to node_modules directly. https://github.com/apollographql/apollo-link/issues/248