server.js

const {
  ApolloServer,
  AuthenticationError
} = require("apollo-server")
const mongoose = require('mongoose')
const path = require('path')
const fs = require('fs')
const User = require("./models/User")
const Post = require("./models/Post")
require("dotenv").config({
  path: "variables.env"
})
const jwt = require('jsonwebtoken')

// Import typeDefs.gql & resolver.js
const filePath = path.join(__dirname, "typeDefs.gql")
const typeDefs = fs.readFileSync(filePath, "utf-8")
const resolvers = require('./resolvers')

// Connect to MongoDb Atlas cluster
mongoose.connect(process.env.MONGO_URI, {
    useNewUrlParser: true,
  }).then(() => console.log("MongoDB connected"))
  .catch(err => console.error(err));
mongoose.set('useCreateIndex', true)

// Verify JWT Token passed from client
const getUser = async token => {
  if (token) {
    try {
      return await jwt.verify(token, process.env.SECRET)
    } catch (err) {
      throw new AuthenticationError('Your session has ended. Please sign in again')
    }
  }
}

// Initialize Apollo/GraphQL Server
const server = new ApolloServer({
  typeDefs,
  resolvers,
  // format authentication errors for ui notifications
  formatError: error => ({
    name: error.name,
    message: error.message
  }),
  context: async ({
    req
  }) => {
    const token = req.headers["authorization"]
    return {
      User,
      Post,
      currentUser: await getUser(token)
    }
  },
  playground: {
    endpoint: '/playground',
    settings: {
      'editor.theme': 'light',
      "editor.cursorShape": "block",
    },
  }
});

// Start the HTTP server to listen for connections
server.listen({
  port: process.env.PORT || 4000
}).then(({
  url
}) => {
  console.log(` 🚀  Server live at  ${url}`);
});