server.js

const { ApolloServer } = require('apollo-server');
const typeDefs = require('./typeDefs');
const resolvers = require('./resolvers');
const { findOrCreateUser } = require('./controllers/userController')
const mongoose = require('mongoose');
require('dotenv').config();

mongoose
    .connect(process.env.MONGO_URI, { useNewUrlParser: true })
    .then(() => console.log('DB Connected'))
    .catch(err => console.error(err));    

const server = new ApolloServer({
    typeDefs,
    resolvers,
    context: async ({ req }) => {
        let authToken = null;
        let currentUser = null;
        try {
            authToken = req.headers.authorization
            if(authToken) {
                currentUser = await findOrCreateUser(authToken);
            }
        } catch(err) {
            console.error(`Unable to authenticate user with token ${authToken}`)
        }
        return { currentUser }
    }
});

server.listen({ 
    port: process.env.PORT || 4000,
}).then(({ url }) => {
    console.log(`Server listening on ${url}`)
});