server.js

require("dotenv").config();
const express = require("express");
const path = require("path");
const PORT = process.env.PORT || 3001;
const app = express();
const passport = require("passport");
const mongoose = require("mongoose");
const userController = require('./controllers/userController');

//connect to MongodDB
const MONGODB_URI = process.env.MONGODB_URI
  || "mongodb://localhost/sitedb";
mongoose.connect(MONGODB_URI, { useNewUrlParser: true });

let session = require("express-session")({
  secret: process.env.SESSION_SECRET,
  resave: false,
  saveUninitialized: false
});

const GitHubStrategy = require("passport-github2").Strategy;

let strategy = new GitHubStrategy(
  {
    clientID: process.env.NODE_ENV === "production" ? process.env.GITHUB_CLIENT_ID_PRODUCTION : process.env.GITHUB_CLIENT_ID,
    clientSecret: process.env.NODE_ENV === "production" ? process.env.GITHUB_CLIENT_SECRET_PRODUCTION : process.env.GITHUB_CLIENT_SECRET,
    callbackURL: process.env.NODE_ENV === "production" ? null : "/auth/github/callback"
  },
  (accessToken, refreshToken, profile, done) => done(null, profile)
);

//use Github OAuth2 strategy
passport.use(strategy);

passport.serializeUser((user, done) => done(null, user));

passport.deserializeUser((profile, done) => {
  if (!profile) done(null, {});
  user = {
    username: profile.username,
    avatar_url: profile._json.avatar_url, //profile.photos[0].value, 
    display_name: profile.displayName,
    email: (profile.emails ? profile.emails[0].value : null)
  }
  userController.createOrUpdate(user)
    .then(dbUser => done(null, dbUser))
    .catch(err => done(err, null));
});

// Define middleware here
app.use(express.urlencoded({ extended: true }));
app.use(express.json());

// Serve up static assets (usually on heroku)
if (process.env.NODE_ENV === "production") {
  app.use(express.static("client/build"));
}
app.use(require("cookie-parser")());

app.use(session);
app.use(passport.initialize());
app.use(passport.session());

// Define API routes here

app.use("/auth", require("./routes/authRoutes")(passport));
app.use("/api", require("./routes/apiRoutes"));
app.use("/util", require("./routes/utilRoutes"));

// Send every other request to the React app
// Define any API routes before this runs
app.get("*", (req, res) => {
  res.sendFile(path.join(__dirname, "./client/build/index.html"));
});

app.listen(PORT);