index.js

const express = require("express");
const session = require("express-session");
const passport = require("passport");
const dotenv = require("dotenv");
require("./auth");
const path = require("path");
const app = express();
app.use(express.static("public"));
// Config dotenv
dotenv.config();

function isLoggedIn(req, res, next) {
  req.user ? next() : res.sendStatus(401);
}

app.use(session({ secret: "cats", resave: false, saveUninitialized: true }));
app.use(passport.initialize());
app.use(passport.session());

app.get("/", (req, res) => {
  res.send("index.html");
});

app.get(
  "/auth/google",
  passport.authenticate("google", { scope: ["email", "profile"] })
);

app.get(
  "/auth/google/callback",
  passport.authenticate("google", {
    successRedirect: "/protected",
    failureRedirect: "/auth/google/failure",
  })
);

app.get("/protected", isLoggedIn, (req, res) => {
  res.send(`Hello ${req.user.displayName}`);
});

app.get("/logout", (req, res) => {
  req.logout(() => {
    req.session.destroy();
  });
  res.redirect("/");
});

app.get("/auth/google/failure", (req, res) => {
  res.send("Failed to authenticate..");
});

app.listen(5000, () => console.log("listening on port: 5000"));