Sample project structure to multiple files

 

#.gitignore
###########
node_modules
keys.js

#package.json
############
{
  "name": "server",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "engines": {
    "node": "12.16.3",
    "npm": "6.14.4"
  },
  "scripts": {
    "start": "node index.js",
    "dev": "nodemon index.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "express": "^4.17.1",
    "nodemon": "^2.0.4",
    "passport": "^0.4.1",
    "passport-google-oauth20": "^2.0.0"
  }
}

index.js

const express = require('express');
require('./services/passport');

const app = express();

require('./routes/authRoutes')(app);

const PORT = process.env.PORT || 5000;
app.listen(PORT);

services\passport.js

const passport = require('passport');
const GoogleStrategy = require('passport-google-oauth20').Strategy;
const keys = require('../config/keys');

passport.use(
  new GoogleStrategy(
    {
      clientID: keys.googleClientID,
      clientSecret: keys.googleClientSecret,
      callbackURL: '/auth/google/callback'
    },
    (accessToken, refreshToken, profile, done) => {
      console.log('access token', accessToken);
      console.log('refresh token', refreshToken);
      console.log('profile', profile);
    }
  )
);

config\keys.js

module.exports = {
  googleClientID: '',
  googleClientSecret: '',
};

routes\authRoutes.js

const passport = require('passport');

module.exports = app => {
  app.get(
    '/auth/google',
    passport.authenticate('google', {
      scope: ['profile', 'email']
    })
  );

  app.get('/auth/google/callback', passport.authenticate('google'));
};