Configuration

passport.js

'use strict'

const passport = require('passport')
const configuration = require('../config')
const tokens = configuration.tokens

// User models
const UserDB = require('../api/v1/database/user')

// Passport strategies modules
const GoogleStrategy = require('passport-google-oauth2').Strategy

// Passport session setup.

//   To support persistent login sessions, Passport needs to be able to
//   serialize users into and deserialize users out of the session.  Typically,
//   this will be as simple as storing the user ID when serializing, and finding
//   the user by ID when deserializing.  However, since this example does not
//   have a database of user records, the complete Google profile is
//   serialized and deserialized.

passport.serializeUser(function (user, done) {
  done(null, user)
})

passport.deserializeUser(function (obj, done) {
  done(null, obj)
})

// Use the GoogleStrategy within Passport.
//   Strategies in Passport require a `verify` function, which accept
//   credentials (in this case, an accessToken, refreshToken, and Google
//   profile), and invoke a callback with a user object.

// --- GOOGLE STRATEGY -------------------------
// ---------------------------------------------

const GoogleOptions = {
  clientID: String(tokens.google.CLIENT_ID),
  clientSecret: String(tokens.google.CLIENT_SECRET),
  callbackURL: String(tokens.google.CALLBACK_URL),
  passReqToCallback: true
}

const GoogleCallback = function (request, accessToken, refreshToken, profile, done) {
  // asynchronous verification, for effect...
  process.nextTick(function () {
    // To keep the example simple, the user's Google profile is returned to
    // represent the logged-in user.  In a typical application, you would want
    // to associate the Google account with a user record in your database,
    // and return that user instead.

    // http://stackoverflow.com/questions/13272824/combine-two-or-queries-with-and-in-mongoose
    const query = {
      $or: [
        { 'email': email },
        { 'services.google.googleID': googleID }
      ]
    }

    UserDB.getUser(query, (err, user) => {
      if (err) return done(err)

      let newUser = {}

      newUser.username = googleID
      newUser.email = email
      newUser.name = {}
      newUser.name.first = name.first
      newUser.name.last = name.last
      newUser.services = {}
      newUser.services.google = {}
      newUser.services.google.id = googleID
      newUser.services.google.token = accessToken
      newUser.services.google.image = image

      if (user) {
        // We have found the user
        // The user was already on our database.
        // Update the data
        const query = {
          'username': user.username
        }

        UserDB.updateUser(newUser, query, (err, user) => {
          if (err) return done(err)
          return done(null, newUser)
        })
      } else {
        // User not found in our database.
        // Creating a new user in our database for first time
        UserDB.createUser(newUser, (err, user) => {
          if (err) return done(err)
          return done(null, newUser)
        })
      }
    })
  })
}

try {
  passport.use(new GoogleStrategy(GoogleOptions, GoogleCallback))
} catch (e) {
  console.log('----> Problems creating a google strategy')
  console.log('----> Possible: clientID not defined')
}