firebase.js

const functions = require('firebase-functions');
const firebase = require('firebase');
const admin = require('firebase-admin');
const express = require('express');
const path = require('path');

const firebaseApp = firebase.initializeApp(
	functions.config().firebase
);

const index = require('./routes/index');

const app = express();

app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', index);

app.get('/auth/facebook', function(req, res) {
  const provider = new firebase.auth.FacebookAuthProvider();
  firebase.auth().signInWithPopup(provider)
    .catch(err => console.log(err));
});


firebase.auth().onAuthStateChanged(function(user) {
  if (user) console.log('user:', user);
});


// catch 404 and forward to error handler
app.use(function(req, res, next) {
	var err = new Error('Not Found');
	err.status = 404;
	next(err);
});

// error handler
app.use(function(err, req, res, next) {
	// set locals, only providing error in development
	res.locals.message = err.message;
	res.locals.error = req.app.get('env') === 'development' ? err : {};

	// render the error page
	res.status(err.status || 500);
	res.render('error');
});

exports.app = functions.https.onRequest(app);