monzo.js

'use strict';

const http = require('http');
const express = require('express');
const passport = require('passport');
const request = require('request');
const OAuth2Strategy = require('passport-oauth2');
const session = require('express-session');

let r = request.defaults({baseUrl: 'https://api.monzo.com/', json: true});

passport.use(new OAuth2Strategy({
    authorizationURL: 'https://auth.getmondo.co.uk',
    tokenURL: 'https://api.monzo.com/oauth2/token',
    clientID: process.env.CLIENT_ID,
    clientSecret: process.env.CLIENT_SECRET,
    callbackURL: `${process.env.ROOT_URL}/callback`,
    state: true
}, (accessToken, refreshToken, profile, done) => done(null, Object.assign({accessToken, refreshToken}, profile))));
passport.serializeUser((user, done) => done(null, user));
passport.deserializeUser((user, done) => done(null, user));

const app = express();
app.set('view engine', 'pug');
app.use(session({
    secret: process.env.SESSION_SECRET,
    resave: false,
    saveUninitialized: false
}));
app.use(passport.initialize());
app.use(passport.session());
app.get('/login', passport.authenticate('oauth2'));
app.get('/callback', passport.authenticate('oauth2', {successRedirect: '/', failureRedirect: '/login'}));
app.get('/logout', (req, res) => {
    req.logout();
    res.redirect('/');
});

app.get('/', (req, res) => {
    if (!req.isAuthenticated()) {
        return res.render('index');
    }
    r = r.defaults({auth: {bearer: req.user.accessToken}});
    r('/ping/whoami', (error, response, body) => {
        if (response && http.STATUS_CODES[response.statusCode] === 'Unauthorized') {
            req.logout();
            return res.redirect('/');
        }
        const {user_id} = body;
        r('/accounts', (error, response, body) => {
            const {accounts: [account]} = body;
            r('/transactions', {qs: {account_id: account.id}}, (error, response, body) => {
                const {transactions} = body;
                res.render('index', {user_id, account, transactions});
            });
        });
    });
});

app.listen(process.env.PORT);