Express GitHub Auth

github.auth.js

import express from 'express';
import request from 'request';

export default ({
    config: {
        GITHUB_CLIENT_ID,
        GITHUB_CLIENT_SECRET,
        GITHUB_REDIRECT_URI
    },
    models: { User }
}) => {
    const router = express.Router();

    router.use((req, res, next) => {
        if (!req.session.userId) return next();

        User.findById(req.session.userId).then(user => {
            req.user = user;
            res.locals.user = user;

            next();
        });
    });

    router.get('/login', (req, res) => {
        res.redirect(`https://github.com/login/oauth/authorize?client_id=${GITHUB_CLIENT_ID}&redirect_uri=${GITHUB_REDIRECT_URI}&scope=read:user%20user:email`);
    });

    router.get('/login/github', (req, res) => {
        const code = req.query.code;
        
        request({
            method: 'post',
            uri: 'https://github.com/login/oauth/access_token',
            qs: {
                client_id: GITHUB_CLIENT_ID,
                client_secret: GITHUB_CLIENT_SECRET,
                redirect_uri: GITHUB_REDIRECT_URI,
                code
            },
            headers: {
                'Accept': 'application/json'
            }
        }, (error, response, body) => {
            const data = JSON.parse(body);

            request({
                method: 'get',
                uri: 'https://api.github.com/user',
                headers: {
                    'User-Agent': 'olegpolyakov',
                    'Authorization': `token ${data.access_token}`
                }
            }, (error, response, body) => {
                const data = JSON.parse(body);
                
                User.findOne({ githubId: data.id })
                    .then(user => {
                        return user || User.create({
                            username: data.login,
                            name: data.name,
                            email: data.email,
                            githubId: data.id,
                            avatarUrl: data.avatar_url,
                            bio: data.bio
                        });
                    })
                    .then(user => {
                        req.session.userId = user.id;
                        res.redirect('/');
                    })
                    .catch(error => {
                        console.log(error)
                        res.redirect('/');
                    });
            });
        });
    });

    router.get('/logout', (req, res) => {
        req.session.userId = undefined;

        res.redirect('/');
    });

    return router;
};