Stateless login-with microservice for OAuth

About

Stateless authentication microservice for “login-with” functionality, supporting:

• Twitter
• GitHub
• Reddit
• Facebook
• Google
• LinkedIn
• Instagram
• Mixer
• Spotify
• Strava
• … more to come (PRs welcome)

You can deploy with now or Docker (for mandatory and optional env variables see below).

$ now lipp/login-with
$ docker run lipp/login-with

This microservice must run in a subdomain of yours, e.g. login.yourdomain.com.

<a href='https://login.yourdomain.com/twitter?success=ON_SUCCESS_URL&failure=ON_FAILURE_URL'>
  Login with Twitter
</a>

On successful login two cookies will be created:

• jwt - A “JSON Web Token” (JWT) containing profile information and the respective access tokens (Twitter/etc). http-only!
• profile - A JSON string which containing non-sensitive information (accessible from browser JS):
  • username - string / mandatory, the account specific user alias (e.g. Twitter name)
  • photo - string / optional, the account specific user image link
  • name - string / optional, the “real” name

The cookies will be available for your toplevel domain and all subdomains. In addition, the cookie’s secure flag is set, which means that your other websites/webservices must run over https.

Supported by

If you want to easily add token-based authentication to your apps, feel free to check out Auth0’s SDKs and free plan at auth0.com/overview .

Setup

The configuration is done by means of environment variables.

Mandatory environment variables

• LW_SESSION_SECRET - The session secret used by the microservice
• LW_JWT_SECRET - The secret to sign the JSON Web Token (JWT)
• LW_SUBDOMAIN - The subdomain this microservice runs, e.g. login.yourdomain.com. All other subdomains (e.g. api.yourdomain.com) and the top-level (e.g. yourdomain.com)

Optional environment variables

• LW_COOKIE_MAXAGE - The max age of the store cookie, defaults to 10 days
• LW_PROFILE_COOKIENAME - The profile’s cookie name, defaults to profile
• LW_JWT_COOKIENAME - The JSON Web Token’s (JWT) cookie name, defaults to jwt
• LW_DYNAMIC_SCOPE - When set allows you to customize the scopes used in an authentication request, defaults to off
• LW_COOKIE_DOMAIN - The explicit cookie domain, e.g. .foo.com. If not specified this will derive from LW_SUBDOMAIN, e.g. if LW_SUBDOMAIN=login.foo.com then the cookie domain “defaults” to .foo.com. This is ok unless you have multi level subdomain for (LW_SUBDOMAIN=dev.login.foo.com). In this case you must explicitly set LW_COOKIE_DOMAIN=.foo.com as .login.foo.com would be the auto guessed value.

GitHub specific environment variables

You need to create your own GitHub OAuth application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/github/callback

• LW_GITHUB_CLIENTID - Your GitHub Client ID
• LW_GITHUB_CLIENTSECRET - Your GitHub Client Secret

Google specific environment variables

You need to create your own Google OAuth application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/google/callback

• LW_GOOGLE_CLIENTID - Your Google Client ID
• LW_GOOGLE_CLIENTSECRET - Your Google Client Secret

Facebook specific environment variables

You need to create your own Facebook login application. If LW_SUBDOMAIN=login.yourdomain.com your allowed redirects must be: https://login.yourdomain.com/facebook/callback

• LW_FACEBOOK_APPID - Your Facebook App ID
• LW_FACEBOOK_APPSECRET - Your Facebook App Secret

LinkedIn specific environment variables

You need to create your own LinkedIn OAuth2 application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/linkedin/callback

• LW_LINKEDIN_CLIENTID - Your LinkedIn Client ID
• LW_LINKEDIN_CLIENTSECRET - Your LinkedIn Client Secret

Reddit specific environment variables

You need to create your own Reddit OAuth application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/reddit/callback

• LW_REDDIT_CLIENTID - Your Reddit Client ID
• LW_REDDIT_CLIENTSECRET - Your Reddit Client Secret

Twitter specific environment variables

You need to create your own Twitter OAuth application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/twitter/callback

• LW_TWITTER_CONSUMERKEY - Your Twitter Consumer Key
• LW_TWITTER_CONSUMERSECRET - Your Twitter Consumer Secret

Mixer specific environment variables

You need to create your own Mixer OAuth Client. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/mixer/callback

• LW_MIXER_CLIENTID - Your Mixer Client ID
• LW_MIXER_CLIENTSECRET - Your Mixer Client Secret
• LW_MIXER_SCOPE - Specify which scopes the authorization request with Mixer should have. Check Mixer’s documentation for scopes.

Instagram specific environment variables

You need to create your own Instagram OAuth application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/instagram/callback

• LW_INSTAGRAM_CLIENTID - Your Instagram Client ID
• LW_INSTAGRAM_CLIENTSECRET - Your Instagram Client Secret

Spotify specific environment variables

You need to create your own Spotify OAuth application. If LW_SUBDOMAIN=login.yourdomain.com is your Authorization callback URL must be: https://login.yourdomain.com/spotify/callback

• LW_SPOTIFY_CLIENTID - Your Spotify Client ID
• LW_SPOTIFY_CLIENTSECRET - Your Spotify Client Secret

Strava specific environment variables

You need to create your own Strava OAuth application. If LW_SUBDOMAIN=login.yourdomain.com your Authorization callback URL must be: https://login.yourdomain.com/strava/callback

• LW_STRAVA_CLIENTID - Your Strava Client ID
• LW_STRAVA_CLIENTSECRET - Your Strava Client Secret

Endpoints

• /twitter - login with Twitter account (if configured through env variables)
• /facebook - login with Facebook account (if configured through env variables)
• /github - login with GitHub account (if configured through env variables)
• /google - login with Google account (if configured through env variables)
• /reddit - login with Reddit account (if configured through env variables)
• /mixer - login with Mixer account (if configured through env variables)
• /linkedin - login with LinkedIn account (if configured through env variables)
• /instagram - login with Instagram account (if configured through env variables)
• /spotify - login with Spotify account (if configured through env variables)
• /strava - login with Strava account (if configured through env variables)
• /logout - logout and clears the respective cookies

All endpoints expect the query parameters:

• success A url to redirect to in case of successful login (use encodeURIComponent for proper escaping)
• failure A url to redirect to in case of failed login (use encodeURIComponent for proper escaping)

Don’t forget to encodeURIComponent on them.

Testing

Say you deployed your login-with container with:

• correct environment variables
• properly configured services (e.g. Twitter callback)
• served via https on auth.your-domain.com

Then you can test everything by just “visiting” your login strategy with the browser, e.g. https://auth.your-domain.com/twitter. In case of success, you will be finally redirected and see the contents of your profile as JSON. In case of error, the error will be shown as JSON.

Example

Visit login-with.com. The source code is here.

Deployment with now

Note: You need a custom domain to run this microservice with now. Chrome (and maybe other browsers) explicitly prevent usage of wildcard cookies on .now.sh, which are required for this microservice to work.

1. Create your secrets for the environment variables
2. Deploy, e.g. with now

now lipp/login-with \
	-e NODE_ENV=production \
	-e LW_SUBDOMAIN=login.yourdomain.com \
	-e LW_SESSION_SECRET=@lw-session-secret \
	-e LW_JWT_SECRET=@lw-token-secret \
	-e LW_REDDIT_CLIENTID=@lw-reddit-clientid \
	-e LW_REDDIT_CLIENTSECRET=@lw-reddit-clientsecret \
	-e LW_GITHUB_CLIENTID=@lw-github-clientid \
	-e LW_GITHUB_CLIENTSECRET=@lw-github-clientsecret \
	-e LW_TWITTER_CONSUMERKEY=@lw-twitter-consumerkey \
	-e LW_TWITTER_CONSUMERSECRET=@lw-twitter-consumersecret \
	-e LW_INSTAGRAM_CLIENTID=@lw-instagram-clientid \
	-e LW_INSTAGRAM_CLIENTSECRET=@lw-instagram-clientsecret \
	--alias login.yourdomain.com

Deployment with Docker

1. Create your secrets for the environment variables
2. Deploy, e.g. with Docker

docker run lipp/login-with -p 80:3000 \
	-e NODE_ENV=production \
	-e LW_SUBDOMAIN=login.yourdomain.com \
	-e LW_SESSION_SECRET=@lw-session-secret \
	-e LW_JWT_SECRET=@lw-token-secret \
	-e LW_REDDIT_CLIENTID=@lw-reddit-clientid \
	-e LW_REDDIT_CLIENTSECRET=@lw-reddit-clientsecret \
	-e LW_GITHUB_CLIENTID=@lw-github-clientid \
	-e LW_GITHUB_CLIENTSECRET=@lw-github-clientsecret \
	-e LW_TWITTER_CONSUMERKEY=@lw-twitter-consumerkey \
	-e LW_TWITTER_CONSUMERSECRET=@lw-twitter-consumersecret \
	-e LW_INSTAGRAM_CLIENTID=@lw-instagram-clientid \
	-e LW_INSTAGRAM_CLIENTSECRET=@lw-instagram-clientsecret \