firebase-auth-rails

A gem for handling Firebase authentication in Ruby on Rails 5+.

This project was inspired and influenced by firebase_id_token and knock. Thanks to the authors of those projects!

Current Development Status

This is a beta version only
The only feature avaialable at this time is "login"; Firebase's user creation is not supported at this time.

Installation

Add this line to your application's Gemfile:

gem 'firebase-auth-rails'

And then execute:

$ bundle

Or install it yourself as:

$ gem install firebase-auth-rails

Setup

NOTE: A lot if not all of the following can and should be automated in a generic "install" generator, in the future. For now, though there is some setup you'll have to do yourself...

First, create a file config/initializers/firebase_auth_initializer.rb, and add the following. You'll need to deal with setting up Redis and replacing your project ID, and so on

FirebaseIdToken.configure do |config|
  config.redis = Redis.new
  config.project_ids = ['firebase_project_id']
end

You need to have a uid string column, so go ahead and generate a migration for that

rails g migration AddUidToUsers uid:string

You should end up with a file db/migrate/xxxxxxxxxxxxxx_add_uid_to_users.rb, with contents something like

class AddUidToUsers < ActiveRecord::Migration[5.1]
  def change
    add_column :users, :uid, :string
  end
end

Run the migrations

rails db:migrate

In your ApplicationController, include the Authenticable module

include Firebase::Auth::Authenticable

Now you could, for instance, use a before_action to perform authentication before any controller action

before_action :authenticate_user

Test it out!

Assuming everything is set up correctly at this point, you should be able to access the current user!

current_user.user_name
# => yamada

Example Code

Below is all the code you need to implement a very basic authentication system, including sign up.

app/controllers/application_controller

class ApplicationController < ActionController::Base
  # We need to include the gem's main module to do anything...
  #
  include Firebase::Auth::Authenticable

  # Let's assume everything is protected by performing the `authenticate_user`
  # method before any controller action. We can skip this where needed.
  #
  before_action :authenticate_user
end

api/controllers/users/registrations_controller

module Users
  class RegistrationsController < ApplicationController
    # We don't want to try and authenticate a user who is trying to sign up!
    # This is how we skip the authentication, like mentioned earlier.
    #
    skip_before_action :authenticate_user

    # TODO: Not sure exactly what is meant to be going on here
    # I assume it's expecting a POST request from Firebase?
    #
    # Hopefully someone can come in and clear this up better in the future.
    #
    def create
      raise ArgumentError, 'BadRequest Parameter' if payload.blank?
      user = User.create!(sign_up_params.merge(uid: payload['sub']))
      render json: user, serializer: V1::AuthSerializer, status: :ok
    end

    private

    def sign_up_params
      params.require(:registration).permit(:user_name, :display_name)
    end

    def token_from_request_headers
      request.headers['Authorization']&.split&.last
    end

    def token
      params[:token] || token_from_request_headers
    end

    def payload
      @payload ||= FirebaseIdToken::Signature.verify token
    end
  end
end

Testing

Run migrations for Rails test dummy

cd test/dummy/
bin/rails migrate

FirebaseIdToken setup: see this link for details
Run the tests w/ Rake!

rake test

Contributing

We welcome PRs!

License

The gem is available as open source under the terms of the MIT License.