OmniAuth Fellowship One Strategy

Introduction

This library is an implementation of the OmniAuth Fellowship One 3rdparty Authentication Strategy.

This library has only been tested with Devise and OmniAuth, but there is no reason it cannot work without Devise.

Example Usage

The following example demonstrates what is required to use Devise and OmniAuth in Rails 3.x with the Fellowship One Strategy to implement a sign in that authenticates against Fellowship One.

Add the gem to the Gemfile:

gem 'omniauth-fellowshipone'

Example Devise initializer configuration (config/initializers/devise.rb):

config.omniauth :fellowship_one,
                # FellowshipOne 3rdparty Consumer Key
                '123',
                # FellowshipOne 3rdparty Consumer Secret
                '01234567-89ab-cdef-0123-4567890afbcd',
                # FellowshipOne API Endpoint with %CC in place of
                # church code
                :site => 'https://%CC.fellowshiponeapi.com'.freeze

Example Devise route configuration (config/routes.rb):

devise_for :users, :controllers => {:omniauth_callbacks => 'users/omniauth_callbacks'} do
  get 'sign_in', :to => 'users/sessions#new', :as => :new_user_session
  delete 'sign_out', :to => 'users/sessions#destroy', :as => :destroy_user_session
  get '/users/auth/:provider' => 'users/omniauth_callbacks#passthru'
end

unauthenticated do
  root :to => 'users/sessions#new'
end

Example Application Controller (app/controllers/users/application_controller.rb):

class ApplicationController < ActionController::Base
  before_filter :authenticate_user!
end

Example Users Controller (app/controllers/users/sessions_controller.rb):

class Users::SessionsController < ApplicationController
  skip_before_filter :authenticate_user!

  def new
    # sign_in is called in the callbacks controller
  end

  def destroy
    sign_out
    redirect_to new_user_session_path
  end
end

Example OmniAuth Callbacks Controller (app/controllers/users/omniauth_callbacks_controller.rb):

class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController

  def fellowship_one
    @user = User.find_for_fellowship_one(env["omniauth.auth"], current_user)

    if @user.persisted?
      flash[:notice] = I18n.t "devise.omniauth_callbacks.success", :kind => "FellowshipOne"
      sign_in_and_redirect @user, :event => :authentication
    else
      session["devise.fellowship_one_data"] = env["omniauth.auth"]
      redirect_to new_user_registration_url
    end
  end

  def passthru
    render :file => "#{Rails.root}/public/404.html", :status => 404, :layout => false
  end

end

Example User model (app/models/user.rb):

class User < ActiveRecord::Base
  devise :omniauthable

  attr_accessible :uid, :church_code, :secret, :token, :first, :last,

  def self.find_for_fellowship_one(access_token, signed_in_resource=nil)
    uid = access_token['uid']
    church_code = access_token['info']['church_code']
    token = access_token['credentials']['token']
    secret = access_token['credentials']['secret']
    last = access_token['info']['last']
    first = access_token['info']['first']

    if user = User.find_by_uid(uid)
      user.update_attributes!(:token => token,
                              :secret => secret)
    else
      user = User.create!(:uid => uid,
                          :church_code => church_code,
                          :first => first,
                          :last => last,
                          :token => token,
                          :secret => secret)
    end

    user
  end
end

Example New User Html (app/views/users/sessions/new.html.erb):

<%= form_tag(user_omniauth_authorize_path(:fellowship_one)) do %>
<input type="text" id="church_code"/>
...
<% end %>

<script type="text/javascript">
$(document).ready(function() {
  $("form").submit(function() {
    var $church_code = $("#church_code");
    /* validate church code */
    $(this).attr('action', $(this).attr('action') + "?church_code=" + escape($church_code.val()));
  });
});
</script>

kcburge / omniauth-fellowshipone