applicake/doorkeeper — pull request #249 by tsov (2013-06-25 13:44:00+00:00)
Title: Added Assertion Flow

Here a simple implementation for an Assertion Flow for Doorkeeper.

This lets you define a method to authenticate users coming from 3rd Party applications like facebook, twitter, etc.

__Example:__

```ruby
Doorkeeper.configure do
resource_owner_from_assertion do
facebook = URI.parse('https://graph.facebook.com/me?access_token=' + params[:assertion])
response = Net::HTTP.get_response(facebook)
user_data = JSON.parse(response.body)
User.find_by_facebook_id(user_data['id'])
end
end
```