# OpenProject AuthPlugins Plugin

Adds support for easy integration of OmniAuth strategy providers as a means to authenticate users in OpenProject.

## Dependencies

This plugin depends on the OpenProject Plugins plugin, so insert it into your `Gemfile.plugins` before the auth_plugins plugin itself:

    gem 'openproject-plugins', :git => 'git@github.com:opf/openproject-plugins.git', :branch => 'dev'

## Usage

    gem 'openproject-auth_plugins', :git => 'git@github.com:finnlabs/openproject-auth_plugins', :branch => 'dev'

You can use this plugin to make an authentication plugin out of an ordinary OpenProject plugin.
The first step is to [generate a new plugin](https://github.com/opf/openproject-plugins#generator) using the Plugins plugin.
Once you have done that it only takes a few additions to make it an authentication plugin.
Find your Engine class in `engine.rb`, let it extend `OpenProject::Plugin::AuthPlugin` and register the providers you want to use.

Here's an example of how that might look:

```ruby
module OpenProject::SomeAuthPlugin
  class Engine < ::Rails::Engine
    engine_name :openproject_some_auth_plugin

    include OpenProject::Plugins::ActsAsOpEngine
    extend OpenProject::Plugins::AuthPlugin # just add this ...

    register 'openproject-some_auth_plugin',
             author_url: 'http://my.site',
             requires_openproject: '>= 3.1.0pre1'

    assets %w(
      some_auth_plugin/some_provider.png
    )

    # to get #register_auth_providers:
    register_auth_providers do
      strategy :some_strategy do
        [
          {
            name: 'some_provider',
            host: 'foo.bar.baz',
            port: 999,
            #, ... more provider options
            icon: 'some_auth_plugin/some_provider.png'
          },
          {
            name: 'another_provider',
            host: 'foobar.biz',
            port: '692',
            #, ... more provider options
            display_name: 'Provider 2'
          }
        ]
      end

      strategy :another_strategy do
        [{name: 'yet_another_provider'}]
      end
    end
  end
end
```

Register each OmniAuth strategy by calling `strategy` with the strategy's name and returning the options for the providers using that strategy in the passed block.

As you can see in the first registered provider you can also give a new option called `icon`.
Using this option you can define which icon is to be rendered for the given provider.
In the example our own plugin provides the icon. In the plugin's directory it has to be placed under `app/assets/images/some_auth_plugin/some_provider.png`.

For each registered provider a button will be added to the OpenProject login screen as shown in the following example:

![OpenProject Login Screen](../screenshots/login_screen.png?raw=true "Login screen showing buttons for 6 providers.")

In this example an icon has only been defined for 'Google'.
All other providers will just show a default icon.

### Runtime Changes

All used strategies have to be known at the start of the application.
Providers, however, can change arbitrarily at runtime.
The block passed to `#strategy` is called each time an authentication request is made.