OmniAuth CAS Strategy

This is a OmniAuth 2.1+ compatible port of the previously available OmniAuth CAS strategy that was bundled with OmniAuth 0.3.

• View the documentation
• Changelog

Add this line to your application's Gemfile:

gem 'omniauth-cas'

And then execute:

$ bundle

Or install it yourself as:

$ gem install omniauth-cas

Use like any other OmniAuth strategy:

Rails.application.config.middleware.use OmniAuth::Builder do
  provider :cas, host: 'cas.yourdomain.com'
end

OmniAuth CAS requires at least one of the following two configuration options:

• url - Defines the URL of your CAS server (i.e. https://example.org:8080)
• host - Defines the host of your CAS server (i.e. example.org).

Other configuration options:

• port - The port to use for your configured CAS host. Optional if using url.

• ssl - TRUE to connect to your CAS server over SSL. Optional if using url.

• service_validate_url - The URL to use to validate a user. Defaults to '/serviceValidate'.

• callback_url - The URL custom URL path which CAS uses to call back to the service. Defaults to /users/auth/cas/callback.

• logout_url - The URL to use to logout a user. Defaults to '/logout'.

• login_url - Defines the URL used to prompt users for their login information. Defaults to /login If no host is configured, the host application's domain will be used.

• uid_field - The user data attribute to use as your user's unique identifier. Defaults to 'user' (which usually contains the user's login name).

• ca_path - Optional when ssl is true. Sets path of a CA certification directory. See Net::HTTP for more details.

• disable_ssl_verification - Optional when ssl is true. Disables verification.

• merge_multivalued_attributes - When set to true returns attributes with multiple values as arrays. Defaults to false and returns the last value as a string.

• on_single_sign_out - Optional. Callback used when a CAS 3.1 Single Sign Out request is received.

• fetch_raw_info - Optional. Callback used to return additional "raw" user info from other sources.

  provider :cas,
    fetch_raw_info: Proc.new { |strategy, opts, ticket, user_info, rawxml|
      return {} if user_info.empty? || rawxml.nil? # Auth failed
  
      extra_info = ExternalService.get(user_info[:user]).attributes
      extra_info.merge!({'roles' => rawxml.xpath('//cas:roles').map(&:text)})
      extra_info
    }

Configurable options for values returned by CAS:

• uid_key - The user ID data attribute to use as your user's unique identifier. Defaults to 'user' (which usually contains the user's login name).
• name_key - The data attribute containing user first and last name. Defaults to 'name'.
• email_key - The data attribute containing user email address. Defaults to 'email'.
• nickname_key - The data attribute containing user's nickname. Defaults to 'user'.
• first_name_key - The data attribute containing user first name. Defaults to 'first_name'.
• last_name_key - The data attribute containing user last name. Defaults to 'last_name'.
• location_key - The data attribute containing user location/address. Defaults to 'location'.
• image_key - The data attribute containing user image/picture. Defaults to 'image'.
• phone_key - The data attribute containing user contact phone number. Defaults to 'phone'.

Given the following OmniAuth 0.3 configuration:

provider :CAS, cas_server: 'https://cas.example.com/cas/'

Your new settings should look similar to this:

provider :cas,
         host:      'cas.example.com',
         login_url: '/cas/login',
         service_validate_url: '/cas/serviceValidate'

If you encounter problems with SSL certificates you may want to set the ca_path parameter or activate disable_ssl_verification (not recommended).

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Added some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request

Special thanks go out to the following people

• Phillip Aldridge (@iterateNZ) and JB Barth (@jbbarth) for helping out with Issue #3
• Elber Ribeiro (@dynaum) for Ubuntu SSL configuration support
• @rbq for README updates and OmniAuth 0.3 migration guide