gistfile1.rb

  def oauth
    OAuth::Consumer.new(
      consumer_key,
      consumer_secret,
        {
          :site                 => 'https://api.login.yahoo.com', 
          :scheme               => :query_string, 
          :http_method          => :get, 
          :request_token_path   => '/oauth/v2/get_request_token', 
          :access_token_path    => '/oauth/v2/get_token', 
          :authorize_path       => '/oauth/v2/request_auth',
          
    })
  end
  
  def oauth_api
    OAuth::Consumer.new(
        consumer_key,
        consumer_secret,
        {
          :site                 => 'http://social.yahooapis.com', 
          :scheme               => :header, 
          :realm                => 'yahooapis.com', 
          :http_method          => :get,
          :request_token_path   => '/oauth/v2/get_request_token', 
          :access_token_path    => '/oauth/v2/get_token', 
          :authorize_path       => '/oauth/v2/request_auth'
    })
  end

### To authorize (note that oauth is the method above:

@request_token = oauth.get_request_token(
        { :oauth_callback => "http://example.com/callback" } )

session['yahoo_rtoken'] = @request_token.token
session['yahoo_stoken'] = @request_token.secret
redirect_to @request_token.authorize_url


# callback

@request_token = OAuth::RequestToken.new( oauth, session['yahoo_rtoken'], session['yahoo_stoken'] )
 @access_token = @request_token.get_access_token({ :oauth_verifier => params[:oauth_verifier] })
@access_token.consumer = oauth_api
session['yahoo_atoken'] = nil
session['yahoo_stoken'] = nil

## Example once you are authorized:

@access_token = OAuth::AccessToken.new( oauth_api, current_user.yahoo_atoken, current_user.yahoo_stoken )
    guid_response = @access_token.get('/v1/me/guid')
    guid = XMLObject.new(guid_response.body).value
    response = @access_token.get("/v1/user/#{guid}/contacts?count=max")