Rails 3 Engine for using the Houdini Mechanical Turk API
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This ruby gem is a Rails Engine for using the Houdini Mechanical Turk API. It provides easy integration into your models and sets up the necessary controllers to receive answers posted back to your app from Houdini.

Check out the Houdini Documentation for more info about the API.

Installation (Rails 3.x)

Add the gem to your Gemfile

gem 'houdini'

Configure a few constants in config/initializers/houdini.rb

Houdini.setup :sandbox, :api_key => 'YOUR_API_KEY', :app_host => 'https://your-app-domain.com'

You may want to configure Houdini differently for each of you environments.

Example Usage

Request a beta account at http://houdiniapp.com to gain access to the Houdini Blueprint Editor.

Setup Houdini in your ActiveRecord model:

class Post < ActiveRecord::Base
  include Houdini::Model

  houdini :image_moderation,
    :input => {
      :image_url => :image_url,                          # call the input_url method for
      :image_caption => lambda{ self.caption.titleize }, # use a lambda, called in the model's context
      :image_size => "100x100"                           # just send this string 
    :on => :after_create,
    :on_task_completion => :process_image_moderation_answer

  def process_image_moderation_answer(params, verbose={})
    update_attribute :flagged => params[:category] == 'flagged'


houdini(blueprint, options)

  • blueprint - The name of the Houdini blueprint to use. Must be symbol or string.
  • options - Hash of options to use.


  • :input - Required. Hash: any task specific info needed to populate your blueprint. Keys must match the blueprint's required input, and values must a Symbol of the method to call, a lambdas/procs to be called in the model's context, or just a value to send along.
  • :on_task_completion - Method that should be called when the answer is posted back to your app. Can be a symbol or a lambda/proc. The method will be called with a hash of the returned output from Houdini.
  • :on - Name of a callback to use in order to trigger the submission to Houdini. Must be a symbol/string. If you don't want to use a callback, call the model instance's houdini_submit_#{blueprint}! method, where blueprint is the first argument you provided for the houdini method.
  • :after_submit - Method that should be called after submitting the task to Houdini. Can be a symbol or a lambda/proc.
  • :id_method - Method to get an identifier for the object. It is id by default, but you may want to use to_param with your app. Can be a symbol or lambda/proc. Use this in conjunction with :finder.
  • :finder - Method by which to find the model by an identifier. It is find by default. Can be a symbol or lambda/proc. Use this in conjunction with :id_method.

Example Application

An example Rails 3.2 & Mongoid application can be found here: https://github.com/chrisconley/houdini-rails-32



MIT License. Copyright 2013 Houdini Inc. http://houdiniapi.com