Rafael Madeira rafaelmadeira

Polymorphic Associations reversed

It's pretty easy to do polymorphic associations in Rails: A Picture can belong to either a BlogPost or an Article. But what if you need the relationship the other way around? A Picture, a Text and a Video can belong to an Article, and that article can find all media by calling @article.media

This example shows how to create an ArticleElement join model that handles the polymorphic relationship. To add fields that are common to all polymorphic models, add fields to the join model.

Polymorphic Associations reversed

It's pretty easy to do polymorphic associations in Rails: A Picture can belong to either a BlogPost or an Article. But what if you need the relationship the other way around? A Picture, a Text and a Video can belong to an Article, and that article can find all media by calling @article.media

This example shows how to create an ArticleElement join model that handles the polymorphic relationship. To add fields that are common to all polymorphic models, add fields to the join model.

Todo.rb

Todo.rb is a simple command-line tool for managing todos. It's minimal, straightforward, and you can use it with your favorite text editor.

Getting Started

Todo.rb doesn't require any third-party gems so you can copy the file anywhere and use it as long as it's executable:

	class ApplicationController < ActionController::Base
	helper :all # include all helpers, all the time
	protect_from_forgery # See ActionController::RequestForgeryProtection for details

	# Scrub sensitive parameters from your log
	# filter_parameter_logging :password

	before_filter :log_page_view, :except => [:destroy]

	private

	# Simple bijective function
	# Basically encodes any integer into a base(n) string,
	# where n is ALPHABET.length.
	# Based on pseudocode from http://stackoverflow.com/questions/742013/how-to-code-a-url-shortener/742047#742047

	ALPHABET =
	"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".split(//)
	# make your own alphabet using:
	# (('a'..'z').to_a + ('A'..'Z').to_a + (0..9).to_a).shuffle.join

	require 'rubygems'
	require 'sinatra'
	require 'redis'

	# To use, simply start your Redis server and boot this
	# example app with:
	# ruby example_note_keeping_app.rb
	#
	# Point your browser to http://localhost:4567 and enjoy!
	#