datamapper-associations.rb

gistfile1.rb

require 'rubygems'
require 'sinatra'
require 'dm-core'
require 'dm-migrations'
require 'dm-sqlite-adapter'

DataMapper::setup(:default, "sqlite3://#{Dir.pwd}/todo.db")

class Tag
	include DataMapper::Resource
	property	:id, Serial
	property	:title, String
	belongs_to	:todo
end


class Todo
	include DataMapper::Resource	
	property	:id, Serial
	property	:title, String
	
	has n, :tag
end

DataMapper.auto_migrate!

get '/' do
	
	# create and save a new todo
	@newtodo = Todo.create(:title => 'washing up')
	@newtodo.save
	
	
	# find the todo by title
	@todo = Todo.first(:title => 'washing up')
	# add some tags to it
	@todo.tag.create(:title => 'hassle')
	@todo.tag.create(:title => 'boring')
	
	# list everything
	output = " "
	Todo.all.each do |t|
		output << "Title: #{t.title} <br />"
		output << "tags: "
		t.tag.all.each do |thetag|
			output << " #{thetag.title}, "
		end
	end
	
	return output
		
end