module DataMapper
module Is
# = dm-is-published
#
# This plugin makes it very easy to add different states to your models, like 'draft' vs 'live'.
# By default it also adds validations of the field value.
#
# Originally inspired by the Rails plugin +acts_as_publishable+ by fr.ivolo.us.
#
#
# == Installation
#
# # Add GitHub to your RubyGems sources
# $ gem sources -a http://gems.github.com
#
# $ (sudo)? gem install kematzy-dm-is-published
#
# NB! Depends upon the whole DataMapper suite being installed, and has ONLY been tested with DM 0.10.0 (next branch).
#
#
# == Getting Started
#
# First of all, for a better understanding of this gem, make sure you study the 'dm-is-published/spec/integration/published_spec.rb' file.
#
# ----
#
# Require +dm-is-published+ in your app.
#
# require 'dm-core' # must be required first
# require 'dm-is-published'
#
# Lets say we have an Article class, and each Article can have a current state,
# ie: whether it's Live, Draft or an Obituary awaiting the death of someone famous (real or rumored)
#
#
# class Article
# include DataMapper::Resource
# property :id, Serial
# property :title, String
# ...
#
# is :published
#
# end
#
# Once you have your Article model we can create our Articles just as normal
#
# Article.create(:title => 'Example 1')
#
#
# The instance of Article.get(1) now has the following things for free:
#
# * a :publish_status attribute with the value 'live'. Default choices are [ :live, :draft, :hidden ].
#
# * :is_live?, :is_draft? or :is_hidden? methods that returns true/false based upon the state.
#
# * :save_as_live, :save_as_draft or :save_as_hidden converts the instance to the state and saves it.
#
# * :publishable? method that returns true for models where is :published has been declared,
# but false for those where it has not been declared.
#
#
# The Article class also gets a bit of new functionality:
#
# Article.all(:draft) => finds all Articles with :publish_status = :draft
#
#
# Article.all(:draft, :author => @author_joe ) => finds all Articles with :publish_status = :draft and author == Joe
#
#
# Todo:: add more documentation here...
#
#
# == Usage Scenarios
#
# In a Blog/Publishing scenario you could use it like this:
#
# class Article
# ......
#
# is :published :live, :draft, :hidden
# end
#
# Whereas in another scenario - like in a MenuItem model for a Restaurant - you could use it like this:
#
# class MenuItem
# ......
#
# is :published :on, :off # the item is either on the menu or not
# end
#
#
# == RTFM
#
# As I said above, for a better understanding of this gem/plugin, make sure you study the 'dm-is-published/spec/integration/published_spec.rb' file.
#
#
# == Errors / Bugs
#
# If something is not behaving intuitively, it is a bug, and should be reported.
# Report it here: http://github.com/kematzy/dm-is-published/issues
#
# == Credits
#
# Copyright (c) 2008-05-07 [Kematzy at gmail]
#
# Loosely based on the ActsAsPublishable plugin by [http://fr.ivolo.us/posts/acts-as-publishable]
#
# == Licence
#
# Released under the MIT license.
module Published
##
# method that adds a basic published status attribute to your model
#
# == params
#
# * +states+ - an array of 'states' as symbols or strings. ie: :live, :draft, :hidden
#
# ==== Examples
#
#
# is :published :on, :off
#
# is :published %w(a b c d)
#
#
# @api public
def is_published(*args)
# set default args if none passed in
args = [:live, :draft, :hidden] if args.blank?
args = args.first if args.first.is_a?(Array)
# the various publish states accepted.
@publish_states = args.collect{ |state| state.to_s.downcase.to_sym }
@publish_states_for_validation = args.collect{ |state| state.to_s.downcase }
extend DataMapper::Is::Published::ClassMethods
include DataMapper::Is::Published::InstanceMethods
# do we have a :publish_status declared
if properties.any?{ |p| p.name == :publish_status }
# set default value to first value in declaration or the given value
d = properties[:publish_status].default.blank? ? @publish_states.first.to_s : properties[:publish_status].default
# set the length to 10 if missing or if shorter than 5, otherwise use the given value
l = 5 if properties[:publish_status].length.blank?
l = (properties[:publish_status].length <= 10 ? 10 : properties[:publish_status].length)
property :publish_status, String, :length => l, :default => d.to_s
else
# no such property, so adding it with default values
property :publish_status, String, :length => 10, :default => @publish_states.first.to_s
end
# create the state specific instance methods
self.publish_states.each do |state|
define_method("is_#{state}?") do
self.publish_status == state.to_s
end
define_method("save_as_#{state}") do
self.publish_status = state.to_s
save
end
end
# ensure we are always saving publish_status values as strings
before :valid? do
self.publish_status = self.publish_status.to_s if self.respond_to?(:publish_status)
end
validates_within :publish_status,
:set => @publish_states_for_validation,
:message => "The publish_status value can only be one of these values: [ #{@publish_states_for_validation.join(', ')} ]"
end
module ClassMethods
attr_reader :publish_states, :publish_states_for_validation
##
# Overriding the normal #all method to add some extra sugar.
#
# ==== Examples
#
# Article.all => returns all Articles as usual
#
# Article.all( :publish_status => :live ) => returns all Articles with :publish_status == :lve
#
# Article.all(:draft) => returns all Articles with :publish_status == :draft
#
# Article.all(:draft, :author => @author_joe ) => finds all Articles with :publish_status = :draft and author == Joe
#
#
# @api public/private
def all(*args)
# incoming can either be:
# -- nil (nothing passed in, so just use super )
# -- (Hash) => all(:key => "value") ( normal operations, so just pass on the Hash )
# -- (Symbol) => all(:draft) ( just get the symbol, )
# -- (Symbol, Hash ) => :draft, { extra options }
# -- (DataMapper somethings) => leave it alone
if args.empty?
return super
elsif args.first.is_a?(Symbol)
# set the from args Array, remove first item if Symbol, and then check for 2nd item's presence
state, options = args.shift.to_s, (args.blank? ? {} : args.first)
# puts " and state=[#{state}] and options=[#{options.class}] options.inspect=[#{options.inspect}] [#{__FILE__}:#{__LINE__}]"
return super({ :publish_status => state }.merge(options) )
elsif args.first.is_a?(Hash)
# puts "dm-is-published args.first was a HASH ] [#{__FILE__}:#{__LINE__}]"
return super(args.first)
else
# puts "dm-is-published (ELSE) [#{__FILE__}:#{__LINE__}]"
return super
end
end
end # ClassMethods
module InstanceMethods
##
# Ensuring all models using this plugin responds to publishable? with true.
#
# ==== Examples
#
# @published_model.publishable? => true
#
# @api public
def publishable?
true
end
end # InstanceMethods
module ResourceInstanceMethods
##
# Ensuring all models NOT using this plugin responds to publishable? with false.
#
# ==== Examples
#
# @unpublished_model.publishable? => false
#
# @api public
def publishable?
false
end
end #/module ResourceInstanceMethods
end # Published
end # Is
Model.append_extensions(Is::Published)
end # DataMapper