class Author < ActiveRecord::Base
has_many :posts
has_many :posts_with_callbacks, :class_name => "Post", :before_add => :log_before_adding,
:after_add => :log_after_adding, :before_remove => :log_before_removing,
:after_remove => :log_after_removing
has_many :posts_with_proc_callbacks, :class_name => "Post",
:before_add => Proc.new {|o, r| o.post_log << "before_adding#{r.id}"},
:after_add => Proc.new {|o, r| o.post_log << "after_adding#{r.id}"},
:before_remove => Proc.new {|o, r| o.post_log << "before_removing#{r.id}"},
:after_remove => Proc.new {|o, r| o.post_log << "after_removing#{r.id}"}
has_many :posts_with_multiple_callbacks, :class_name => "Post",
:before_add => [:log_before_adding, Proc.new {|o, r| o.post_log << "before_adding_proc#{r.id}"}],
:after_add => [:log_after_adding, Proc.new {|o, r| o.post_log << "after_adding_proc#{r.id}"}]
has_many :unchangable_posts, :class_name => "Post", :before_add => :raise_exception, :after_add => :log_after_adding
attr_accessor :post_log
def after_initialize
@post_log = []
end
private
def log_before_adding(object)
@post_log << "before_adding#{object.id}"
end
def log_after_adding(object)
@post_log << "after_adding#{object.id}"
end
def log_before_removing(object)
@post_log << "before_removing#{object.id}"
end
def log_after_removing(object)
@post_log << "after_removing#{object.id}"
end
def raise_exception(object)
raise Exception.new("You can't add a post")
end
end
