module DeveloperProjectsAssociationExtension
def find_most_recent
find(:first, :order => "id DESC")
end
end
module DeveloperProjectsAssociationExtension2
def find_least_recent
find(:first, :order => "id ASC")
end
end
class Developer < ActiveRecord::Base
has_and_belongs_to_many :projects do
def find_most_recent
find(:first, :order => "id DESC")
end
end
has_and_belongs_to_many :projects_extended_by_name,
:class_name => "Project",
:join_table => "developers_projects",
:association_foreign_key => "project_id",
:extend => DeveloperProjectsAssociationExtension
has_and_belongs_to_many :projects_extended_by_name_twice,
:class_name => "Project",
:join_table => "developers_projects",
:association_foreign_key => "project_id",
:extend => [DeveloperProjectsAssociationExtension, DeveloperProjectsAssociationExtension2]
has_and_belongs_to_many :projects_extended_by_name_and_block,
:class_name => "Project",
:join_table => "developers_projects",
:association_foreign_key => "project_id",
:extend => DeveloperProjectsAssociationExtension do
def find_least_recent
find(:first, :order => "id ASC")
end
end
has_and_belongs_to_many :special_projects, :join_table => 'developers_projects', :association_foreign_key => 'project_id'
has_many :audit_logs
validates_inclusion_of :salary, :in => 50000..200000
validates_length_of :name, :within => 3..20
before_create do |developer|
developer.audit_logs.build :message => "Computer created"
end
def log=(message)
audit_logs.build :message => message
end
end
class AuditLog < ActiveRecord::Base
belongs_to :developer
end
DeveloperSalary = Struct.new(:amount)
class DeveloperWithAggregate < ActiveRecord::Base
self.table_name = 'developers'
composed_of :salary, :class_name => 'DeveloperSalary', :mapping => [%w(salary amount)]
end
class DeveloperWithBeforeDestroyRaise < ActiveRecord::Base
self.table_name = 'developers'
has_and_belongs_to_many :projects, :join_table => 'developers_projects', :foreign_key => 'developer_id'
before_destroy :raise_if_projects_empty!
def raise_if_projects_empty!
raise if projects.empty?
end
end