readme.md

HOW TO USE

1. put these codes in Ruby on Rails application.

module AssociationsForIncludes
  # As follows or paste codes here.
  #require 'associations_for_includes'
end

ActiveRecord::Base.send(:extend, AssociationsForIncludes)

2. call the method from ActiveRecord model.

Hoge.associations_for_includes

associations_for_includes.rb

def associations_for_includes(recursive: true, except: nil, _breadcrumb: [])
  _breadcrumb << self.class_name

  self.reflect_on_all_associations.map do |association_reflection|
    association_name = association_reflection.name
    class_name = association_reflection.class_name
    next if _breadcrumb.include?(class_name)
    next if association_reflection.options.has_key?(:polymorphic)

    case except
    when Regexp
      next if class_name =~ except
    when String, Hash
      next if class_name == except.to_s
    end

    # when depth:1
    next association_name unless recursive

    # when recursive
    recursive_associations = class_name.constantize.associations_for_includes(recursive: recursive, except: except, _breadcrumb: _breadcrumb)
    if recursive_associations.any?
      { association_name => recursive_associations }
    else
      association_name
    end
  end.compact
end

不正な関連があるとエラーが出るので、それを検知するためにも使える