ruby-on-rails – Ruby中的存储库或网关模式

这是我做的：

require 'active_support/core_ext/module/attribute_accessors'

class GenericRepository

  def initialize(options = {})
    @scope = options[:scope]
    @association_name = options[:association_name]
  end

  def self.set_model(model,options = {})
    cattr_accessor :model
    self.model = model
  end

  def update(record,attributes)
    check_record_matches(record)
    record.update_attributes!(attributes)
  end

  def save(record)
    check_record_matches(record)
    record.save
  end

  def destroy(record)
    check_record_matches(record)
    record.destroy
  end

  def find_by_id(id)
    scoped_model.find(id)
  end

  def all
    scoped_model.all
  end

  def create(attributes)
    scoped_model.create!(attributes)
  end

private

  def check_record_matches(record)
    raise(ArgumentError,"record model doesn't match the model of the repository") if not record.class == self.model
  end

  def scoped_model
    if @scope
      @scope.send(@association_name)
    else
      self.model
    end
  end

end

然后你可以有一个Post存储库.

class PostRepository < GenericRepository

  set_model Post

  # override all because we also want to fetch the comments in 1 go.
  def all
    scoped_model.all(:include => :comments)
  end

  def count()
    scoped_model.count
  end

end

只需在您的控制器中在before_filter或初始化或任何地方实例化它.在这种情况下,我将其范围限定为current_user,以便它仅获取这些记录并仅为当前用户自动创建帖子.

def initialize
  @post_repository = PostRepository.new(:scope => @current_user,:association_name => 'posts')
end

def index
  @posts = @post_repository.all
  respond_with @posts,:status => :ok
end

我遇到了https://github.com/bkeepers/morphine这是一个很小的DI框架.它可能适合你:)但DI不是ruby中使用频繁的模式.此外,我实例化我的repos,以便将它们范围限定为当前用户或其他东西.

我正在努力找到正确的方法去做你所要求的事情,并且如果我找到的话就做一些关于它的文章.但就目前来说,已经足够在持久性和稳定性之间进行彻底切割.我的控制员.如果这样做得当,以后切换到不同的系统将不会是一个大麻烦.或者添加缓存等.