trustieforge/app/caches/attachments_cache.rb

#资源缓存
class AttachmentsCache
  class << self

    #------------班级资源缓存---------------------
    def course_attachments_cache(course_id)
      key = 'course_attachments:'+course_id.to_s
      data = Rails.cache.read(key)
      if data.nil?
        data = []
        course = Course.find(course_id)
        course.attachments.each do |attachment|
          data << {
              :id=>attachment.id,
              :filesize=>attachment.filesize,
              :downloads=>attachment.downloads,
              :author_id=>attachment.author_id,
              :created_on=>attachment.created_on,
              :is_public=>attachment.is_public,
              :is_publish=>attachment.is_publish,
              :container_id=>attachment.container_id,
              :container_type=>attachment.container_type,
          }
        end
        Rails.cache.write(key,data)
      end
      data
    end

    #增加删除type
    def update_course_attachments_cache(course_id,attachemnt_id,type,opt={})
      key = 'course_attachments:'+course_id.to_s
      data = Rails.cache.read(key)
      if data.nil?
        # data = []
        # course = Course.find(course_id)
        # course.attachments.each do |attachment|
        #   data << {
        #       :id=>attachment.id,
        #       :filesize=>attachment.filesize,
        #       :downloads=>attachment.downloads,
        #       :author_id=>attachment.author_id,
        #       :created_on=>attachment.created_on,
        #       :is_public=>attachment.is_public,
        #       :is_publish=>attachment.is_publish,
        #       :container_id=>attachment.container_id,
        #       :container_type=>attachment.container_type,
        #   }
        # end
        #
        # Rails.cache.write(key,data)
      else
        if type == 0
          #增加
          attachment = Attachment.find(attachemnt_id)
          data << {
              :id=>attachment.id,
              :filesize=>attachment.filesize,
              :downloads=>attachment.downloads,
              :author_id=>attachment.author_id,
              :created_on=>attachment.created_on,
              :is_public=>attachment.is_public,
              :is_publish=>attachment.is_publish,
              :container_id=>attachment.container_id,
              :container_type=>attachment.container_type,
          }
        elsif type == 1
          #删除
          data.each do |atta|
            if atta[:id] == attachemnt_id
              data.delete(atta)
              break
            end
          end
        else
          #修改
          attachment = Attachment.find(attachemnt_id)
          data.each_with_index do |atta,index|
            if atta[:id] == attachemnt_id
              data[index] = {
                  :id=>attachment.id,
                  :filesize=>attachment.filesize,
                  :downloads=>attachment.downloads,
                  :author_id=>attachment.author_id,
                  :created_on=>attachment.created_on,
                  :is_public=>attachment.is_public,
                  :is_publish=>attachment.is_publish,
                  :container_id=>attachment.container_id,
                  :container_type=>attachment.container_type,
              }
              break
            end
          end
        end
        Rails.cache.write(key,data)
      end
    end

  end
end