socialforge/app/controllers/zipdown_controller.rb

#coding=utf-8

class ZipdownController < ApplicationController
  #查找项目（课程）
  before_filter :find_project_by_bid_id, :only => [:assort]
  #检查权限
  #勿删 before_filter :authorize, :only => [:assort,:download_user_homework]
  ## 200M
  MAX_DOWN_SIZE = 2000 * 1024 * 1024

  include ZipService

  #统一下载功能
  def download
    if User.current.logged?
      begin
        if params[:base64file]
          file = decode64(params[:base64file])
          send_file "#{OUTPUT_FOLDER}/#{file}", :filename => filename_for_content_disposition(file), :type => detect_content_type(file)
        else
          send_file "#{OUTPUT_FOLDER}/#{params[:file]}", :filename => filename_for_content_disposition(params[:filename]), :type => detect_content_type(params[:file])
        end
      rescue => e
        render file: 'public/no_file_found.html'
      end
    else
      render_403
    end
  end

  #一个作业下所有文件打包下载，只有admin和课程老师有权限
  def assort
    if params[:obj_class] == "Bid"
      bid = Bid.find params[:obj_id]
      #render_403 if User.current.allowed_to?(:as_teacher,bid.courses.first)
      zipfile = checkfileSize(bid.homeworks) {
        zip_bid bid
      }
    elsif params[:obj_class] == "HomeworkCommon"
      homework = HomeworkCommon.find params[:obj_id]
      render_403 if User.current.allowed_to?(:as_teacher,homework.course)
      zipfile = checkfileSize(homework.student_works) {
        zip_homework_common homework
      }
    elsif params[:obj_class] == "Work"
      contest_work = Work.find params[:obj_id]
      render_403 if User.current.admin_of_contest?(contest_work.contest)
      zipfile = checkfileSize(contest_work.contestant_works) {
        zip_contest_work contest_work
      }
    else
      logger.error "[ZipDown#assort] ===> #{params[:obj_class]} unKown !!"
    end
    respond_to do |format|
      format.json {
        render json: zipfile.to_json
      }
    end
  end

  #下载某一学生的作业的所有文件
  def download_user_homework
    homework = HomeworkAttach.find params[:homework]
    if User.current.admin? || User.current.member_of_course?(homework.bid.courses.first)
      if homework != nil
        unless homework.attachments.empty?
          zipfile = zip_homework_by_user homework
          filename = ((homework.user.user_extensions.nil? || homework.user.user_extensions.student_id.nil?) ? "" : homework.user.user_extensions.student_id) +
            "_" + homework.user.show_name +
            "_" + homework.name + ".zip"
          send_file zipfile.file_path, :filename => filename_for_content_disposition(filename), :type => detect_content_type(zipfile.file_path) if(zipfile)
        else
          render file: 'public/no_file_found.html'
        end
      else
        render file: 'public/file_not_found.html'
      end
    else
      render_403
    end
  #rescue => e
  #  render file: 'public/file_not_found.html'
  end

  private
  #通过作业Id找到项目（课程）
  def find_project_by_bid_id
    obj_class = params[:obj_class]
    obj_id = params[:obj_id]
    obj = obj_class.constantize.find(obj_id)
    case obj.class.to_s.to_sym
      when :Bid
        @project = obj.courses[0]
    end
  end

  def checkfileSize(works)
    file_count = 0
    file_size = 0
    works.each do |work|
      file_count += work.attachments.count
      work.attachments.each do |attach|
        file_size += attach.filesize
      end
    end

    if file_size > MAX_DOWN_SIZE
      {err: -1, message: 'file size to large'}
    elsif file_count > 0
      yield if block_given?
    else
      {err: -2, :message => "no file"}
    end
  end

end