Untitled

Streaming CSV Download from Rails 3.2 app

class ExportsController < ApplicationController

            require 'fastercsv'

            require 'generic_agent'

            require 'generic_record'

 

        def listing

 

          @this_filepath = "../html/whatever/" << Time.now.strftime("%I:%M:%S_%d:%m:%y") << ".csv"

 

          @spawn_id = spawn(:nice => 1) do

 

            FasterCSV.open(@this_filepath, "w") do |csv|

 

              csv << [ "outbreak_id"]

            end

 

          end

 

          render :update do |page|

            page.replace_html 'export_status', :partial => 'export_status_partial'

          end

 

        end

 

  def send_export

 

    @this_filepath = params[:with]

    csv_file = File.open(@this_filepath.to_s, 'r')

 

    csv_string = ""

    csv_file.each_line do |line|

      csv_string << line

    end

 

   send_data csv_string, :filename => "export.csv",

                :type => 'text/csv; charset=iso-8859-1; header=present',

                :disposition => "attachment; filename=export.csv"

                #send_file @this_filepath.to_s, :stream => false, :type=>"text/csv", :x_sendfile=>true

 

                #send_data csv_string, :filename => export.csv

 

                #File.delete(@this_filepath.to_s)

  end

 

  def export_checker

    filename_array = params['filename'].split(///)

                @file_found = 0

                @file_ready = 0

 

                @file_size = File.size(params['filename'])

                @this_filepath = params['filename']

 

                if File.exists?(params['filename'])

                release_time = Time.now - 5.seconds

                if File.mtime(params['filename']).utc < release_time.utc

 

                @file_found = 1

                @file_ready = 1

                @file_access_time = File.mtime(params['filename'])

                @file_release_time = release_time

                @file_size = File.size(params['filename'])

 

                else

                @file_found = 1

                @file_ready = 0

                @file_size = File.size(params['filename'])

 

                end

 

                else

 

                @file_found = 0

                @file_ready = 0

                @file_size = File.size(params['filename'])

 

                end

 

    render :action => "export_checker"

  end

end

       

if @file_found == 1 && @file_ready == 1 && @file_size > 0

 

 

page.replace_html 'link_to_file', :partial => "export_ready"

if @file_release_time

page.replace_html 'notice', "<div>Completed #{@file_release_time.strftime("%I:%M:%S %A %d %B %Y")} :: file size #{@file_size.to_s}</div>"

end

 

page.visual_effect :highlight, 'link_to_file', :endcolor => '#D3EDAB'

 

elsif @file_found == 1

page.replace_html 'link_to_file', "<div> File found, but still being constructed.</div><div>#{@this_filepath.to_s}</div>"

page.visual_effect :highlight, 'link_to_file', :endcolor => '#FF9900'

else

page.replace_html 'link_to_file', "<div> File not found @file_found #{@file_found.to_s} @file_ready #{@file_ready.to_s}</div>"

page.visual_effect :highlight, 'link_to_file', :endcolor => '#FF0000'

end

       

format.csv {

    @entries = Entry.all

    @columns = ["First Name", "Last Name"].to_csv

    @filename = "entries-#{Date.today.to_s(:db)}"

 

    self.response.headers["Content-Type"] ||= 'text/csv'

    self.response.headers["Content-Disposition"] = "attachment; filename=#{@filename}"

    self.response.headers["Content-Transfer-Encoding"] = "binary"

 

    self.response_body = Enumerator.new do |y|

      @entries.each_with_index do |entry, i|

        if i == 0

          y << @columns

        end

        y << [entry.first_name, entry.last_name].to_csv

      end

    end

  }