Rails render multiple pdf files to a folder - ruby-on-rails

Question

I have a controller action that renders a pdf for download.
I want to render multiple pdfs to a tmp folder ( then zip them for download )
I can generate the pdfs and present to the user but I can't figure out how to create a folder to store them in.
I'm using prawn. It has the render_file method to save it to the filesystem but I don't know what directory it is or if other users could save their pdf's to the same folder, so I need to create a uniques folder for each user then save the pdf's there.
How can I do this?
my controller action is currently
def showpdf
respond_to do |format|
format.html
format.pdf do
#items.each do |pdf|
pdf = Prawn::Document.new(page_size: "A4",margin: [0,0,0,0])
# pdf creation stuff...
# this was used previously to render one pdf to the browser
# but I need to save multiple pdf's
#send_data pdf.render, filename: 'report.pdf', type: 'application/pdf'
end
end
end

Answer 1

You will need to store all files into tmp/your-folder folder, something like this
require 'prawn'
#items.each do |item|
pdf = Prawn::Document.new
pdf.text("Lets Zip All.")
pdf.render_file('tmp/your-folder/#{item.id}.pdf')
end
and then simply use https://github.com/rubyzip/rubyzip to zip the your-folder.
require 'zip'
folder = "tmp/your-folder/"
zipfile_name = "tmp/archive.zip"
input_filenames = Dir.entries("tmp/your-folder/").select {|f| !File.directory? f}
Zip::File.open(zipfile_name, Zip::File::CREATE) do |zipfile|
input_filenames.each do |filename|
zipfile.add(filename, folder + '/' + filename)
end
zipfile.get_output_stream("myFile") { |os| os.write "myFile contains just this" }
end
Simply send the file to user. But if the PDF contains a lot of data move them to delayed jobs.
Hope this makes sense but if not please hit reply.