Question

How can I render send to a client a file (PDF, CSV, etc) without render this file?

For example, imagine a Students controller (created using scaffold), we have ‘new’ form and ‘create’ action:

  def new
    @student = Student.new
    respond_to do |format|
      format.html # new.html.erb
    end
  end

  def create
    @student = Student.new(params[:student])
    respond_to do |format|
      if @student.save
        flash[:notice] = 'Student created'
        format.html { redirect_to(@student) }
      else
        format.html { render :action => "new" }
      end
    end
  end

When a student is successfully created it will redirect to ‘show’ template. That is OK!
But I need to send to client -for example- a PDF file and then render ‘show’ action.

This PDF file is like a creation receipt for client.

Extra info: now use Prawn to make PDF and sending to client by code like this:

    respond_to do |format|
      format.pdf { render :layout => false }
    end

In brief, I need get filled form, create student, send PDF to browser (as a creation receipt) and render ‘show’ action to display student created.

Thank you very much.

Answer 1

Here is my solution using wicked_pdf.

This creates the pdf but doesn’t download it. Saves PDF to a file. Saves the link in the database, rerenders the view with the link displayed (view is displaying the @plan).

    # create a unique PDF filename
    pdf_uuid = UUIDTools::UUID.timestamp_create().to_s
    pdf_uuid_filename = Rails.root.join('public/pdf', "#{pdf_uuid}.pdf").to_s

    # create a pdf but don't display it
    pdf_file = render_to_string :pdf => pdf_uuid_filename, 
                                :template  => 'plans/show.pdf.erb' ,
                                :layout    => 'pdf',
                                :save_only => true
    # save to a file
    File.open(pdf_uuid_filename, 'wb') do |file|
      file << pdf_file
    end
    # create full URL path to created file  
    @plan.url = request.url[0, request.url.index("plans")] +  'pdf/' + CGI::escape("#{pdf_uuid}.pdf")
    @plan.save!
    # render the page again with the link being displayed
    redirect_to :back