Generate table in pdf with prawn

Question

I have successfully generated pdf file using prawn pdf gem inside the controller , but I want to separate class files and call the method of the class to make the controller code look clean. Here is my in-controller method

  def download_pdf
if Subscriber.count<50
  addSubscribers()
else
  @subscribers=Subscriber.all.order("name ASC")
end
  respond_to do |format|
    format.pdf do
      pdf = Prawn::Document.new
      table_data = Array.new
      table_data << ["Name","E-mail","Phone"]
      @subscribers.each do |p|
        table_data << [p.name, p.email,p.phone]
      end
      pdf.table(table_data, :width => 500, :cell_style => { :inline_format => true })
      send_data pdf.render, filename: 'test.pdf', type: 'application/pdf', :disposition => 'inline'
    end
  end

end

But when I try to use the following code->

def download_pdf
  @subscribers=Subscriber.all.order("name ASC")
  PdfCreator.new(@subscribers)
end

And the PdfCreator class is ->

    class PdfCreator

  def initialize(subscribers)
    @subs=subscr
    download_pdf()
  end

  def download_pdf()
      pdf = Prawn::Document.new
      table_data = Array.new
      table_data << ["Name","E-mail","Phone"]
      @subs.each do |p|
        table_data << [p.name, p.email,p.phone]
      end
      pdf.table(table_data, :width => 500, :cell_style => { :inline_format => true })
    send_data pdf.render, filename: 'test.pdf', type: 'application/pdf', :disposition => 'inline'
  end

end

respond to is not resolving as a method. I found some codes on generating pdf from an outside class but only for normal texts not for tables- Any help regarding how to do it for tables , that will be a great help

Answer 1

send_data is a controller-level method, and won't work inside your custom class, and the respond_to might be needed for your route to respond appropriately.

Let's try keeping what's needed in the controller and extract only PDF-generating logic to the new PdfCreator class:

def download_pdf
  @subscribers=Subscriber.all.order("name ASC")

  respond_to do |format|
    format.pdf do
      pdf = PdfCreator.new(@subscribers)
      send_data pdf.render, filename: 'test.pdf', type: 'application/pdf', disposition: 'inline'
    end
  end
end


class PdfCreator
  def initialize(subscribers)
    @subs=subscribers
  end

  def render()
    pdf = Prawn::Document.new
    table_data = Array.new
    table_data << ["Name","E-mail","Phone"]
    @subs.each do |p|
      table_data << [p.name, p.email,p.phone]
    end
    pdf.table(table_data, :width => 500, :cell_style => { inline_format: true })
    pdf.render
  end
end