PDF Export

Datagrid provides you a table like structure with data:

report = MyGrid.new

report.header # => ["Group", "Name", "Activated"]
report.rows   # => [
              #      ["Steve", "Spammers", true],
              #      [ "John", "Spoilers", true],
              #      ["Berry", "Good people", false]
              #    ]
report.data   # => [ header, *rows]

You can use this data for export.

There are some gems available that can give you export.

Using Ruport

Easy way (using ruport):

require 'ruport' # gem install ruport

f = File.new("report.pdf", "w") 
f.write Ruport::Data::Table.new(:column_names =>report.header, :data => report.rows).to_pdf
f.close

Using PrawnPDF

Ruport doesn't really work with Ruby 1.9+ because of some of its PDF dependencies. It turns out PrawnPDF can easily be used to generate a report instead:

gem 'prawn'

It's best to have a base report class. I put the PDF classes under /app/prawn. You'll need to restart your app for the directory to be autoloaded.

class PdfReport < Prawn::Document
  TABLE_ROW_COLORS = ["FFFFFF","DDDDDD"]
  TABLE_FONT_SIZE = 9

  def initialize(default_prawn_options={})
    super(default_prawn_options)
    font_size 10
  end

  def header(title=nil)
    text title, size: 18, style: :bold, align: :center if title
  end
end

Then create your custom report class:

class IdentitiesPdfReport < PdfReport
  def initialize(title, header=[], rows=[])
    super()
    @header = header
    @rows = rows

    header title
    display_table
  end

  private

  def display_table
    if @rows.empty?
      text "No Identities Found"
    else
      table @rows.unshift(@header),
        header: true,
        width: bounds.width,
        row_colors: TABLE_ROW_COLORS,
        cell_style: { size: TABLE_FONT_SIZE }
    end
  end
end

Then in your controller:

respond_to do |format|
  format.html
  format.csv do
    ...
  end
  format.pdf do
    send_data IdentitiesPdfReport.new(@title, @grid.header, @grid.rows).render,
      type: "application/pdf",
      disposition: 'attachment',
      filename: "identities-#{Time.current.to_s}.pdf"
  end
end

Works a treat!

Other PDF generators

Hard way with custom formatting: https://github.com/mileszs/wicked_pdf