file download link in rails

If the files are static (meaning they don't change), place them in the public folder.

Then you can download like

<a href="file.pdf" download>PDF</a>

or with ERB

<%= link_to 'PDF', 'file.pdf', download: '' %>

and to give the file another name for downloading, just pass that name to the download option

<%= link_to 'PDF', 'file.pdf', download: 'data' %>

This will download the file as data.pdf instead of file.pdf.

Rails 4:

in routes:

get "home/download_pdf"

in controller (already have pdf):

def download_pdf
  send_file(
    "#{Rails.root}/public/your_file.pdf",
    filename: "your_custom_file_name.pdf",
    type: "application/pdf"
  )
end

in controller (need to generate pdf):

require "prawn"
class ClientsController < ApplicationController

  def download_pdf
    client = Client.find(params[:id])
    send_data generate_pdf(client),
              filename: "#{client.name}.pdf",
              type: "application/pdf"
  end

  private

  def generate_pdf(client)
    Prawn::Document.new do
      text client.name, align: :center
      text "Address: #{client.address}"
      text "Email: #{client.email}"
    end.render
  end
end

in view:

<%= link_to 'Download PDF', home_download_pdf_url %>

Rails 3

The way to do it:

def download
  send_data pdf,
    :filename => "abc.pdf",
    :type => "application/pdf"
end

You should go to this alternative

Rails < 3

File in public folder

This may the the answer to you: How to download a file from rails application

You should place your file in public folder, that is the trick.

Should work when the file is placed correctly.

Let me know if you can't move your file to public folder.

Download via controller

Create a controller with a downlaod action and link_to it

  def download
    send_file '/assets/data/abc.pdf', :type=>"application/pdf", :x_sendfile=>true
  end

Rails 4:

in routes:

get "home/download_pdf"

in controller (already have pdf):

def download_pdf
  send_file(
    "#{Rails.root}/public/your_file.pdf",
    filename: "your_custom_file_name.pdf",
    type: "application/pdf"
  )
end

in controller (need to generate pdf):

require "prawn"
class ClientsController < ApplicationController

  def download_pdf
    client = Client.find(params[:id])
    send_data generate_pdf(client),
              filename: "#{client.name}.pdf",
              type: "application/pdf"
  end

  private

  def generate_pdf(client)
    Prawn::Document.new do
      text client.name, align: :center
      text "Address: #{client.address}"
      text "Email: #{client.email}"
    end.render
  end
end

in view:

<%= link_to 'Download PDF', home_download_pdf_url %>

you can simply call your controller action like this

<%= link_to "Download", download_file_path, class: "btn btn-sm btn-default", target: "_blank" %>

and in your controller

def download_file
 redirect_to paperclip_attachment.file.url
end