Rails 'link_to' to Download An Image Immed

问题:

I have a link_to Rails helper that downloads a wallpaper when clicked. But the image is loading in the browser instead of being downloaded immediately.

<%= link_to "1920x1080", @download.wallpapers[1].wallpaper.url %>

But at the same time I have a link_to Rails helper that downloads a screensaver of .exe format but here it works as inteded: file being downloaded immediately.

<%= link_to "720p", @download.screensavers.first.screensaver.url %>

What should I add or do so that the images will not be opened in the browser but instead be downloaded immediately?

Thanks!

回答1:

Generally, the cleanest way to do this is to set the appropriate header when sending the image:

Content-Disposition: attachment; filename=<file name.ext>

The send_file method will allow you to set this header appropriately if you're serving the file from the filesystem:

http://api.rubyonrails.org/classes/ActionController/Streaming.html#method-i-send_file

If the file is stored in your database, you can use send_data instead:

http://api.rubyonrails.org/classes/ActionController/Streaming.html#method-i-send_data

回答2:

There is an easier way to do this with the HTML5 download attribute.

<%= link_to 'Download existing avatar', @user.avatar(:original), download: "User_#{@user.id}_avatar" %>

回答3:

Instead of putting the link of the image in your tag, you can handle it in your controller. And then in your controller you can do something like

send_file @download.wallpapers[1].wallpaper.url, :type => 'image/jpeg', :disposition => 'attachment'

Read this

回答4:

Rails 3 / 4:

in routes:

get "home/download_pdf"

in controller:

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

in view:

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

回答5:

Here's a simple solution using the HTML5 download attribute with paperclip

<%= link_to item.name, item.asset.url, download: item.asset.original_filename %>