Getting rendered images to the browsers in Rails

Question

I am writing a Rails app that processes data into a graph (using Scruffy). I am wondering how can I render the graph to a blog/string and then send the blog/string directly to the the browser to be displayed (without saving it to a file)? Or do I need to render it, save it to a file, then display the saved image file in the browser?

Answer 1

I think you will be able to use send_data for this purpose:

send_data data_string, :filename => 'icon.jpg', :type => 'image/jpeg', :disposition => 'inline'

If you put this in a controller action - say show on a picture controller, then all you need do is include the following in your view (assuming RESTful routes):

<%= image_tag picture_path(@picture) %>

Answer 2

I wonder if sending direct to the browser is the best way? If there is the possibility that users will reload the page would this short circuit any cache possibilities? I ask because I really don't know.

Answer 3

"If there is the possibility that users will reload the page would this short circuit any cache possibilities?"

No - whether you're serving from a file system or send_data doesn't matter. The browser is getting the data from your server anyway. Just make sure you've got your HTTP caching directives sorted out.