Accept-Encoding headers on Cloudfront serving assets from Rails 3.0.x on Heroku cedars

Question

When I use the Rails app to directly serve my assets through the Heroku cedar stack (i.e. NOT via CDN), they automatically get gzip'd. (See my previous question about why I am confused by this.)

Now I'm trying to configure Cloudfront to serve these assets, and ideally I would like them to be gzip'd. From what I read, I thought that Cloudfront would pass Accept headers to my application, so they should be serviced by gzip'd if they are supported (the same as when you make a direct request to the asset on the hero). But this is not so. Asset titles look like this:

 Age:510 Connection:keep-alive Content-Length:178045 Content-Type:text/css Date:Sun, 08 Jan 2012 18:55:13 GMT Last-Modified:Sun, 08 Jan 2012 18:42:34 GMT Server:nginx/0.7.67 Via:1.1 varnish, 1.0 7a0b4b3db0cc0d369fe1d6981bfb646a.cloudfront.net:11180 (CloudFront), 1.0 6af08f4042ec142b4b760ca4cd62041d.cloudfront.net:11180 (CloudFront) X-Amz-Cf-Id:2b205edf4e9ef000a31a0208ca68f4e15b746eb430cde2ba5cc4b7dff4ba41a76c24f43cf498be02,8d5863a42eea452f86831a02f3eb648b26fe07013b08b95950f15ef8ba275822e1eb3b7ed2550d01 X-Cache:Hit from cloudfront X-Varnish:2130919357 

There is no mention of encoding here, and when I look at a simple file, it is not gzip'd. So I'm wondering what I need to do here so that CloudView requests the gzip'd version from my application so that it can serve this for the client.

This post says that you need to manually gzip and download the file, but I do not understand why this is necessary. Firstly, this is annoying, and two, will it not request the file in the same way as my browser directly? So why not just give it the gzip'd file, as it was by default in my application?

Any advice on gzip'ng to work properly would be great. I would not have to manually gzip my files and upload them if possible.

Answer 1

Cedar submitted files DO NOT get GZipped on the stack, Cedar only serves everything that you have in the application code. See Documentation:

Since requests to Cedar applications are made directly in the server application - not proxied through an HTTP server such as nginx - any response compression should be performed within your application. For Rack Applications, this can be accomplished using the Rack :: Deflater middleware. For gzipped static assets, make sure that Rack :: Deflater loads before ActionDispatch :: Static in the middleware stack.

Therefore, gzipping your observation is either a false heading, or comes from somewhere else that. Therefore, if you just clicked files in Cloudfront, you just see the same thing.

If you are looking at servicing archived assets through the CDN, I would recommend that you look at the collision with Rails 3.1 and use the Asset pipeline. This will not only give you more control over your assets, but also give you a much simpler way to serve them through the CDN .