How to enable compression in Ruby on Rails? - ruby-on-rails

Question

I posted a similar question here
Serving Compressed Assets in Heroku with Rack-Zippy
but decided to give up on that service, since I couldn't get it to work.
I ran PageSpeed Insights on my website to determine the speed of my website.
The most important suggestion I received was to Enable Compression.
Compressing resources with gzip or deflate can reduce the number of bytes sent over the network.
Enable compression for the following resources to reduce their transfer size by 191.2KiB
(74% reduction).
I've followed the instructions on this website
https://developers.google.com/speed/docs/insights/EnableCompression
and it says to consult the documentation for your web server on how to enable compression:
I've used this website to find out my web server
http://browserspy.dk/webserver.php
It turns out that my web server is WEBrick.
The PageSpeed Insights Page only lists the following 3 servers
Apache: Use mod_deflate
Nginx: Use ngx_http_gzip_module
IIS: Configure HTTP Compression
I've searched for documentation on gzip compression for WEBrick servers but couldn't find anything.
I've searched for how to enable compression in Rails and couldn't find anything. That's why I'm asking here.
I've tried using Rack Zippy but gave up on it.
Right now, I don't even know where to begin. My first step, is finding out what I should do.
Edit
I followed Ahmed's suggestion of using Rack::Deflator
I confirmed that I had it by running
rake middleware
=> use Rack::Deflator
and then
git add .
git commit -m '-'
git push heroku master
Unfortunately PageSpeed still says it needs to be compress. I confirmed that by going into Developer Tools << Network Settings and refreshing the page. Size and content were virtually identical for every resource meaning the files are not compressed.
Is there something wrong with one of my files?
Thank you for your help.
Here is my full config/application.rb file
require File.expand_path('../boot', __FILE__)
require 'rails/all'
Bundler.require(*Rails.groups)
module AppName
class Application < Rails::Application
config.middleware.use Rack::Deflater
config.assets.precompile += %w(*.png *.jpg *.jpeg *.gif)
config.exceptions_app = self.routes
config.cache_store = :memory_store
end
end
If there is a problem, the source is likely over there, right?
Do I need to install the deflator gem?

Answer 1

Enable compression
Add it to config/application.rb:
module YourApp
class Application < Rails::Application
config.middleware.use Rack::Deflater
end
end
Source: http://robots.thoughtbot.com/content-compression-with-rack-deflater

Answer 2

Rack::Deflater should work if you use insert_before (instead of "use"), to place it near the top of the middleware stack, prior to any other middleware that might send a response. .use places it at the bottom of the stack. On my machine the topmost middleware is Rack::Sendfile. So I would use:
config.middleware.insert_before(Rack::Sendfile, Rack::Deflater)
You can get the list of middleware in order of loading by doing rake middleware from the command line.
Note: A good link for insert_before vs Use in middleware rack

Answer 3

As per the author of Rack::Deflater it should be placed after ActionDispatch::Static in a Rails app. The reasoning is that if your app is also serving static assets (like on Heroku, for example), when assets are served from disk they are already compressed. Inserting it before would only end up in Rack::Deflater attempting to re-compress those assets. Therefore as a performance optimisation:
# application.rb
config.middleware.insert_after ActionDispatch::Static, Rack::Deflater