How to enable gzip compression on Heroku Cedar (Python/Flask/Gunicorn)

Question

How do I enable GZIP compression on the new Heroku Cedar stack? This is straight from their site:

Since requests to Cedar apps are made directly to the application server – not proxied through an HTTP server like nginx – any compression of responses must be done within your application. For Rack apps, this can be accomplished with the Rack::Deflater middleware. For gzipped static assets, make sure that Rack::Deflater is loaded before ActionDispatch::Static in your middleware stack.

If I'm reading this correctly, my Python application code is now responsible for gzipping the responses? How would I go about compressing my static assets (e.g. css/js)? I'm using Flask and GUnicorn.

Maybe it doesn't feel right but surely they are telling you that. On python.org you have the documentation regarding gzip usage: docs.python.org/library/gzip.html — gforcada
just playing devils advocate here - why do you need to use gzip? You're not paying for bandwidth in/out of Heroku so why the need to compress? — John Beynon
I need to compress because my users will prefer to load up a page that weighs 300KB instead of 1MB! — Gabriel Florit

Tavis Rudd Tavis Rudd · Accepted Answer · 2011-10-21T16:35:19

You just need a wsgi middleware that gzips the response. See Gzipping all HTTP traffic with Pyramid or http://librelist.com/browser//flask/2010/6/14/gzip-compression/

How to enable gzip compression on Heroku Cedar (Python/Flask/Gunicorn)

2 Answers