Django and Heroku Cookbook

Collection of snippets and scripts that solve certain problems when deploying Django apps to Heroku.

Scripts in the bin directory are post-compile hooks that are invoked by the heroku-buildpack-python's compile step. You can install them by copying the bin directory into the root directory of your Heroku application repository.

Installing NodeJS and Less compiler for static assets compilation in your Django app

Heroku provides a bunch of different buildpacks that target many popular platforms like Python, Ruby, NodeJS and Java web apps and backends. While this is great and allows you to deploy virtually anything with a simple git command, the out-of-the-box solutions offer a limited set of utilities that are available during the Slug compilation phase. In particular no NodeJS, NPM or LESS Compiler is available in the heroku-buildpack-python. This means that there is no straightforward way of compiling .less stylesheets during the app deployment.

Fortunately, the Python buildpack provides hooks for running pre-compile and post-compile scripts. This can be used for customizing the compilation step and running additional commands without the necessity of maintaining a separate fork of Heroku's buildpack. The only thing you need to do is to create a proper bin/post_compile bash script in the root directory of your application.

The bin directory contains a set of scripts that can be used to install NodeJS/Less and invoke the manage.py compress command in your Django application:

• bin/post_compile
• bin/install_nodejs
• bin/install_less
• bin/run_compress

Just copy them over to your app reposiory and have your Less stylesheets compiled with an assets compressor like Django Compressor.

A note on hosting static files on Amazon S3. Remember to enable the environment variables if you are using django-storages and uploading static assets to S3:

heroku labs:enable user-env-compile

TBC