Heroku buildpack: Redis

This is a Heroku buildpack that allows an application to use an stunnel to connect securely to Heroku Redis and other stunnel'ed services. It is meant to be used in conjunction with other buildpacks.

Usage

First you need to set this buildpack as your initial buildpack with:

$ heroku buildpacks:set https://github.com/PeriscopeData/heroku-buildpack-redis.git

Then you can add other buildpack(s) to compile your code like so:

$ heroku buildpacks:add https://github.com/heroku/heroku-buildpack-ruby.git

Choose the correct buildpack(s) for the language(s) used in your application.

For more information on using multiple buildpacks check out this devcenter article.

Next, for each process that should connect to Redis securely, you will need to preface the command in your Procfile with bin/start-stunnel. In this example, we want the web process to use a secure connection to Heroku Redis. The worker process doesn't interact with Redis, so bin/start-stunnel was not included:

$ cat Procfile
web:    bin/start-stunnel bundle exec unicorn -p $PORT -c ./config/unicorn.rb -E $RACK_ENV
worker: bundle exec rake worker

To wrap your console in stunnel, you should use bin/start-stunnel-interactive, which won't run your command in the background, so stdin/stout still work. $ cat Procfile console: bin/start-stunnel-interactive bundle exec rails console

We're then ready to deploy to Heroku with an encrypted connection between the dynos and Heroku Redis:

$ git push heroku master
...
-----> Fetching custom git buildpack... done
-----> Multipack app detected
=====> Downloading Buildpack: https://github.com/PeriscopeData/heroku-buildpack-redis.git
=====> Detected Framework: stunnel
       Using stunnel version: 5.02
       Using stack version: cedar
-----> Fetching and vendoring stunnel into slug
-----> Moving the configuration generation script into app/bin
-----> Moving the start-stunnel script into app/bin
-----> stunnel done
=====> Downloading Buildpack: https://github.com/heroku/heroku-buildpack-ruby.git
=====> Detected Framework: Ruby/Rack
-----> Using Ruby version: ruby-2.2.2
-----> Installing dependencies using Bundler version 1.7.12
...

Configuration

Add any URLs you want to be tunneled to the STUNNEL_URLS env var. To tunnel just redis, set STUNNEL_URLS=REDIS_URL Prepend bin/start-stunnel to any process in the Procfile to run stunnel alongside that process.

Stunnel settings

Some settings are configurable through app config vars at runtime:

• STUNNEL_ENABLED: Default to true, enable or disable stunnel.