Heroku buildpack: Redis

This is a Heroku buildpack that allows an application to use an stunnel to connect securely to Heroku Redis. It is meant to be used in conjunction with other buildpacks as part of multi-buildpack.

Usage

In your application, you will need to make sure that you set your main buildpack as multi-buildpack:

$ heroku config:add BUILDPACK_URL=https://github.com/heroku/heroku-buildpack-multi.git

You'll then need to create a .buildpacks file at the root of your application directory. The redis-buildpack should be added along with the buildpack associated with the language that was used to build your application. In this example, the app was written in Ruby:

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

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

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/heroku/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

The buildpack will install and configure stunnel to connect to REDIS_URL over a SSL connection. Prepend bin/start-stunnel to any process in the Procfile to run stunnel alongside that process.

Multiple Redis Instances

If your application needs to connect to multiple Heroku Redis instances securely, you can set the STUNNEL_URLS config var to a list of config vars associated with the application:

$ heroku config:add STUNNEL_URLS="REDIS_URL HEROKU_REDIS_ROSE_URL"