Renv

The name stands for "Remote ENVironment" (thanks, captain obvious).

renv manages your .env (envrionment variables) files so they are never stored on your local machine.

It can be used to provide a replacement to Heroku's superb config:get / config:set in Capistrano-land.

Installation

You know the dance:

$ gem install renv

You may need in your application's Gemfile, of course.

Configuration

You will need to set at least two variables in your environment:

RENV_AWS_KEY_myapp=...
RENV_AWS_SECRET_myapp=...

Plus a few optional ones (can be overriden on the command-line):

RENV_APP=myapp
RENV_BUCKET_myapp=...

Usage

Commands:
  renv del KEY...        # deletes KEY and its value
  renv dump              # dumps all key-value pairs in .env format
  renv get KEY           # returns the value of KEY
  renv help [COMMAND]    # Describe available commands or one specific command
  renv load              # set keys from standard input in .env format
  renv set KEY=VALUE...  # sets the value of KEY to VALUE

Options:
  -a, [--app=APP]        # Application name, defaults to RENV_APP
  -b, [--bucket=BUCKET]  # S3 bucket storing environment(s), defaults to RENV_BUCKET_<app>
  -n, [--name=NAME]      # Environment name, e.g. for staging apps, defaults to app name

How it works

Simply enough:

• get and dump will read a .env-formatted file from S3 (and parse it, in the case of get)
• set, load, and del will write them back.

Every time a write to S3 occurs, two files get written: one named latest (all read operations look at this file), and one named with the current ISO timestamp (for backup purposes... in case you delete a needed key!)

Caveat: No effort is made to be safeguard against multiple users writing at the same time.

Hooking to Capistrano

Here's an example, assuming you use the multistage extensions:

after 'deploy:finalize_update' do
  environment = %x(bundle exec renv dump -a my_app -b my_bucket -n #{stage})
  unless $?.success?
    warn "Failed to obtain environment variables"
    exit 1
  end
  put environment, "#{release_path}/.env"
end

The environment variables will briefly live in Capistrano's memory, but will not be saved to your disk.

Contributing

Yes, please!

1. Fork it ( https://github.com/HouseTrip/renv/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request