Figaro Elixir

This project is based on figaro gem for Rails written by Steve Richert.

It's was created to manage ENV configuration for Elixir applications.

How does it work?

Figaro parses a git-ignored YAML file in your application and loads its values into environmental variables.

This is very handy for production environments when you don't want to store some of credentials in your repository.

Installation

Add Figaro Elixir as a dependency in your mix.exs file.

defp deps do
  [
    # ...
    {:figaro_elixir, "~> 1.0.0"}
  ]
end

You should also update your applications list to include Figaro:

def application do
  [
     applications: [
       # ...
       :figaro_elixir
     ]
  ]
end

Once you've done that, run mix deps.get in your command line to fetch the dependency.

Usage

The basic requirement is to have application.yml file in your project config directory.

Figaro will read it, parse it and use it to store environmental variables.

Please note that ENV is a simple key/value store with the following features:

• all values are converted to strings
• deeply nested configuration structures are not possible

Simple example

You can very easily start using Figaro for Elixir. Just create an appropriate file:

# config/application.yml

foo: bar
baz: qux

And run iex -S mix in your terminal. You will have an access to configuration values via FigaroElixir.env or System environmental variables:

iex(1)> FigaroElixir.env
%{"baz" => "qux", "foo" => "bar"}
iex(2)> FigaroElixir.env["baz"]
"qux"
iex(3)> System.get_env("foo")
nil
iex(4)> System.get_env("FOO")
"bar"

Keep in mind that system environmental variables keys are uppercased.

Environment-specific configuration

The power of Figaro elixir comes from distinguishing environments based on Mix.env property.

You may have a file defined like this:

a: a
b: ~

test:
  c: 1
  d: ~

And then after running MIX_ENV=test iex -S mix you will see:

iex(1)> FigaroElixir.env
%{"a" => "a", "b" => "~", "c" => "1", "d" => "~"}
iex(2)> FigaroElixir.env["c"]
"1"
iex(3)> System.get_env("C")
"1"

That's it. You don't have to do anything more.

Caveats

If you are using escript build tool, you need to have :mix among your apps in mix.exs file and copy application.yml file to your rel/project_name/config directory.

About the author

My name is Kamil Lelonek, I'm a full-stack developer and polyglot programmer. I love playing with different languages, technologies and tools. You can visit my website read my blog or follow me on twitter. In case of any problems or suggestions do not hesitate and create a pull request.