# EnvHelper

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Using system variables is good practice, and env helper helps you practice it. [Documentation available online](https://hexdocs.pm/env_helper/api-reference.html)

## Installation

The package can be installed from hex.pm:

  1. Add env_helper to your list of dependencies in `mix.exs`:

        def deps do
          [{:env_helper, "~> 0.0.1"}]
        end

## Usage

#### General

Create a module and import `EnvHelper`, then use the `system_env` and `app_env` macros to to define functions for that module.

#### system_env

    defmodule Settings
      import EnvHelper
      system_env(:base_url, "localhost:9000")
    end

This maps the method `Settings.base_url` to the system environment variable `BASE_URL`, or to the default value if the environment variable is not set.

Some settings might need to be integer values in your code, but will be strings when read from the environment helper. In such cases you can use the :string_to_integer flag:

    system_env(:port, 9876, :string_to_integer)

Which will ensure that `PORT` environment variable will be interpreted as an integer.

#### app_env

In config/test.exs:

    config :my_app, :port, 5678

In settings.ex:

    defmodule Settings do
      import EnvHelper
      app_env(:port, [:my_app, :port], 1234)
    end

Assuming that the `config/dev.exs` file does not define a   `:my_app, :port` variable, in the test environment `Settings.port` is `5678` and in dev it will be `1234`.