Using envvault with Elixir

Note: Please ensure that you have completed the previous steps

Prerequisites

Erlang and Elixir installed
Mix (Elixir's build tool) installed
envvault CLI tool installed
An existing Elixir project

Usage

Running Your Application

To run your Elixir application with environment variables from envvault:

$ envvault run --env=dev mix run --no-halt

Caching Environment Variables

For better performance, you can cache your environment variables:

$ envvault run --env=dev -c -- mix run --no-halt

Example Implementation

Here is how to set up a basic Elixir web server with envvault:

# lib/my_app/application.ex
defmodule MyApp.Application do
  use Application

  def start(_type, _args) do
    # Your environment variables are automatically loaded
    port = System.get_env("PORT", "4000") |> String.to_integer()
    db_url = System.get_env("DB_URL")

    children = [
      {Plug.Cowboy, scheme: :http, plug: MyApp.Router, options: [port: port]}
    ]

    opts = [strategy: :one_for_one, name: MyApp.Supervisor]
    Supervisor.start_link(children, opts)
  end
end

# lib/my_app/router.ex
defmodule MyApp.Router do
  use Plug.Router

  plug :match
  plug :dispatch

  get "/" do
    send_resp(conn, 200, "Hello from envvault!")
  end

  match _ do
    send_resp(conn, 404, "Not Found")
  end
end

# mix.exs
defmodule MyApp.MixProject do
  use Mix.Project

  def project do
    [
      app: :my_app,
      version: "0.1.0",
      elixir: "~> 1.12",
      start_permanent: Mix.env() == :prod,
      deps: deps()
    ]
  end

  def application do
    [
      extra_applications: [:logger],
      mod: {MyApp.Application, []}
    ]
  end

  defp deps do
    [
      {:plug_cowboy, "~> 2.0"}
    ]
  end
end