Mellon

An authentication module for Plug applications.

Intallation

defp deps do
  [{:mellon, "~> 0.1.1"}]
end

How to use

See /examples for a working example.

defmodule MyApp do
  import Plug.Conn
  use Plug.Builder

  plug Mellon, validator: {MyApp, :validate, []}, header: "X-AUTH"

  plug :index

  def validate({conn, token}) do
    case token do
      "ValidToken" -> {:ok, {"userdata"}, conn}
      _ -> {:error, [], conn}
  end

  def index(conn, _opts) do
    send_resp(conn, 200, "Secure area")
  end
end

To authenticated for this example using curl you might do the following:

curl --header "X-AUTH: Token: ValidToken" localhost:4000/hello

Configuration

You can configure some parameters while initializing Mellon.

Required

validator: The function that validates the token. Must return {:ok, userdata, conn} if valid and {:error, conn} if not.

Optional

header: The http header used for tokens. Will default to 'Authorization'.

block: Boolean representing if we should return a 401 and stop the chain, if the user is unauthenticated. set block: false, and you can handle displaying a message, oredirecting from the controller.

Return object from validator

The validator can return some options.

All requests that are authenticated should return

{:ok, cargo, conn}

cargo can be any object that you would like to pass along. it will be assigned to the request so you can access it later in your controller. It will be assigned to :credentials. To access it later you could do the following: conn.assigns[:credentials].

If authentication fails you should return {:error, options, conn}.

Where options is a Keyword containing status: and message. Both are optional.

In case you want a custom Unauthenticated message include [message: 'Get out of here!']