ruxxzebre / oauth_azure_activedirectory

Elixir Omniauth authentication for Azure Active Directory using JWT.

Oauth Azure Activedirectory

Omniauth client for Azure Active Directory using Microsoft identity hybrid authorization code flow

https://hex.pm/packages/oauth_azure_activedirectory

Installation

If available in Hex, the package can be installed by adding oauth_azure_activedirectory to your list of dependencies in mix.exs:

def deps do
  [
    {:oauth_azure_activedirectory, "~> 1.0.0"}
  ]
end

Configuration

config :oauth_azure_activedirectory, OauthAzureActivedirectory.Client,
  client_id: System.get_env("AZURE_CLIENT_ID"),
  client_secret: System.get_env("AZURE_CLIENT_SECRET"),
  tenant: System.get_env("AZURE_TENANT"),
  redirect_uri: "http://localhost:4000/auth/azureactivedirectory/callback",
  scope: "openid email profile",
  logout_redirect_url: "http://localhost:4000/users/logout"

Usage

# Add your routes, i.e.

scope "/auth", MyAppWeb do
  pipe_through :browser

  get "/:provider", AuthController, :authorize
  post "/:provider/callback", AuthController, :callback
end

# Adjust your controller actions for authorization and the callback

defmodule MyAppWeb.AuthController do
  use MyAppWeb, :controller

  alias MyApp.User
  alias OauthAzureActivedirectory.Client

  def authorize(conn, _params) do
    redirect conn, external: Client.authorize_url!
  end

  def callback(conn, _params) do
    {:ok, payload} = Client.callback_params(conn)
    email = payload["email"]
    case User.find_or_create(email) do
      {:ok, user} ->
        conn
        |> put_flash(:success, "Successfully authenticated.")
        |> put_session(:current_user, user)
        |> Guardian.Plug.sign_in(user) # if you are using Guardian
        |> redirect(to: "/")
      {:error, reason} ->
        conn
        |> put_flash(:error, reason)
        |> redirect(to: "/")
    end
  end
end

# Add a method to User model to process the data in JWT
def find_or_create(email) do
  query = from u in User, where: u.email == ^email
  case Repo.all(query) do
    [user] -> {:ok, user}
    [] -> create_user(%{email: email, password: SecureRandom.base64(16)})
  end
end

Information

Client.authorize_url!
# will generate a url similar to 
# https://login.microsoftonline.com/9b9eff0c-3e5t-1q2w-3e4r-fe98afcd0299/oauth2/authorize?client_id=984ebc2a-4ft5-8ea2-0000-59e43ccd614e&nonce=e22d15fa-853f-4d6a-9215-e2a206f48581&provider=azureactivedirectory&redirect_uri=http%3A%2F%2Flocalhost%3A4000%2Fauth%2Fazureactivedirectory%2Fcallback&response_mode=form_post&response_type=code+id_token

{:ok, payload} = Client.callback_params(conn)
# On a successful callback, jwt variable will return something like below.

%{
  exp: 1515604135,
  family_name: "Allen",
  given_name: "Otis",
  name: "Otis Allen",
  nonce: "e22d15fa-853f-4d6a-9215-e2a206f48581",
  email: "[e-mail]",
  uti: "heXGJdeefedrzEuc1bQNAA",
  ver: "2.0"
  ...
}

# For all attributes, see claims_supported in https://login.microsoftonline.com/common/.well-known/openid-configuration

Useful links

Azure AD token reference

Microsoft OpenID discovery document.

Trusted CA certificate for Azure Cloud Services