Skip to content
/ goth Public

Elixir package for Oauth authentication via Google Cloud APIs


Notifications You must be signed in to change notification settings


Repository files navigation



Google + Auth = Goth

A simple library to generate and retrieve OAuth2 tokens for use with Google Cloud Service accounts.


Note: below are instructions for using Goth v1.3+. For more information on earlier versions of Goth, see v1.2.0 documentation on

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

    def deps do
        {:goth, "~> 1.3"}
  2. Add Goth to your supervision tree:

    defmodule MyApp.Application do
      use Application
      def start(_type, _args) do
        credentials =
          |> System.fetch_env!()
          |> Jason.decode!()
        source = {:service_account, credentials}
        children = [
          {Goth, name: MyApp.Goth, source: source}
        Supervisor.start_link(children, strategy: :one_for_one)

    If you set GOOGLE_APPLICATION_CREDENTIALS or GOOGLE_APPLICATION_CREDENTIALS_JSON, have a ~/.config/gcloud/application_default_credentials.json file, ~/.config/gcloud/configurations/config_default file or deploy your application to Google Cloud, you can omit the :source option:

    def start(_type, _args) do
      children = [
        {Goth, name: MyApp.Goth}
      Supervisor.start_link(children, strategy: :one_for_one)

    If you want to use multiple credentials, you may consider doing:

    def start(_type, _args) do
      Supervisor.start_link(servers(), strategy: :one_for_one)
    defp servers do
      servers = [
        {MyApp.Cred1, source1},
        {MyApp.CredN, source2}
      for {name, source} <- servers do
        Supervisor.child_spec({Goth, name: name, source: source}, id: name)
  3. Fetch the token:

    iex> Goth.fetch!(MyApp.Goth)
      expires: 1453356568,
      token: "ya29.cALlJ4ICWRvMkYB-WsAR-CZnExE459PA7QPqKg5nei9y2T9-iqmbcgxq8XrTATNn_BPim",
      type: "Bearer",

See Goth.start_link/1 for more information about possible configuration options.

Upgrading from Goth 1.2

See Upgrading from Goth 1.2 guide for more information.

Community resources

Copyright and License

Copyright (c) 2016 Phil Burrows

This work is free. You can redistribute it and/or modify it under the terms of the MIT License. See the file for more details.