Überauth Google

Google OAuth2 strategy for Überauth.

Installation

  1. Setup your application at Google Developer Console.

  2. Add :ueberauth_google to your list of dependencies in mix.exs:

     def deps do
       [{:ueberauth_google, "~> 0.8"}]
     end
  3. Add the strategy to your applications:

     def application do
       [applications: [:ueberauth_google]]
     end
  4. Add Google to your Überauth configuration:

     config :ueberauth, Ueberauth,
       providers: [
         google: {Ueberauth.Strategy.Google, []}
       ]
  5. Update your provider configuration:

    Use that if you want to read client ID/secret from the environment variables in the compile time:

    config :ueberauth, Ueberauth.Strategy.Google.OAuth,
      client_id: System.get_env("GOOGLE_CLIENT_ID"),
      client_secret: System.get_env("GOOGLE_CLIENT_SECRET")

    Use that if you want to read client ID/secret from the environment variables in the run time:

    config :ueberauth, Ueberauth.Strategy.Google.OAuth,
      client_id: {System, :get_env, ["GOOGLE_CLIENT_ID"]},
      client_secret: {System, :get_env, ["GOOGLE_CLIENT_SECRET"]}
  6. Include the Überauth plug in your controller:

    defmodule MyApp.AuthController do
      use MyApp.Web, :controller
      plug Ueberauth
      ...
    end
  7. Create the request and callback routes if you haven't already:

    scope "/auth", MyApp do
      pipe_through :browser
    
      get "/:provider", AuthController, :request
      get "/:provider/callback", AuthController, :callback
    end
  8. Your controller needs to implement callbacks to deal with Ueberauth.Auth and Ueberauth.Failure responses.

For an example implementation see the Überauth Example application.

Calling

Depending on the configured url you can initiate the request through:

/auth/google

Or with options:

/auth/google?scope=email%20profile

By default the requested scope is "email". Scope can be configured either explicitly as a scope query value on the request path or in your configuration:

config :ueberauth, Ueberauth,
  providers: [
    google: {Ueberauth.Strategy.Google, [default_scope: "email profile plus.me"]}
  ]

You can also pass options such as the hd parameter to limit sign-in to a particular Google Apps hosted domain, or prompt and access_type options to request refresh_tokens and offline access.

config :ueberauth, Ueberauth,
  providers: [
    google: {Ueberauth.Strategy.Google, [hd: "example.com", prompt: "select_account", access_type: "offline"]}
  ]

To guard against client-side request modification, it's important to still check the domain in info.urls[:website] within the Ueberauth.Auth struct if you want to limit sign-in to a specific domain.

License

Please see LICENSE for licensing details.