Überauth Twitch

Twitch OAuth2 strategy for Überauth.

Installation

1. Setup your application in Twitch under your profile [applications menu][twitch-apps]

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

    def deps do
      [{:ueberauth_twitch, "~> 0.0.2"}]
    end

3. Add the strategy to your applications:

    def application do
      [applications: [:ueberauth_twitch]]
    end

4. Add Twitch to your Überauth configuration:

    config :ueberauth, Ueberauth,
      providers: [
        identity: { Ueberauth.Strategy.Identity, [
            callback_methods: ["POST"]
          ] },
        twitch: {Ueberauth.Strategy.Twitch, [default_scope: "user:read:email"]},
      ]

5. Update your provider configuration:

   config :ueberauth, Ueberauth.Strategy.Twitch.OAuth,
     client_id: System.get_env("TWITCH_CLIENT_ID"),
     client_secret: System.get_env("TWITCH_CLIENT_SECRET"),
     redirect_uri: System.get_env("TWITCH_REDIRECT_URI")

6. Include the Überauth plug in your controller:

   defmodule MyApp.AuthController do
     use MyApp.Web, :controller
     pipeline :browser do
       plug Ueberauth
       ...
      end
   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. You controller needs to implement callbacks to deal with Ueberauth.Auth and Ueberauth.Failure responses.

      def callback(%{assigns: %{ueberauth_failure: _fails}} = conn, _params) do
        Logger.debug(_fails)
        conn
        |> put_flash(:error, "Failed to authenticate.")
        |> redirect(to: "/")
      end
      def callback(%{assigns: %{ueberauth_auth: auth}} = conn, _params) do
        case UserFromAuth.find_or_create(auth) do
          {:ok, user} ->
            conn
            |> put_flash(:info, "Successfully authenticated.")
            |> put_session(:current_user, user)
            |> configure_session(renew: true)
            |> redirect(to: "/")
          {:error, reason} ->
            conn
            |> put_flash(:error, reason)
            |> redirect(to: "/")
        end
      end

For an example implementation see the [Überauth Example][example-app] application on how to integrate other strategies. Adding Twitch should be similar to Github.

Calling

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

/oauth2/authorize

Or with options:

/oauth2/authorize?scope=user:read:email

config :ueberauth, Ueberauth,
  providers: [
    identity: { Ueberauth.Strategy.Identity, [
        callback_methods: ["POST"]
      ] },
    twitch: {Ueberauth.Strategy.Twitch, [default_scope: "user:read:email"]},
  ]

It is also possible to disable the sending of the redirect_uri to Twitch. This is particularly useful when your production application sits behind a proxy that handles SSL connections. In this case, the redirect_uri sent by Ueberauth will start with http instead of https, and if you configured your Twitch OAuth application's callback URL to use HTTPS, Twitch will throw an uri_missmatch error. In addition if the redirect_uri on the the authorize request must match the redirect_uri on the token request.