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.