Add the auth pipeline for the Link API path.

lib/link_shortener_web/auth/pipeline.ex

@@ -0,0 +1,9 @@
+defmodule LinkShortenerWeb.Auth.Pipeline do
+  use Guardian.Plug.Pipeline, otp_app: :link_shortener,
+    module: LinkShortenerWeb.Auth.Guardian,
+    error_handler: LinkShortenerWeb.Auth.ErrorHandler
+
+  plug Guardian.Plug.VerifyHeader
+  plug Guardian.Plug.EnsureAuthenticated
+  plug Guardian.Plug.LoadResource
+end

lib/link_shortener_web/router.ex

@@ -17,6 +17,10 @@ defmodule LinkShortenerWeb.Router do
     plug :accepts, ["json"]
   end
 
+  pipeline :auth do
+    plug LinkShortenerWeb.Auth.Pipeline
+  end
+
   scope "/", LinkShortenerWeb do
     pipe_through :browser
 
@@ -29,12 +33,19 @@ defmodule LinkShortenerWeb.Router do
     pipe_through :api
 
     scope "/v1", Api.V1, as: :v1 do
-      resources "/links", LinkController
       post "/users/signup", UserController, :create
       post "/users/signin", UserController, :signin
     end
   end
 
+  scope "/api", LinkShortenerWeb do
+    pipe_through [:api, :auth]
+
+    scope "/v1", Api.V1, as: :v1 do
+      resources "/links", LinkController
+    end
+  end
+
   # Enables LiveDashboard only for development
   #
   # If you want to use the LiveDashboard in production, you should put