Add the API to update the Link model.

lib/link_shortener_web/controllers/api/v1/link_controller.ex

@@ -24,6 +24,13 @@ defmodule LinkShortenerWeb.Api.V1.LinkController do
     link = Links.get_one(id)
     render(conn, "show.json", link: link)
   end
+
+  def update(conn, %{"id" => id, "link" => link_params}) do
+    link = Links.get_one(id)
+
+    with {:ok, %Link{} = link} <- Links.update_one(link, link_params) do
+      render(conn, "show.json", link: link)
+    end
   end
 
   def delete(conn, %{"id" => id}) do