Don't allow empty feed URLs

lib/frenzy_web/controllers/feed_controller.ex

@@ -36,8 +36,13 @@ defmodule FrenzyWeb.FeedController do
   end
 
   def create(conn, %{"feed" => %{"group_id" => group_id, "feed_url" => feed_url}}) do
+    user = conn.assigns[:user]
     group = Repo.get(Group, group_id)
+    feed_url = feed_url |> String.trim()
 
+    cond do
+      group != nil && group.user_id == user.id ->
+        if String.length(feed_url) > 0 do
           changeset =
             Ecto.build_assoc(group, :feeds, %{
               feed_url: feed_url,
@@ -49,7 +54,20 @@ defmodule FrenzyWeb.FeedController do
 
           {:ok, feed} = Repo.insert(changeset)
 
-    redirect(conn, to: Routes.group_path(Endpoint, :show, group_id))
+          conn
+          |> put_flash(:info, "Feed created")
+          |> redirect(to: Routes.group_path(Endpoint, :show, group_id))
+        else
+          conn
+          |> put_flash(:error, "Feed URL must not be empty")
+          |> redirect(to: Routes.group_path(Endpoint, :show, group_id))
+        end
+
+      true ->
+        conn
+        |> put_flash(:error, "Invalid group")
+        |> redirect(to: Routes.group_path(Endpoint, :index))
+    end
   end
 
   def edit(conn, _params) do