From 5b7a0dba6d2c019f7bee5727dee04f0f8bf8cb27 Mon Sep 17 00:00:00 2001
From: Shadowfacts <me@shadowfacts.net>
Date: Wed, 25 Aug 2021 23:15:30 -0400
Subject: [PATCH] Fix error in outbox when no activities exist

---
 lib/clacks_web/controllers/outbox_controller.ex | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/lib/clacks_web/controllers/outbox_controller.ex b/lib/clacks_web/controllers/outbox_controller.ex
index 3b4ba2f..5ee7d83 100644
--- a/lib/clacks_web/controllers/outbox_controller.ex
+++ b/lib/clacks_web/controllers/outbox_controller.ex
@@ -50,13 +50,22 @@ defmodule ClacksWeb.OutboxController do
   end
 
   defp outbox_page(conn, pagination_params, activities) do
-    last_id = List.last(activities).id
+    next =
+      case activities do
+        [] ->
+          # todo: is nil the right thing here?
+          nil
+
+        _ ->
+          last_id = List.last(activities).id
+          current_url(conn, %{max_id: last_id})
+      end
 
     %{
       "type" => "OrderedColletionPage",
       "partOf" => current_url(conn, %{}),
       "id" => current_url(conn, pagination_params),
-      "next" => current_url(conn, %{max_id: last_id}),
+      "next" => next,
       "orderedItems" => Enum.map(activities, & &1.data)
     }
   end