don't allow a nil inbox to obliterate federation

CHANGELOG.md

@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## Unreleased
 
+## 2025.01.01
+
+Hotfix: Federation could break if a null value found its way into `should_federate?\1`
 
 ## 2025.01
 

lib/pleroma/web/activity_pub/publisher.ex

@@ -112,7 +112,7 @@ defp allowed_instances do
     Config.get([:mrf_simple, :accept])
   end
 
-  def should_federate?(url) do
+  def should_federate?(url) when is_binary(url) do
     %{host: host} = URI.parse(url)
 
     with {nil, false} <- {nil, is_nil(host)},
@@ -137,6 +137,8 @@ def should_federate?(url) do
     end
   end
 
+  def should_federate?(_), do: false
+
   @spec recipients(User.t(), Activity.t()) :: list(User.t()) | []
   defp recipients(actor, activity) do
     followers =

test/pleroma/web/activity_pub/publisher_test.exs

@@ -519,6 +519,9 @@ test "publish to url with with different ports" do
     test "should not obliterate itself if the inbox URL is bad" do
       url = "/inbox"
       refute Pleroma.Web.ActivityPub.Publisher.should_federate?(url)
+
+      url = nil
+      refute Pleroma.Web.ActivityPub.Publisher.should_federate?(url)
     end
   end
 end