From 4ff52930936699161223b12c4396d5a5ad6736d4 Mon Sep 17 00:00:00 2001
From: Oneric <oneric@oneric.stub>
Date: Sun, 23 Jun 2024 20:46:58 +0200
Subject: [PATCH] Federate emoji as anonymous objects
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Usually an id should point to another AP object
and the image file isn’t an AP object. We currently
do not provide standalone AP objects for emoji and
don't keep track of remote emoji at all.
Thus just federate them as anonymous objects,
i.e. objects only existing within a parent context
and using an explicit null id.

IceShrimp.NET previously adopted anonymous objects
for remote emoji without any apparent issues. See:
https://iceshrimp.dev/iceshrimp/Iceshrimp.NET/commit/333611f65eb2a65b2779ece0435b5ba84bf60e99

Fixes: https://akkoma.dev/AkkomaGang/akkoma/issues/694
---
 CHANGELOG.md                                                    | 2 ++
 lib/pleroma/web/activity_pub/transmogrifier.ex                  | 2 +-
 .../web/activity_pub/transmogrifier/note_handling_test.exs      | 2 +-
 test/pleroma/web/activity_pub/views/user_view_test.exs          | 2 +-
 4 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3c743e5bd..c04ccec32 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## Fixed
 - Meilisearch: order of results returned from our REST API now actually matches how Meilisearch ranks results
+- Emoji are now federated as anonymous objects, fixing issues with
+  some strict servers e.g. rejecting e.g. remote emoji reactions
 
 ## Changed
 - Refactored Rich Media to cache the content in the database. Fetching operations that could block status rendering have been eliminated.
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index ca5e85f2e..75c1f0f0c 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -951,7 +951,7 @@ defp build_emoji_tag({name, url}) do
       "name" => ":" <> name <> ":",
       "type" => "Emoji",
       "updated" => "1970-01-01T00:00:00Z",
-      "id" => url
+      "id" => nil
     }
   end
 
diff --git a/test/pleroma/web/activity_pub/transmogrifier/note_handling_test.exs b/test/pleroma/web/activity_pub/transmogrifier/note_handling_test.exs
index 16ee31483..c8aa2a1ed 100644
--- a/test/pleroma/web/activity_pub/transmogrifier/note_handling_test.exs
+++ b/test/pleroma/web/activity_pub/transmogrifier/note_handling_test.exs
@@ -700,7 +700,7 @@ test "take_emoji_tags/1" do
     assert Transmogrifier.take_emoji_tags(user) == [
              %{
                "icon" => %{"type" => "Image", "url" => "https://example.org/firefox.png"},
-               "id" => "https://example.org/firefox.png",
+               "id" => nil,
                "name" => ":firefox:",
                "type" => "Emoji",
                "updated" => "1970-01-01T00:00:00Z"
diff --git a/test/pleroma/web/activity_pub/views/user_view_test.exs b/test/pleroma/web/activity_pub/views/user_view_test.exs
index abe91cdea..2a367b680 100644
--- a/test/pleroma/web/activity_pub/views/user_view_test.exs
+++ b/test/pleroma/web/activity_pub/views/user_view_test.exs
@@ -43,7 +43,7 @@ test "Renders with emoji tags" do
              "tag" => [
                %{
                  "icon" => %{"type" => "Image", "url" => "/test"},
-                 "id" => "/test",
+                 "id" => nil,
                  "name" => ":bib:",
                  "type" => "Emoji",
                  "updated" => "1970-01-01T00:00:00Z"