From 8552bd79b0faafcb653d9d2f50bb2f06d76eb663 Mon Sep 17 00:00:00 2001
From: Claire <claire.github-309c@sitedethib.com>
Date: Tue, 28 Jul 2026 10:30:21 +0200
Subject: [PATCH] Remove processing of collections of activities (#39932)

---
 ...service.rb => process_activity_service.rb} | 21 +++----------------
 app/workers/activitypub/processing_worker.rb  |  2 +-
 ...ec.rb => process_activity_service_spec.rb} |  2 +-
 .../activitypub/processing_worker_spec.rb     |  8 +++----
 4 files changed, 9 insertions(+), 24 deletions(-)
 rename app/services/activitypub/{process_collection_service.rb => process_activity_service.rb} (89%)
 rename spec/services/activitypub/{process_collection_service_spec.rb => process_activity_service_spec.rb} (99%)

diff --git a/app/services/activitypub/process_collection_service.rb b/app/services/activitypub/process_activity_service.rb
similarity index 89%
rename from app/services/activitypub/process_collection_service.rb
rename to app/services/activitypub/process_activity_service.rb
index 315e0c26354..2e66044ff20 100644
--- a/app/services/activitypub/process_collection_service.rb
+++ b/app/services/activitypub/process_activity_service.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-class ActivityPub::ProcessCollectionService < BaseService
+class ActivityPub::ProcessActivityService < BaseService
   include JsonLdHelper
   include DomainControlHelper
 
@@ -64,14 +64,8 @@ class ActivityPub::ProcessCollectionService < BaseService
       @json.delete('signature') unless safe_for_forwarding?(original_json, @json)
     end
 
-    case @json['type']
-    when 'Collection', 'CollectionPage'
-      process_items @json['items']
-    when 'OrderedCollection', 'OrderedCollectionPage'
-      process_items @json['orderedItems']
-    else
-      process_items [@json]
-    end
+    activity = ActivityPub::Activity.factory(@json, @account, **@options)
+    activity&.perform
   rescue JSON::ParserError
     nil
   end
@@ -90,15 +84,6 @@ class ActivityPub::ProcessCollectionService < BaseService
     %w(Delete Reject Undo Update).include?(@json['type'])
   end
 
-  def process_items(items)
-    items.reverse_each.filter_map { |item| process_item(item) }
-  end
-
-  def process_item(item)
-    activity = ActivityPub::Activity.factory(item, @account, **@options)
-    activity&.perform
-  end
-
   def actor_from_verified_ld_signature
     return unless @json['signature'].is_a?(Hash)
     return if domain_not_allowed?(@json['signature']['creator'])
diff --git a/app/workers/activitypub/processing_worker.rb b/app/workers/activitypub/processing_worker.rb
index 1bb94b7f264..5ccbaff44c3 100644
--- a/app/workers/activitypub/processing_worker.rb
+++ b/app/workers/activitypub/processing_worker.rb
@@ -13,7 +13,7 @@ class ActivityPub::ProcessingWorker
 
     return if actor.nil?
 
-    ActivityPub::ProcessCollectionService.new.call(body, actor, override_timestamps: true, delivered_to_account_id: delivered_to_account_id, delivery: true)
+    ActivityPub::ProcessActivityService.new.call(body, actor, override_timestamps: true, delivered_to_account_id: delivered_to_account_id, delivery: true)
   rescue ActiveRecord::RecordInvalid => e
     Rails.logger.debug { "Error processing incoming ActivityPub object: #{e}" }
   end
diff --git a/spec/services/activitypub/process_collection_service_spec.rb b/spec/services/activitypub/process_activity_service_spec.rb
similarity index 99%
rename from spec/services/activitypub/process_collection_service_spec.rb
rename to spec/services/activitypub/process_activity_service_spec.rb
index 7e3e5a66957..8e547c4f474 100644
--- a/spec/services/activitypub/process_collection_service_spec.rb
+++ b/spec/services/activitypub/process_activity_service_spec.rb
@@ -2,7 +2,7 @@
 
 require 'rails_helper'
 
-RSpec.describe ActivityPub::ProcessCollectionService do
+RSpec.describe ActivityPub::ProcessActivityService do
   subject { described_class.new }
 
   let(:actor) { Fabricate(:account, domain: 'example.com', uri: 'http://example.com/account') }
diff --git a/spec/workers/activitypub/processing_worker_spec.rb b/spec/workers/activitypub/processing_worker_spec.rb
index c06ba63d39b..dd99a5d52d5 100644
--- a/spec/workers/activitypub/processing_worker_spec.rb
+++ b/spec/workers/activitypub/processing_worker_spec.rb
@@ -8,11 +8,11 @@ RSpec.describe ActivityPub::ProcessingWorker do
   let(:account) { Fabricate(:account) }
 
   describe '#perform' do
-    it 'delegates to ActivityPub::ProcessCollectionService' do
-      allow(ActivityPub::ProcessCollectionService).to receive(:new)
-        .and_return(instance_double(ActivityPub::ProcessCollectionService, call: nil))
+    it 'delegates to ActivityPub::ProcessActivityService' do
+      allow(ActivityPub::ProcessActivityService).to receive(:new)
+        .and_return(instance_double(ActivityPub::ProcessActivityService, call: nil))
       subject.perform(account.id, '')
-      expect(ActivityPub::ProcessCollectionService).to have_received(:new)
+      expect(ActivityPub::ProcessActivityService).to have_received(:new)
     end
   end
 end