From 93e8a15415c35dbe4089b5d20c08161646ba76b3 Mon Sep 17 00:00:00 2001
From: Eugen Rochko <eugen@zeonfederated.com>
Date: Sat, 8 Jul 2023 20:00:02 +0200
Subject: [PATCH] Add forwarding of reported replies to servers being replied
 to (#25341)

---
 app/lib/activitypub/activity/flag.rb |  9 +++---
 app/services/report_service.rb       | 14 +++++----
 spec/services/report_service_spec.rb | 43 +++++++++++++++++++++-------
 3 files changed, 46 insertions(+), 20 deletions(-)

diff --git a/app/lib/activitypub/activity/flag.rb b/app/lib/activitypub/activity/flag.rb
index dc1932f597..304cf0ad2f 100644
--- a/app/lib/activitypub/activity/flag.rb
+++ b/app/lib/activitypub/activity/flag.rb
@@ -4,13 +4,14 @@ class ActivityPub::Activity::Flag < ActivityPub::Activity
   def perform
     return if skip_reports?
 
-    target_accounts            = object_uris.filter_map { |uri| account_from_uri(uri) }.select(&:local?)
-    target_statuses_by_account = object_uris.filter_map { |uri| status_from_uri(uri) }.select(&:local?).group_by(&:account_id)
+    target_accounts            = object_uris.filter_map { |uri| account_from_uri(uri) }
+    target_statuses_by_account = object_uris.filter_map { |uri| status_from_uri(uri) }.group_by(&:account_id)
 
     target_accounts.each do |target_account|
-      target_statuses = target_statuses_by_account[target_account.id]
+      target_statuses     = target_statuses_by_account[target_account.id]
+      replied_to_accounts = Account.local.where(id: target_statuses.filter_map(&:in_reply_to_account_id))
 
-      next if target_account.suspended?
+      next if target_account.suspended? || (!target_account.local? && replied_to_accounts.none?)
 
       ReportService.new.call(
         @account,
diff --git a/app/services/report_service.rb b/app/services/report_service.rb
index 0ce525b071..3444e1dfaf 100644
--- a/app/services/report_service.rb
+++ b/app/services/report_service.rb
@@ -45,11 +45,15 @@ class ReportService < BaseService
   end
 
   def forward_to_origin!
-    ActivityPub::DeliveryWorker.perform_async(
-      payload,
-      some_local_account.id,
-      @target_account.inbox_url
-    )
+    # Send report to the server where the account originates from
+    ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, @target_account.inbox_url)
+
+    # Send report to servers to which the account was replying to, so they also have a chance to act
+    inbox_urls = Account.remote.where(id: Status.where(id: reported_status_ids).where.not(in_reply_to_account_id: nil).select(:in_reply_to_account_id)).inboxes - [@target_account.inbox_url]
+
+    inbox_urls.each do |inbox_url|
+      ActivityPub::DeliveryWorker.perform_async(payload, some_local_account.id, inbox_url)
+    end
   end
 
   def forward?
diff --git a/spec/services/report_service_spec.rb b/spec/services/report_service_spec.rb
index b8ceedb851..660ce3db23 100644
--- a/spec/services/report_service_spec.rb
+++ b/spec/services/report_service_spec.rb
@@ -17,24 +17,45 @@ RSpec.describe ReportService, type: :service do
 
   context 'with a remote account' do
     let(:remote_account) { Fabricate(:account, domain: 'example.com', protocol: :activitypub, inbox_url: 'http://example.com/inbox') }
+    let(:forward) { false }
 
     before do
       stub_request(:post, 'http://example.com/inbox').to_return(status: 200)
     end
 
-    it 'sends ActivityPub payload when forward is true' do
-      subject.call(source_account, remote_account, forward: true)
-      expect(a_request(:post, 'http://example.com/inbox')).to have_been_made
+    context 'when forward is true' do
+      let(:forward) { true }
+
+      it 'sends ActivityPub payload when forward is true' do
+        subject.call(source_account, remote_account, forward: forward)
+        expect(a_request(:post, 'http://example.com/inbox')).to have_been_made
+      end
+
+      it 'has an uri' do
+        report = subject.call(source_account, remote_account, forward: forward)
+        expect(report.uri).to_not be_nil
+      end
+
+      context 'when reporting a reply' do
+        let(:remote_thread_account) { Fabricate(:account, domain: 'foo.com', protocol: :activitypub, inbox_url: 'http://foo.com/inbox') }
+        let(:reported_status) { Fabricate(:status, account: remote_account, thread: Fabricate(:status, account: remote_thread_account)) }
+
+        before do
+          stub_request(:post, 'http://foo.com/inbox').to_return(status: 200)
+        end
+
+        it 'sends ActivityPub payload to the author of the replied-to post' do
+          subject.call(source_account, remote_account, status_ids: [reported_status.id], forward: forward)
+          expect(a_request(:post, 'http://foo.com/inbox')).to have_been_made
+        end
+      end
     end
 
-    it 'does not send anything when forward is false' do
-      subject.call(source_account, remote_account, forward: false)
-      expect(a_request(:post, 'http://example.com/inbox')).to_not have_been_made
-    end
-
-    it 'has an uri' do
-      report = subject.call(source_account, remote_account, forward: true)
-      expect(report.uri).to_not be_nil
+    context 'when forward is false' do
+      it 'does not send anything' do
+        subject.call(source_account, remote_account, forward: forward)
+        expect(a_request(:post, 'http://example.com/inbox')).to_not have_been_made
+      end
     end
   end