From c51a2240d10a22296a92414b53a1373c328c6298 Mon Sep 17 00:00:00 2001 From: kegsay <7190048+kegsay@users.noreply.github.com> Date: Tue, 20 Feb 2024 14:12:06 +0000 Subject: [PATCH] bugfix: always prefer unthreaded receipt when >1 exist (MSC4102) (#16927) Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com> --- changelog.d/16927.bugfix | 1 + synapse/storage/databases/main/receipts.py | 21 ++++++++++++++++++--- 2 files changed, 19 insertions(+), 3 deletions(-) create mode 100644 changelog.d/16927.bugfix diff --git a/changelog.d/16927.bugfix b/changelog.d/16927.bugfix new file mode 100644 index 0000000000..ecc62a148c --- /dev/null +++ b/changelog.d/16927.bugfix @@ -0,0 +1 @@ +Always prefer unthreaded receipt when >1 exist ([MSC4102](https://github.com/matrix-org/matrix-spec-proposals/pull/4102)). \ No newline at end of file diff --git a/synapse/storage/databases/main/receipts.py b/synapse/storage/databases/main/receipts.py index 3c7708f5f3..8a426d2875 100644 --- a/synapse/storage/databases/main/receipts.py +++ b/synapse/storage/databases/main/receipts.py @@ -472,9 +472,24 @@ class ReceiptsWorkerStore(SQLBaseStore): event_entry = room_event["content"].setdefault(event_id, {}) receipt_type_dict = event_entry.setdefault(receipt_type, {}) - receipt_type_dict[user_id] = db_to_json(data) - if thread_id: - receipt_type_dict[user_id]["thread_id"] = thread_id + # MSC4102: always replace threaded receipts with unthreaded ones if there is a clash. + # Specifically: + # - if there is no existing receipt, great, set the data. + # - if there is an existing receipt, is it threaded (thread_id present)? + # YES: replace if this receipt has no thread id. NO: do not replace. + # This means we will drop some receipts, but MSC4102 is designed to drop semantically + # meaningless receipts, so this is okay. Previously, we would drop meaningful data! + receipt_data = db_to_json(data) + if user_id in receipt_type_dict: # existing receipt + # is the existing receipt threaded and we are currently processing an unthreaded one? + if "thread_id" in receipt_type_dict[user_id] and not thread_id: + receipt_type_dict[ + user_id + ] = receipt_data # replace with unthreaded one + else: # receipt does not exist, just set it + receipt_type_dict[user_id] = receipt_data + if thread_id: + receipt_type_dict[user_id]["thread_id"] = thread_id results = { room_id: [results[room_id]] if room_id in results else []