matrix-org / matrix-org/matrix-spec
What is the correct linearization for S2S `/backfill`?
Nobody has claimed this yet.
- Dominant language
- HTML
- Stars
- 330
- Forks
- 150
- Avg merge
- 2h 21m
- Merged PRs (30d)
- 3
Description
**Link to problem area**: https://spec.matrix.org/v1.6/server-server-api/#get_matrixfederationv1backfillroomid
**Issue**
It says:
> Starting from the PDU ID(s) given in the v argument, the PDUs given in v and the PDUs that preceded them are retrieved, up to the total number given by the limit.
... however, it does not specify *how* this is meant to order events, and specifically how it is meant to handle events with multiple `prev_events`. Is it a breadth-first search, like for `get_missing_events`? Is it in stream order? Something else?
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the linked Matrix S2S API section for GET /_matrix/federation/v1/backfill/{room_id}, then compare its wording with the get_missing_events behavior mentioned in the issue. Done means determining and documenting the ordering of returned PDUs, including how multiple prev_events are handled.
Written by the indexing model from the issue text.
Assessment
- Domain
- api
- Issue type
- Documentation
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100