Note that MSC1831 changes the order, so the changes to MSC1708 might not make sense when combining all the proposals together. However, independently the change should make sense.
Original proposal: https://github.com/matrix-org/matrix-doc/pull/1659
Implementation proofs (some traversing of the PR tree may be required to get all of them):
* https://github.com/matrix-org/synapse/pull/4483
* https://github.com/matrix-org/synapse/pull/4499
This doesn't intentionally change anything from the proposal.
**Implementation details**:
The simple part of this is the introduction of a rooms/v3.html document. The somewhat unclear part is the stuff done to the s2s definitions. This pulls `unsigned_pdu` out to `unsigned_pdu_base` (all fields except `event_id`) where it can be reused in `pdu` and `pdu_v3` (for rooms v3). These definitions are further moved into the room version specifications where they can highlight the exact schemas in detail.
Version 1 has been updated to include the pre-existing event format, however the core principles of the room have not been changed. The same applies to room version 2. Room versions have immutable core principles once in the spec, otherwise these format changes would land in a pre-existing version.
The client-server API event formats will need updating, however that is being punted to a different commit to try and keep these changes reviewable.
The "Room Specification" (or "Room Version Specification") is the specification that defines which room versions do what and are intended to be documents which speak the truth about how rooms operate under the hood.
The approach taken here is a bit different than other specifications. For starters, the specification is versioned in this project instead of relying on the matrix.org repository to track compiled HTML. This is done for a couple reasons, the first being we're still developing the v1 specification while concurrently making a v2 spec and the second being trying to reduce the reliance on matrix.org's repository for specifications.
Because the room spec is built into versions, some changes needed to be made. The `targets.yaml` now has a special syntax for indicating what version something is at, and the changelog generator can handle rendering different versions of the same changelog (as parsed from the RST). Some additional work has been put in to the changelog parsing to allow us to reference the v1 room spec as "v1" without having to sacrifice clarity in the changelog headings.
Finally, this moves the state resolution algorithms into the versioned
spec as a result of MSC1759 (https://github.com/matrix-org/matrix-doc/pull/1759).
Note: this does not introduce the concept of versioned schemas (tabs) that I was previously working with. There's currently no use for them, so they are shelved elsewhere.