MSC4528: M_INCOMPATIBLE_SERVER error code - #4528
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M_INCOMPATIBLE_SERVER error codeM_INCOMPATIBLE_SERVER error code
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turt2live
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Implementation requirements:
- Server (throwing)
- Client (backwards compatibility)
- Client (forwards compatibility)
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Not sure if this really requires an impl?
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| Following [MSC4291](https://github.com/matrix-org/matrix-spec-proposals/pull/4291) and | ||
| [MSC4311](https://github.com/matrix-org/matrix-spec-proposals/pull/4311), the Server-Server API | ||
| tells sending servers to convert certain federation errors into 5xx errors over the Client-Server | ||
| API. [`PUT /_matrix/federation/v2/send_join/{roomId}/{eventId}`](https://spec.matrix.org/v1.19/server-server-api/#put_matrixfederationv2send_joinroomideventid) | ||
| and [`PUT /_matrix/federation/v2/invite/{roomId}/{eventId}`](https://spec.matrix.org/v1.19/server-server-api/#put_matrixfederationv2inviteroomideventid) | ||
| both say of their `400` response: | ||
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| > If `M_MISSING_PARAM` or `M_INVALID_PARAM` is returned and the request is associated | ||
| > with a Client-Server API request, the Client-Server API request SHOULD fail | ||
| > with a 5xx error rather than being passed through. |
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This MSC is spawning from trying to implement the spec, see element-hq/synapse#19723 (comment)
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Specify appropriate error codes for MSC4291 and MSC4311 where it was left as a 5xx.
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Disclaimer: Claude was used for the rough first draft. This has been subsequently edited a fair bit.