fix(moq-transport): compute correct object_id_delta in serve_subgroup#153
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thexeos wants to merge 1 commit intocloudflare:mainfrom
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fix(moq-transport): compute correct object_id_delta in serve_subgroup#153thexeos wants to merge 1 commit intocloudflare:mainfrom
object_id_delta in serve_subgroup#153thexeos wants to merge 1 commit intocloudflare:mainfrom
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The serve_subgroup method was hardcoding object_id_delta to 0 for every object re-served to downstream subscribers. Since object_id_delta is used to reconstruct the actual object ID, this caused all objects to appear as object_id=0 to downstream clients, corrupting the stream. Track the current object ID and compute the proper delta between consecutive objects so downstream subscribers receive correct IDs.
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In moq-transport/src/session/subscribed.rs, the
serve_subgroupmethod hardcodesobject_id_delta: 0for every object when re-serving subgroup data to downstream subscribers. Every object in a subgroup is received by downstream subscribers withobject_id=0.In draft-14, object IDs within a subgroup are delta-encoded (the receiver accumulates deltas to reconstruct absolute IDs -
current_object_id += delta). With delta always0, the accumulator never advances and this corrupts object ordering for any client subscribing through the relay, causing playback failures. Direct publisher-to-client connections are unaffected - only relayed subscriptions are broken.To fix, track a running
current_object_idaccumulator (starting at0) in the serving loop, then compute each delta asobject_id - current_object_id(matching the inverse of the decode logic in subscriber.rs:543).