߲jddZddlmZddlZddlmZej eZddZ d dZ d dZ y) aBest-effort accessors for the single-writer stream fence. The fence lives on ``AIAgent`` (``_claim_stream_writer`` / ``_stream_writer_is_current``) but is used from other streaming modules. Calling it directly would turn an *additive* safety net into a fatal AttributeError on a partially-updated checkout, hot-reloaded gateway, duck-typed agent, or test double (a cron job died this way). The fence may only drop a *provably* superseded stream, never the sole writer, so when it is unavailable or raises the degradation is "no fence". ) annotationsN)Anyc(t|dtddS)zvClaim the delta sink for this stream attempt; ``0`` (never fenced) when the agent lacks the fence or the claim raised._claim_stream_writerrz!claim failed; proceeding unfenced) _fence_callint)agents ?/home/ubuntu/.hermes/hermes-agent/agent/stream_single_writer.pyclaim_stream_writerr s u4c1>a bbc0|syt|dtdd|S)zwTrue when ``token`` is still the active writer; a falsy token or a fence-less agent cannot prove supersession, so True.T_stream_writer_is_currentz,is_current check failed; treating as current)rbool)r tokens r stream_writer_is_currentrs  u94Guw| }}r ct||d}t|r |||S|S#t$rtj d|dY|SwxYw)zdCall ``agent.(*args)`` when it exists; ``fallback`` when missing or raising (logged at debug).Nzstream single-writer: %sT)exc_info)getattrcallable Exceptionloggerdebug)r namecastfallback failure_noteargsfns r rrs] d #B| RD ? " O R LL3\DL Q O Rs '!A  A )r rreturnr)r rrrrr)r rrstrrr ) __doc__ __future__rloggingtypingr getLogger__name__rr rrr r r(s8#   8 $c ~r