fix-heartbeat-after-completion - Branch - PrefectHQ/prefect

fix: prevent heartbeat events after flow run completes

#19641

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fix-heartbeat-after-completion

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bench_import_prefect_flow

benches/bench_import.py

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bench_task_decorator

benches/bench_tasks.py

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benches/bench_import.py

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f702f1e

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fix: prevent heartbeat events after flow run completes Fixes a race condition where heartbeat events could be emitted after a flow run has already completed. This could incorrectly trigger zombie flow detection automations. The issue occurred because the periodic heartbeat loop iterates over _flow_run_process_map and collects flow runs to emit heartbeats for. Between iteration and actual emission (which involves async lookups), a flow run could complete and be removed from the map. The heartbeat would still be emitted, appearing after the terminal state event. The fix adds a check_incomplete parameter to _emit_flow_run_heartbeat. When True (used by the periodic heartbeat loop), it verifies the flow run is still in the process map before emitting. This prevents emitting heartbeats for flow runs that completed during heartbeat preparation. Closes #19598 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>

5c3f1f1

13 hours ago

by zzstoatzz

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