Revert "Fix rendering of template fields with start from trigger" #55037
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This reverts commit 4362c25 from apache#53071. The original change violated Airflow's architectural separation by making the Triggerer supervisor process load DAGs and attempt template rendering. This breaks with mapped operators that use lazy sequences requiring SUPERVISOR_COMMS, which only exists in task execution context. The Triggerer should operate purely on trigger database records and pre-computed trigger kwargs, not attempt runtime DAG operations. Fixes triggerer failures with mapped operators using XCom dependencies.
kaxil
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ashb,
bolkedebruin,
dstandish and
hussein-awala
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vatsrahul1001
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Aug 28, 2025
eladkal
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I wonder if there is easy way to add a test to prevent breaking this in the future
ashb
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hussein-awala
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mangal-vairalkar
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Aug 30, 2025
…ache#55037) This reverts commit 4362c25 from apache#53071. The original change violated Airflow's architectural separation by making the Triggerer supervisor process load DAGs and attempt template rendering. This breaks with mapped operators that use lazy sequences requiring SUPERVISOR_COMMS, which only exists in task execution context. The Triggerer should operate purely on trigger database records and pre-computed trigger kwargs, not attempt runtime DAG operations. Fixes triggerer failures with mapped operators using XCom dependencies.
nothingmin
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Sep 2, 2025
…ache#55037) This reverts commit 4362c25 from apache#53071. The original change violated Airflow's architectural separation by making the Triggerer supervisor process load DAGs and attempt template rendering. This breaks with mapped operators that use lazy sequences requiring SUPERVISOR_COMMS, which only exists in task execution context. The Triggerer should operate purely on trigger database records and pre-computed trigger kwargs, not attempt runtime DAG operations. Fixes triggerer failures with mapped operators using XCom dependencies.
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Fixes #55026
PR #53071 introduced a fundamental architectural issue by making the Triggerer supervisor process load DAGs and perform template rendering.
Error:
To Reproduce, run the following dag:
Issues Caused because of it:
ImportError: cannot import name 'SUPERVISOR_COMMS'StartTriggerArgsin Task SDK documentationRoot Cause:
The Triggerer supervisor process cannot access: XCom data (requires API calls). This can work in Trigger subprocess but not the supervisor process.
When mapped operators try to expand trigger args using lazy sequences, they fail because the architectural assumptions are violated.
^ Add meaningful description above
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