fix: allow deadline callbacks within the same dag module

[dondaum]

This enables the use of callables from the same Dag module for deadline alert callbacks. Airflow's Dag serialization adjusts the name of the Dag module during parsing to ensure its uniqueness. Consequently, once the callable is part of the same module, the module path can no longer be used.

Currently, this works only if you define the Callable in a separate module and subsequently import it into the Dag module—as described here.

How to reproduce

# sync_deadline_test.py
from datetime import datetime, timedelta
from airflow.sdk import SyncCallback, DAG, DeadlineAlert, DeadlineReference, task
from airflow.providers.standard.operators.empty import EmptyOperator


def run_sync_callback(text: str):
    print(text)


with DAG(
    dag_id="custom_callback_deadline_alert_sync",
    deadline=DeadlineAlert(
        reference=DeadlineReference.DAGRUN_QUEUED_AT,
        interval=timedelta(seconds=10),
        callback=SyncCallback(
            run_sync_callback,
            kwargs={
                "text": "🚨 Dag {{ dag_run.dag_id }} missed deadline at {{ deadline.deadline_time }}. DagRun: {{ dag_run }}"
            },
        ),
    ),
):

    c = EmptyOperator(task_id="example_task")

    @task()
    def wait():
        import time
        time.sleep(60)

    
    c >> wait()

Logs

2026-05-05 10:22:17.561532+00:00 [error    ] Callback execution failed      [callback_runner] callback_kwargs={'text': '🚨 Dag {{ dag_run.dag_id }} missed deadline at {{ deadline.deadline_time }}. DagRun: {{ dag_run }}', 'context': {'dag_run': {'dag_run_id': 'manual__2026-05-05T10:22:06.225020+00:00', 'dag_id': 'custom_callback_deadline_alert_sync', 'logical_date': '2026-05-05T10:22:06Z', 'queued_at': '2026-05-05T10:22:06.233422Z', 'start_date': '2026-05-05T10:22:06.267176Z', 'end_date': None, 'duration': None, 'data_interval_start': '2026-05-05T10:22:06Z', 'data_interval_end': '2026-05-05T10:22:06Z', 'run_after': '2026-05-05T10:22:06.225020Z', 'last_scheduling_decision': '2026-05-05T10:22:16.977390Z', 'run_type': 'manual', 'state': 'running', 'triggered_by': 'ui', 'triggering_user_name': 'admin', 'conf': {}, 'note': None, 'dag_versions': [{'id': '019df7a8-1f1a-771b-bdab-ed3e0499252d', 'version_number': 3, 'dag_id': 'custom_callback_deadline_alert_sync', 'bundle_name': 'dags-folder', 'bundle_version': None, 'created_at': '2026-05-05T10:21:23.610414Z', 'dag_display_name': 'custom_callback_deadline_alert_sync', 'bundle_url': None}], 'bundle_version': None, 'dag_display_name': 'custom_callback_deadline_alert_sync', 'partition_key': None}, 'deadline': {'id': '019df7a8-c5ac-787b-938b-4ab1a1b1d669', 'deadline_time': '2026-05-05T10:22:16.233422Z'}}} callback_path=unusual_prefix_895308c8175461ad72fc679b0fd85850413a13f3_sync_deadline_test.run_sync_callback error_detail=[{'exc_type': 'ModuleNotFoundError', 'exc_value': "No module named 'unusual_prefix_895308c8175461ad72fc679b0fd85850413a13f3_sync_deadline_test'", 'exc_notes': [], 'syntax_error': None, 'is_cause': False, 'frames': [{'filename': '/opt/airflow/task-sdk/src/airflow/sdk/execution_time/callback_supervisor.py', 'lineno': 111, 'name': 'execute_callback'}, {'filename': '/usr/python/lib/python3.10/importlib/__init__.py', 'lineno': 126, 'name': 'import_module'}, {'filename': '<frozen importlib._bootstrap>', 'lineno': 1050, 'name': '_gcd_import'}, {'filename': '<frozen importlib._bootstrap>', 'lineno': 1027, 'name': '_find_and_load'}, {'filename': '<frozen importlib._bootstrap>', 'lineno': 1004, 'name': '_find_and_load_unlocked'}], 'is_group': False, 'exceptions': []}] error_msg="Callback execution failed: ModuleNotFoundError: No module named 'unusual_prefix_895308c8175461ad72fc679b0fd85850413a13f3_sync_deadline_test'" loc=callback_supervisor.py:142
2026-05-05 10:22:17.562123+00:00 [error    ] Callback failed                [callback_runner] error="Callback execution failed: ModuleNotFoundError: No module named 'unusual_prefix_895308c8175461ad72fc679b0fd85850413a13f3_sync_deadline_test'" loc=callback_supervisor.py:218
2026-05-05T10:22:17.566313Z [info     ] Workload finished              [callback_supervisor] duration=0.06016514600014489 exit_code=1 loc=callback_supervisor.py:368 workload_id=019df7a8-c5ab-7541-9d7f-c0ba0018c132 workload_type=ExecutorCallback
2026-05-05T10:22:17.566601Z [error    ] Workload execution failed.     [airflow.executors.local_executor.LocalExecutor] loc=local_executor.py:110 workload_type=ExecuteCallback
Traceback (most recent call last):
  File "/opt/airflow/airflow-core/src/airflow/executors/local_executor.py", line 102, in _run_worker
    BaseExecutor.run_workload(
  File "/opt/airflow/airflow-core/src/airflow/executors/base_executor.py", line 670, in run_workload
    return supervise_callback(
  File "/opt/airflow/task-sdk/src/airflow/sdk/execution_time/callback_supervisor.py", line 376, in supervise_callback
    raise RuntimeError(f"Callback subprocess exited with code {exit_code}")
RuntimeError: Callback subprocess exited with code 1
2026-05-05T10:22:18.504254Z [info     ] Received executor event with state failed for callback 019df7a8-c5ab-7541-9d7f-c0ba0018c132 [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1271
2026-05-05T10:22:18.506357Z [error    ] Callback 019df7a8-c5ab-7541-9d7f-c0ba0018c132 failed: Execution failed [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1296
2026-05-05T10:22:18.512786Z [info     ] Getting all Callbacks          [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1118
2026-05-05T10:22:18.513512Z [info     ] executor                       [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1122
2026-05-05T10:22:18.513625Z [info     ] failed                         [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1123
2026-05-05T10:22:18.513704Z [info     ] 1                              [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1124
2026-05-05T10:22:18.513773Z [info     ] {'path': 'unusual_prefix_895308c8175461ad72fc679b0fd85850413a13f3_sync_deadline_test.run_sync_callback', 'dag_id': 'custom_callback_deadline_alert_sync', 'kwargs': {'text': '🚨 Dag {{ dag_run.dag_id }} missed deadline at {{ deadline.deadline_time }}. DagRun: {{ dag_run }}'}, 'prefix': 'deadline_alerts', 'executor': None} [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1125
2026-05-05T10:22:18.513858Z [info     ] Getting all Callbacks          [airflow.jobs.scheduler_job_runner.SchedulerJobRunner] loc=scheduler_job_runner.py:1126
2026-05-05T10:22:18.513924Z [info     ] No pending callb

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[ferruzzi]

Thanks for fixing this, it's a bit of tech debt I never did resolve. Left a couple comments.

[dondaum]

The failed CI is likely unrelated to this change. I will rebase as soon as the issue in the upstream CI is resolved.

[ferruzzi]

Yeah, test timed out, we can re-trigger just that one once the others finish

[dondaum]

Yeah, test timed out, we can re-trigger just that one once the others finish

should be good now.

[ferruzzi]

Approved with two small nits. Feel free to ignore them, they are pretty minor.

[potiuk]

@dondaum — There are 2 unresolved review thread(s) on this PR from ferruzzi, and you have engaged with each one (post-review commits and/or in-thread replies). Could you confirm whether you believe the feedback is fully addressed and the PR is ready for maintainer review confirmation?

If yes, please mark the thread(s) as resolved and ping the reviewer (ferruzzi) for a final look. They will either label the PR ready for maintainer review or follow up with additional feedback.

If you are still working on a thread, please reply with what is outstanding so the threads stay unresolved on purpose.

---

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

---

Drafted-by: Claude Code (Opus 4.7); reviewed by @potiuk before posting

[dondaum]

@dondaum — There are 2 unresolved review thread(s) on this PR from ferruzzi, and you have engaged with each one (post-review commits and/or in-thread replies). Could you confirm whether you believe the feedback is fully addressed and the PR is ready for maintainer review confirmation?

If yes, please mark the thread(s) as resolved and ping the reviewer (ferruzzi) for a final look. They will either label the PR ready for maintainer review or follow up with additional feedback.

If you are still working on a thread, please reply with what is outstanding so the threads stay unresolved on purpose.

Note: This comment was drafted by an AI-assisted triage tool and may contain mistakes. Once you have addressed the points above, an Apache Airflow maintainer — a real person — will take the next look at your PR. We use this two-stage triage process so that our maintainers' limited time is spent where it matters most: the conversation with you.

Drafted-by: Claude Code (Opus 4.7); reviewed by @potiuk before posting

@ferruzzi Just for info: I resolved both open PR comments based on this AI-assisted triage message.