Sensor task is not skipped after ShortCircuitOperator task if direct child relation

[Ferdinanddb]

Apache Airflow Provider(s)

standard

Versions of Apache Airflow Providers

1.3.0

Apache Airflow version

3.0.2

Operating System

Debian GNU/Linux 12 (bookworm)

Deployment

Official Apache Airflow Helm Chart

Deployment details

I created my own custom container image using the official one docker.io/apache/airflow:3.0.2-python3.12

In it I install the the following requirements.txt file with the following command:

RUN pip install \
    --no-cache-dir \
    -r /var/airflow/requirements.txt

apache-airflow[async]==3.0.2
astronomer-cosmos==1.10.1
apache-airflow-providers-amazon==9.9.0
apache-airflow-providers-google==16.0.0
apache-airflow-providers-cncf-kubernetes==10.6.0
apache-airflow-providers-celery==3.12.0
apache-airflow-providers-standard==1.3.0
apache-airflow-providers-postgres==6.2.0
apache-airflow-providers-slack==9.1.1
apache-airflow-providers-http==5.3.1
apache-airflow-providers-fab==2.2.1

I did not use the pip's constraint flag to be able to try using the latest providers' versions.

What happened

I am using the ShortCircuitOperator and it turns out that my sensor task (custom sensor class created by me to add a missing option on the official S3FileSensor) that is happening after my ShortCircuitOperator is not skipped when my task evaluates to False (meaning all child tasks should be skipped).

In the following screenshot showing the XCOMs, we can clearly see that the sensor task is not included in the value.

The code of the two first tasks is:

    check_dis_is_mon_to_fri_not_holiday = ShortCircuitOperator(
        task_id="check_dis_is_mon_to_fri_not_holiday",
        python_callable=should_run_mon_to_fri,
        op_kwargs={
            "check_algoseek_holiday": True,
        },
    )

    wait_for_ticker_to_secid_lookup_s3_file = S3FileSensor(
        task_id="wait_for_ticker_to_secid_lookup_s3_file",
        bucket_name=S3_EQUITY_LOOKUP_BUCKET_NAME,
        object_key="ticker_to_secid_lookup.csv",
        poke_interval=600,
        timeout=timedelta(seconds=24 * 60 * 60 * 5),
        modified_after="{{ data_interval_end | ts }}",
        mode="poke",
        deferrable=True,
    )

The interesting part is that if I add a dummy EmptyOperator task between my shortcircuit and my sensor then I get the expected behavior, this workaround is fine for me but I still think something is off.

What you think should happen instead

The ShortCircuitOperator should skip all the child tasks (Operators, Sensors, ...) when it evaluates to False and when the ignore_downstream_trigger_rules flag is set to True.

How to reproduce

I think it can be reproduced by trying to execute any Sensor task after a ShortCircuitOperator task evaluates to False.

Anything else

My workaround is to add a dummy EmptyOperator between the ShortCircuitOperator and the Sensor, it works as expected with that, but it also clearly indicates that something is off in my opinion. The same code was working fine in Airflow 2.11.0.

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[dominikhei]

I was able to replicate it with both a deferable and non deferrable S3KeySensor. Your workaround also works for me. trigger_rule none_skipped doesn't stop it either.