Add allowed_run_types to whitelist specific dag run types

[guan404ming]

Related Issue

Closes #61710

Why

Allow dag authors to restrict which run types (manual, scheduled, backfill, asset-triggered) are permitted on a per-DAG basis.

How

• Add allowed_run_types field to definition, DagModel, serialization, and a DB migration
• Enforce the allow list in scheduler, trigger, backfill, and asset materialization API routes
• Disable the trigger button in the UI when manual runs are not allowed

---

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  Claude Code with Opus 4.6

---

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[eladkal]

Great work!
I'm having an issue with trying to run:

dag = DAG(
    ...
    schedule="@daily",
    deny_dag_run_types=DagRunType.MANUAL
)

I get

Traceback (most recent call last):
  File "/usr/python/lib/python3.11/enum.py", line 714, in __call__
    return cls.__new__(cls, value)
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/python/lib/python3.11/enum.py", line 1137, in __new__
    raise ve_exc
ValueError: 'm' is not a valid DagRunType

It's solved if I change deny_dag_run_types=[DagRunType.MANUAL].
I think we should allow also a single value... It makes things easier and shouldn't be too hard to fix

[eladkal]

I think we are missing tests for cases like:

from airflow.utils.types import DagRunType
my_dag = DAG(
    ...,
    schedule=[example_asset]
    deny_dag_run_types = [DagRunType.ASSET_TRIGGERED]
)

from airflow.utils.types import DagRunType
my_dag = DAG(
    ...,
    schedule="@daily"
    deny_dag_run_types = [DagRunType.SCHEDULED]
)

from airflow.utils.types import DagRunType
my_dag = DAG(
    ...,
    schedule=None
    deny_dag_run_types = [DagRunType.MANUAL]
)

Test should verify broken dag message is raised for all these 3 cases

[guan404ming]

Test should verify broken dag message is raised for all these 3 cases

Thanks, just updated to make the tests covering more cased.

It's solved if I change deny_dag_run_types=[DagRunType.MANUAL]. I think we should allow also a single value... It makes things easier and shouldn't be too hard to fix

Sure, that is a nice suggestion. I've updated to support that and also fix some type issue there.

[guan404ming]

Thanks for all the comments. I just updated with @ashb review comments and will handle @jason810496's tomorrow!

[eladkal]

@guan404ming did you address all comments? are we ready to merge?

[guan404ming]

Yes, I think I have resolved all the comments and we could refine it if there is any issue after merging.

[jason810496]

Nice! Thanks for the rapid update!

[guan404ming]

Hi @jason810496, thanks for your great catch. I just updated with your comments.

[jason810496]

Thanks @guan404ming!

[guan404ming]

Thanks!