TriggerDagRunLink does not respect base_url when Airflow runs behind a URL prefix

[sadamasin0]

Apache Airflow version

Other Airflow 3 version (please specify below)

If "Other Airflow 3 version" selected, which one?

3.1.3

What happened?

The extra link generated by TriggerDagRunLink (the “Triggered DAG” button) builds a UI URL without honoring base_url setting.
When Airflow is running behind a reverse proxy on a subpath (e.g. /airflow/), the link breaks.

What you think should happen instead?

Extra links should use the same base URL logic documented for reverse proxy deployments.
The reverse proxy guide specifically shows that Airflow must use base_url for correct link generation.

How to reproduce

1. Run Airflow UI behind a prefix, e.g. https://myhost/myorg/airflow/
2. Use TriggerDagRunOperator
3. After the task completes, open Task Details → Extra links
4. Click Triggered DAG → browser attempts to open /dags/... instead of /myorg/airflow/dags/...

Operating System

Red Hat Enterprise Linux 8.10

Versions of Apache Airflow Providers

No response

Deployment

Virtualenv installation

Deployment details

No response

Anything else?

No response

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

[boring-cyborg]

Thanks for opening your first issue here! Be sure to follow the issue template! If you are willing to raise PR to address this issue please do so, no need to wait for approval.

[tirkarthi]

base_url seems to be used in constructing the link. Can you please check if your provider package has this code and add the provider version?

Ref #54218

airflow/providers/standard/src/airflow/providers/standard/operators/trigger_dagrun.py

Line 112 in b9e8fba

return build_airflow_dagrun_url(dag_id=trigger_dag_id, run_id=triggered_dag_run_id)

airflow/airflow-core/src/airflow/utils/helpers.py

Line 196 in b9e8fba

return urljoin(baseurl.rstrip("/") + "/", f"dags/{dag_id}/runs/{run_id}")

[sadamasin0]

@tirkarthi
I have checked provider package and it has the code you pointed.
However issue occurs - I even double checked base_url value in config. It's correct in both api and webserver sections.

apache-airflow-providers-standard==1.10.0

Also, I've inspected link in my browser and it starts with /, so it seems for some reason the fallback was used instead of configured base_url.

[tirkarthi]

Can you please run the below where the api server runs to see value is printed as expected. You can also try calling build_airflow_dagrun_url in the api server to see if base url is considered.

from airflow.configuration import conf
print(conf.get("api", "base_url", fallback="/"))

[sadamasin0]

@tirkarthi
thank you for your input
issue can be closed - we used different kind of Operator in this case, custom one. Issue on our side.

sorry for inconvienience.

[tirkarthi]

No worries, thanks for the confirmation @sadamasin0 .