TriggerDagRunOperator fails to pass data to other dag in Airflow 3.x

[Aymen1617]

Apache Airflow version

3.1.0

If "Other Airflow 2/3 version" selected, which one?

No response

What happened?

it is not passing data from one dag to another why

What you think should happen instead?

No response

How to reproduce

Steps to Reproduce:

Create a DAG dag_a with a PythonOperator returning a dictionary:

def fetch_job():
return {"job_id": 123, "target_id": 987}

Use TriggerDagRunOperator to trigger another DAG (dag_b) with conf from XCom:

TriggerDagRunOperator(
task_id="trigger_dag_b",
trigger_dag_id="dag_b",
conf="{{ ti.xcom_pull(task_ids='fetch_job') }}"
)

Run the DAG.

Observed Behavior:

Airflow raises a Pydantic ValidationError.

The DAG fails to trigger dag_b.

Cause:

Airflow 3.x strictly validates that conf is a dict.

Using {{ ti.xcom_pull(...) }} without fromjson returns a string, not a dictionary.

Operating System

linux

Versions of Apache Airflow Providers

No response

Deployment

Official Apache Airflow Helm Chart

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.

[Prajwal7842]

Seems duplicate of this #57194

[gopidesupavan]

is this worked on airflow 2.x? i dont think its same in 2.x aswell

[gopidesupavan]

you can return string json object from the task and use it.

@task
def fetch_job():
     return json.dumps({"job_id": 123, "target_id": 987})

[gopidesupavan]

#57214