Unable to set DagRun state in create Dagrun endpoint ("Property is read-only - 'state'")

[SamWheating]

Apache Airflow version

main (development)

What happened

While working on another change I noticed that the example POST from the API docs actually leads to a request Error:

 curl -X POST -H "Cookie: session=xxxx" localhost:8080/api/v1/dags/data_warehouse_dag_5by1a2rogu/dagRuns -d '{"dag_run_id":"string2","logical_date":"2019-08-24T14:15:24Z","execution_date":"2019-08-24T14:15:24Z","conf":{},"state":"queued","note":"strings"}'  -H 'Content-Type: application/json'

{
  "detail": "Property is read-only - 'state'",
  "status": 400,
  "title": "Bad Request",
  "type": "http://apache-airflow-docs.s3-website.eu-central-1.amazonaws.com/docs/apache-airflow/latest/stable-rest-api-ref.html#section/Errors/BadRequest"
}

I believe that this comes from the DagRunSchema marking this field as dump_only:

airflow/airflow/api_connexion/schemas/dag_run_schema.py

Line 69 in 478fd82

state = DagStateField(dump_only=True)

So either -

1. The documentation / API spec is incorrect and this field cannot be set in the request
2. The marshmallow schema is incorrect and this field is incorrectly marked as dump_only

I think that its the former, as there's even a test to ensure that this field can't be set in a request - I can look into this and fix it soon.

What you think should happen instead

The API should accept requested which follow examples from the documentation.

How to reproduce

Spin up breeze and POST a create dagrun request which attempts to set the DagRun state.

Operating System

Breeze

Versions of Apache Airflow Providers

No response

Deployment

Other

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

[hussein-awala]

Usually I use python API to create manual DagRuns, and I set the state without any problem:

dag_run = dag.create_dagrun(
  ...,
  state=DagRunState.QUEUED,  # or DagRunState.RUNNING
  ...,
)

and I think it's the same for the REST API.

You can open a PR and test it. Assigned it to you