order_by=rendered_map_index lexicographic sort on map_index when _rendered_map_index is None

[manipatnam]

Under which category would you file this issue?

Airflow Core

Apache Airflow version

3.2.1

What happened and how to reproduce it?

When fetching task instances with order_by=rendered_map_index via:

GET /api/v2/dags/{dag_id}/dagRuns/{run_id}/taskInstances?order_by=rendered_map_index

• Sorting by rendered_map_index over more than 9 mapped instances should return them in
  numeric order (0, 1, 2, ..., 10, 11, ...), not lexicographic order (0, 1, 10, 11, ..., 2, 20, ...)

Operating System

Debian

Deployment

Astronomer

Apache Airflow Provider(s)

No response

Versions of Apache Airflow Providers

No response

Official Helm Chart version

Not Applicable

Kubernetes Version

No response

Helm Chart configuration

No response

Docker Image customizations

No response

Anything else?

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

[Subham-KRLX]

I have confirmed this is a legitimate issue. The rendered_map_index hybrid property is casting map_index to String which causes lexicographic sorting instead of numeric sorting this explains the unexpected order for mapped task instances with retries.