GenericTransfer - Warning: "Placeholder defined in Connection..."

[romanzdk]

Apache Airflow version

2.9.1

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

No response

What happened?

We use GenericTransfer task to copy data from one DB to another. Task is successful but we get a warning in logs:
[2024-05-17, 10:08:43 UTC] {sql.py:187} WARNING - Placeholder defined in Connection 'None' is not listed in 'DEFAULT_SQL_PLACEHOLDERS' and got ignored. Falling back to the default placeholder '%s'.

I checked the Connections in the Admin and everything looks alright.

What you think should happen instead?

No warning log

How to reproduce

create and run GenericTransfer task:

copy_task = GenericTransfer(
	task_id = 'copy_task',
	dag = dag,
	source_conn_id = 'source-db',
	destination_conn_id = 'bi-database',
	sql = '''
		SELECT
			"date"
		FROM "TableName"
	''',
	destination_table = '"TableName"',
	preoperator = '''
		DELETE FROM "TableName"
		WHERE
			1 = 1
	'''
)

Operating System

Debian GNU/Linux 12 (bookworm)

Versions of Apache Airflow Providers

apache-airflow-providers-amazon==8.20.0
apache-airflow-providers-celery==3.6.2
apache-airflow-providers-cncf-kubernetes==8.1.1
apache-airflow-providers-common-io==1.3.1
apache-airflow-providers-common-sql==1.12.0
apache-airflow-providers-fab==1.0.4
apache-airflow-providers-ftp==3.8.0
apache-airflow-providers-http==4.10.1
apache-airflow-providers-imap==3.5.0
apache-airflow-providers-postgres==5.10.2
apache-airflow-providers-smtp==1.6.1
apache-airflow-providers-sqlite==3.7.1

Deployment

Other Docker-based deployment

Deployment details

Airflow 2.9.1, on-premise Kubernetes cluster 1.26.5, python 3.10.12, Celery executor, Postgres 13.13

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

[Taragolis]

cc: @dabla https://github.com/apache/airflow/pull/38528/files#r1551219388

[Taragolis]

I see two problem here:

1. An error in a warning message, instead of connection id use placeholder
2. The warning raised in case if placeholder not defined in connection

[dabla]

I'm on it, will write a test to reproduce but I suppose a None check is missing hence why the warning message.

[dabla]

I've created a PR for this which fixes the issue.