NicolasBearingPoint opened a new issue, #50491: URL: https://github.com/apache/airflow/issues/50491
### Apache Airflow version 2.10.5 ### If "Other Airflow 2 version" selected, which one? _No response_ ### What happened? I'm encountering an issue when deserializing XComs using a custom XCom backend that loads data from S3 using `S3Hook(aws_conn_id='aws')`. `aws` is the connection Id defined with the aws credentials. The same code is working for Airflow 2.10.4 but not anymore from 2.10.5 and further. Despite having a valid AWS connection configured in Airflow (visible and **working well** in **ALL** other parts of the DAG), I get the following error during deserialization steps: ```botocore.exceptions.NoCredentialsError: Unable to locate credentials```` With the function: ``` hook = S3Hook(aws_conn_id='aws') head_object = hook.head_object(key=key, bucket_name=CustomXComBackendPandas.get_bucket_name()) ``` This error is not visible in the Airflow UI but I found it in the scheduler container's logs. The branching task is set as success but the following branched task is queued 'forever'. After switching to manual session initialization using `boto3.Session(...)`, I still have the same error... ### What you think should happen instead? The 'aws' connection is not resolved correctly anymore by the scheduler, even though it is defined in Airflow. ### How to reproduce ``` class CustomXComBackendPandas(BaseXCom): XCOM_PREFIX = "xcom_s3://" S3_PATH_PREFIX = "tmp" _BUCKET_NAME = "" DATAFRAME_EXTENSION = ".parquet" @staticmethod def deserialize_value(result: BaseXCom) -> Any: hook = S3Hook(aws_conn_id='aws') head_object = hook.head_object(key='key', bucket_name='bucket') ``` ### Operating System macOS 15.4.1 (Sonoma) ### Versions of Apache Airflow Providers _No response_ ### Deployment Astronomer ### 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 - [x] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@airflow.apache.org.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org