Bug: get_parameters_by_name lets botocore ClientError escape instead of GetParameterError #8597

Expected Behaviour

Any failure of the GetParameters call is wrapped in GetParameterError in fail-fast mode, or reported in _errors in graceful mode. The docstring says "Raises GetParameterError upon any error", and get_parameter wraps every exception this way.

Current Behaviour

_get_parameters_by_name_from_batch (ssm.py:628-634) only handles InvalidKeyId and InternalServerError. Throttling or any other ClientError propagates raw in both modes.

Code snippet

from botocore.config import Config
from botocore.stub import Stubber
from aws_lambda_powertools.utilities.parameters import SSMProvider

provider = SSMProvider(boto_config=Config(region_name="us-east-1"))
stub = Stubber(provider.client)
stub.add_client_error("get_parameters", "ThrottlingException")
stub.activate()

provider.get_parameters_by_name({"/a": {}}, raise_on_error=False)  # botocore ClientError, expected {'_errors': ['/a']}
provider.get_parameters_by_name({"/a": {}})                        # botocore ClientError, expected GetParameterError

Possible Solution

Catch Exception around the call; re-raise as GetParameterError when raise_on_error=True, otherwise return the batch names as errors. Code that catches ClientError around this call today is coding against the bug, since every other function in the utility already wraps it.

Steps to Reproduce

Run the snippet above (it uses botocore.stub.Stubber, no AWS access needed).

Powertools for AWS Lambda (Python) version

latest

AWS Lambda function runtime

3.13

Packaging format used

PyPi

Debugging logs