Bug: [ssm] cannot get more than 10 parameters

[tuanpt-0634]

Expected Behaviour

Follow the example in https://docs.aws.amazon.com/powertools/python/latest/utilities/parameters/#fetching-parameters, when call get_parameters_by_name with more than 10 existed parameters, it should return all those parameters.

Current Behaviour

Return only the last chunk of parameters

Code snippet

from aws_lambda_powertools.utilities.parameters import ssm

params = {
    "/dev/param1": {},
    "/dev/param2": {},
    "/dev/param3": {},
    "/dev/param4": {},
    "/dev/param5": {},
    "/dev/param6": {},
    "/dev/param7": {},
    "/dev/param8": {},
    "/dev/param9": {},
    "/dev/param10": {},
    "/dev/param11": {},
    "/dev/param12": {},
}

response, errors = ssm.get_parameters_by_name(params)

print("Final fetched parameters:", response)
# Actual results: only param11, param12 returned
# Expected results: all params returned

Possible Solution

Bug in method _get_parameters_by_name_in_chunks

powertools-lambda-python/aws_lambda_powertools/utilities/parameters/ssm.py

Lines 572 to 594 in a104ede

	def _get_parameters_by_name_in_chunks(
	self,
	batch: dict[str, dict],
	cache: dict[str, Any],
	raise_on_error: bool,
	decrypt: bool = False,
	) -> tuple[dict, list]:
	"""Take out differences from cache and batch, slice it and fetch from SSM"""
	response: dict[str, Any] = {}
	errors: list[str] = []
	diff = {key: value for key, value in batch.items() if key not in cache}
	for chunk in slice_dictionary(data=diff, chunk_size=self._MAX_GET_PARAMETERS_ITEM):
	response, possible_errors = self._get_parameters_by_name(
	parameters=chunk,
	raise_on_error=raise_on_error,
	decrypt=decrypt,
	)
	response.update(response)
	errors.extend(possible_errors)
	return response, errors

The response variable in line 580 is overridden by the line 586

Steps to Reproduce

See the code snippet

Powertools for AWS Lambda (Python) version

latest

AWS Lambda function runtime

3.13

Packaging format used

PyPi

Debugging logs

[boring-cyborg]

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