Bug: `payload_validation_jmespath` ignores `jmespath_options`, so `powertools_json()` raises Unknown function

[Om-singhaI]

Expected Behaviour

payload_validation_jmespath should accept the same JMESPath functions as event_key_jmespath. The idempotency docs say powertools_json, powertools_base64 and powertools_base64_gzip "are also available to use in this utility".

With the snippet below the handler should run and return {"statusCode": 200, "body": "charged"}. A later call with the same order_id and a changed amount should raise IdempotencyValidationError.

Current Behaviour

Every call fails before the handler runs. What I get:

aws_lambda_powertools.utilities.idempotency.exceptions.IdempotencyPersistenceLayerError: Failed to save in progress record to idempotency store - (Unknown function: powertools_json())

This hits API Gateway handlers, where the payload is a JSON string in body. The docs use powertools_json(body) for the idempotency key, and payload validation is how you catch a changed amount. Use both and no request gets through.

Only the key search passes jmespath_options:

powertools-lambda-python/aws_lambda_powertools/utilities/idempotency/persistence/base.py

Lines 114 to 117 in f872ab8

	data = self.event_key_compiled_jmespath.search(
	data,
	options=jmespath.Options(**(self.jmespath_options or {})),
	)

The payload search doesn't pass any options, so neither the Powertools functions nor custom functions from jmespath_options exist there:

powertools-lambda-python/aws_lambda_powertools/utilities/idempotency/persistence/base.py

Line 160 in f872ab8

data = self.validation_key_jmespath.search(data)

Code snippet

import json

from aws_lambda_powertools.utilities.idempotency import (
    DynamoDBPersistenceLayer,
    IdempotencyConfig,
    idempotent,
)

persistence_layer = DynamoDBPersistenceLayer(table_name="IdempotencyTable")
config = IdempotencyConfig(
    event_key_jmespath="powertools_json(body).order_id",
    payload_validation_jmespath="powertools_json(body).amount",
)


@idempotent(config=config, persistence_store=persistence_layer)
def lambda_handler(event, context):
    return {"statusCode": 200, "body": "charged"}


lambda_handler({"body": json.dumps({"order_id": "o-1", "amount": 100})}, None)

Possible Solution

Pass the same options in _get_hashed_payload:

data = self.validation_key_jmespath.search(
    data,
    options=jmespath.Options(**(self.jmespath_options or {})),
)

I've got the fix with functional tests and will open a PR.

Steps to Reproduce

Run the snippet on develop (f872ab8) with an AWS region set. It fails while hashing the payload, before any DynamoDB call, so you don't need a table or credentials. v3.35.0 has the same line.

Powertools for AWS Lambda (Python) version

3.35.0

AWS Lambda function runtime

3.13

Packaging format used

PyPi

[boring-cyborg]

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[powertools-for-aws-oss-automation]

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