Bug: QueryString Parameters are not coming thru

[94Sip]

Expected Behaviour

I expect to be able to route to the appropriate method and the handling of querystrings to be available to me, depending on how I choose to do Validation, or not.

Current Behaviour

I've tried multiple ways to parse and handle querystring parameters, and neither is working.
The path of /rut/calendar will work (route), regardless of the below methods.
The path of /rut/calendar?yr=2023&mo=11 always fails and gets handled by the not found exception handler, regardless of the below methods

In the code snippet are the 2 separate ways I have tried.

Code snippet

app = APIGatewayRestResolver(cors=cors_config, enable_validation=False)

@app.get("/rut/calendar")
@tracer.capture_method
def get_rut_calendar():
   """Get rut calendar for specific year/month"""
   logger.info("Rut calendar requested")

#---------------------------- using Validation --------------------------------
app = APIGatewayRestResolver(cors=cors_config, enable_validation=True)

@app.get("/rut/calendar")
@tracer.capture_method
def get_rut_calendar(yr: Optional[int] = None, mo: Optional[int] = None):
   """Get rut calendar for specific year/month"""
   logger.info("Rut calendar requested")

Possible Solution

Obviously I think there is a bug with EnableValidation, but the documentation seems to be lacking clarity between the Validation of QueryStrings and the subsequent section on handling querystrings.

Steps to Reproduce

Call the 2 methods with the path I have provided, one with querystrings, and one without

Powertools for AWS Lambda (Python) version

latest

AWS Lambda function runtime

3.12

Packaging format used

Lambda Layers

Debugging logs

Here is the result from CloudWatch:
{
"level": "INFO",
"location": "handle_not_found_errors:333",
"message": "Not found route: /rut/calendar?yr=2023&mo=11",
"timestamp": "2025-06-30 13:02:48,993+0000",
"service": "rut-predictor-api",
"cold_start": true,
"function_name": "TexasRutPredictorProxy",
"function_memory_size": "1024",
"function_arn": "arn:aws:lambda:us-east-2:206693260617:function:TexasRutPredictorProxy",
"function_request_id": "7fcbddf5-f9bb-4d46-9f0b-ad2ef64260e8",
"xray_trace_id": "1-68628adf-01b87d1d2fef9f6b73865206"
}

[leandrodamascena]

Hey @94Sip thanks for opening this issue. I think this is what you're looking for: https://docs.powertools.aws.dev/lambda/python/latest/core/event_handler/api_gateway/#validating-query-strings.

You need to annotate the type with Annotated and Query model and then we can inject the querystring parameters into your function.

Pls let me know if this works.

[94Sip]

Hi, thank you for the reply.

Yes, I haven't tried that, because I was trying to do this: skipping validation

Which is what I was thinking would be "easier". But as I was showing in my bug filing, doesn't work, at least according to what I am seeing.

Also, if I set enable_validation=False, shouldn't I still be able to do this? enable_validation=False