Bug: invocation-type: Event is not supported. RequestResponse is only supported.

[ijtarano]

Description:

It seems like Event in boto3 invoke method doesn't work with SAM Local even when boto3 accept this parameter (https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/lambda/client/invoke.html)

Steps to reproduce:

import boto3
import json 

payload = {
}

lambda_client = boto3.client("lambda", endpoint_url="http://localhost:3001", region_name="eu-west-1")
lambda_function_name = "Lambda"

payload_json = json.dumps(payload)

response = lambda_client.invoke(
    InvocationType="Event", # This Event fails
    FunctionName=lambda_function_name,
    Payload=payload_json
)

Observed result:

ClientError: An error occurred (NotImplemented) when calling the Invoke operation: invocation-type: Event is not supported. RequestResponse is only supported.

Additional environment details (Ex: Windows, Mac, Amazon Linux etc)

1. Amazon Linux:
2. sam --version: SAM CLI, version 1.113.0
3. AWS region: eu-west-1

{
  "version": "1.113.0",
  "system": {
    "python": "3.11.3",
    "os": "Linux-4.14.320-243.544.amzn2.x86_64-x86_64-with-glibc2.26"
  },
  "additional_dependencies": {
    "docker_engine": "20.10.23",
    "aws_cdk": "Not available",
    "terraform": "1.7.2"
  },
  "available_beta_feature_env_vars": [
    "SAM_CLI_BETA_FEATURES",
    "SAM_CLI_BETA_BUILD_PERFORMANCE",
    "SAM_CLI_BETA_TERRAFORM_SUPPORT",
    "SAM_CLI_BETA_RUST_CARGO_LAMBDA"
  ]
}

[lucashuy]

Thanks for opening this issue, just to understand the context here, are you running sam local start-lambda and then passing the endpoint to your script here?

[ijtarano]

Yes, of course, It works perfectly with "RequestResponse" InvocationType parameter ;)

[lucashuy]

Thanks for letting us know, this is something that we guard against since async execution isn't something that is currently implemented. I can tag this issue to a feature request instead.

As an alternative, it's possible to use our sam sync --watch command to deploy to AWS and update code live, similar to how one would use sam local start-lambda. This could be a workaround for now.

[ericbambach-qwickrate]

Bump - this feature is a use-case for us and we want to test async events locally. As a workaround we use RequestResponse but its not ideal.