I'm trying to setup an lambda function triggered by S3 events within a localstack docker-compose environment.
I've got the latest localstack image running in one service with S3, Lambda and APIGATEWAY and the second service is using `awslocal` to communicate with the localstack.

I have gotten as far as successfully creating a lambda function but when I attempt to `add-permission` I get a 404 Not Found error.

My command is:
```
awslocal lambda add-permission 
--function-name my-lambda-function 
--action lambda:InvokeFunction 
--statement-id s3 
--principal s3.amazonaws.com 
--source-arn arn:aws:s3:::event-source-bucket
```

This works against AWS so I'm not sure what I need to have setup within localstack to get it working.  Thanks for any insight you may have.
delimiter = '.'
    if runtime.startswith(LAMBDA_RUNTIME_NODEJS):
        file_ext = '.js'
    elif runtime.startswith(LAMBDA_RUNTIME_GOLANG):
        file_ext = ''
    elif runtime.startswith(LAMBDA_RUNTIME_DOTNETCORE2) or runtime.startswith(LAMBDA_RUNTIME_DOTNETCORE21):
        file_ext = '.dll'
        delimiter = ':'
    elif runtime.startswith(LAMBDA_RUNTIME_RUBY):
        file_ext = '.rb'
    elif runtime.startswith(LAMBDA_RUNTIME_CUSTOM_RUNTIME):
        file_ext = '.sh'
    else:
        file_ext = '.py'
    return '%s%s' % (handler_name.split(delimiter)[0], file_ext)
def get_handler_function_from_name(handler_name, runtime=LAMBDA_DEFAULT_RUNTIME):