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.
resource_path=None, method=None, path_params={},
        query_string_params={}, request_context={}):
    try:
        resource_path = resource_path or path
        event = {
            'path': path,
            'headers': dict(headers),
            'pathParameters': dict(path_params),
            'body': payload,
            'isBase64Encoded': False,
            'resource': resource_path,
            'httpMethod': method,
            'queryStringParameters': query_string_params,
            'requestContext': request_context,
            'stageVariables': {}  
        }
        return run_lambda(event=event, context={}, func_arn=func_arn)
    except Exception as e:
        LOG.warning('Unable to run Lambda function on API Gateway message: %s %s' % (e, traceback.format_exc()))
def process_sns_notification(func_arn, topic_arn, subscriptionArn, message, message_attributes, subject='',):
    try:
        event = {
            'Records': [{
                'EventSource': 'localstack:sns',
                'EventVersion': '1.0',
                'EventSubscriptionArn': subscriptionArn,
                'Sns': {
                    'Type': 'Notification',
                    'TopicArn': topic_arn,
                    'Subject': subject,