# Type of request: This is a ...
[ ] bug report
[x] feature request

# Detailed description
As a Developer,
I want to be able to simulate BadDigest and InvalidDigest errors,
So that I can test the error handling logic

## Expected behavior
https://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html
BadDigest: The Content-MD5 you specified did not match what we received.
InvalidDigest: The Content-MD5 you specified is not valid.

## Actual behavior
localstack returns InvalidDigest when MD5 does not match payload.


dynamodbstreams_api.forward_events(records)
def dynamodb_extract_keys(item, table_name):
    result = {}
    if table_name not in TABLE_DEFINITIONS:
        LOGGER.warning('Unknown table: %s not found in %s' % (table_name, TABLE_DEFINITIONS))
        return None
    for key in TABLE_DEFINITIONS[table_name]['KeySchema']:
        attr_name = key['AttributeName']
        if attr_name not in item:
            return error_response(
                error_type='ValidationException',
                message='One of the required keys was not given a value'
            )
        result[attr_name] = item[attr_name]
    return result
def error_response(message=None, error_type=None, code=400):