def handle_ignore_on()

in main.py [0:0]

• 74 lines of code
• 10 McCabe index (conditional complexity)

def handle_ignore_on(logger, ignore_config, jinja_environment,
                     template_variables):
    if 'bucket' not in ignore_config:
        raise NoResendConfigException(
            'No Cloud Storage bucket configured, even though ignoreOn is set!')

    if 'period' not in ignore_config:
        raise NoResendConfigException(
            'No period configured, even though ignoreOn is set!')

    resend_key_hash = hashlib.sha256()
    if 'key' not in ignore_config:
        default_resend_key = template_variables.copy()
        default_resend_key.pop('context')
        resend_key_hash.update(json.dumps(default_resend_key).encode('utf-8'))
    else:
        key_template = jinja_environment.from_string(ignore_config['key'])
        key_template.name = 'resend'
        key_contents = key_template.render()
        resend_key_hash.update(key_contents.encode('utf-8'))

    resend_file = resend_key_hash.hexdigest()
    logger.debug('Checking for ignore object in bucket...',
                 extra={
                     'bucket': ignore_config['bucket'],
                     'blob': resend_file
                 })

    if os.getenv('STORAGE_EMULATOR_HOST'):
        from google.auth.credentials import AnonymousCredentials

        anon_credentials = AnonymousCredentials()
        storage_client = storage.Client(
            client_info=get_grpc_client_info(),
            client_options={"api_endpoint": os.getenv('STORAGE_EMULATOR_HOST')},
            credentials=anon_credentials)
    else:
        storage_client = storage.Client(client_info=get_grpc_client_info())
    bucket = storage_client.bucket(ignore_config['bucket'])
    resend_blob = bucket.blob(resend_file)
    if resend_blob.exists():
        resend_blob.reload()
        resend_period = ignore_config['period']
        resend_period_parsed = parsedatetime.Calendar(
            version=parsedatetime.VERSION_CONTEXT_STYLE).parse(
                resend_period, sourceTime=resend_blob.time_created)
        if len(resend_period_parsed) > 1:
            resend_earliest = datetime.fromtimestamp(
                mktime(resend_period_parsed[0]))
        else:
            resend_earliest = datetime.fromtimestamp(
                mktime(resend_period_parsed))

        if datetime.utcnow() >= resend_earliest:
            logger.info('Ignore period elapsed, reprocessing the message now.',
                        extra={
                            'resend_earliest': resend_earliest,
                            'blob_time_created': resend_blob.time_created
                        })
            resend_blob.upload_from_string('')
        else:
            logger.info(
                'Ignore period not elapsed, not reprocessing the message.',
                extra={
                    'resend_earliest': resend_earliest,
                    'blob_time_created': resend_blob.time_created
                })
            return False
    else:
        try:
            resend_blob.upload_from_string('', if_generation_match=0)
        except Exception as exc:
            # Handle TOCTOU condition
            if 'conditionNotMet' in str(exc):
                logger.warning(
                    'Message processing already in progress (message ignore key already exist).',
                    extra={'exception': exc})
                return False
            else:
                raise exc
    return True