serkef commented on a change in pull request #7407: URL: https://github.com/apache/airflow/pull/7407#discussion_r420893451
########## File path: airflow/providers/apache/kafka/sensors/kafka_sensor.py ########## @@ -0,0 +1,76 @@ +# +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + +import logging + +from cached_property import cached_property + +from airflow.providers.apache.kafka.hooks.kafka_consumer_hook import KafkaConsumerHook +from airflow.sensors.base_sensor_operator import BaseSensorOperator +from airflow.utils.decorators import apply_defaults + + +class KafkaSensor(BaseSensorOperator): + """ + Consumes the Kafka message with the specific topic + """ + DEFAULT_HOST = 'kafka1' + DEFAULT_PORT = 9092 + templated_fields = ('topic', + 'host', + 'port', + ) + + @apply_defaults + def __init__(self, topic, host=DEFAULT_HOST, port=DEFAULT_PORT, *args, **kwargs): + """ + Initialize the sensor, the connection establish + is put off to it's first time usage. + :param conn_id: + the kafka broker connection whom this sensor + subscripts against. + :param topic: + the subscribed topic + """ + self.topic = topic + self.host = host + self.port = port + super(KafkaSensor, self).__init__(*args, **kwargs) + + @cached_property + def hook(self): + """ + + :return: + KafkaConsumerHook + """ + return KafkaConsumerHook(self.topic, self.host, self.port) + + def poke(self, context): + logging.info( + 'Poking topic: %s, using hook: %s', + str(self.topic), str(self.hook)) + + messages = self.hook.get_messages() + + if not messages: Review comment: hm maybe the check is the opposite? if no messages, return false ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
