dylanbstorey commented on code in PR #30175: URL: https://github.com/apache/airflow/pull/30175#discussion_r1167627022
########## airflow/providers/apache/kafka/sensors/kafka.py: ########## @@ -0,0 +1,219 @@ +# 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. +from __future__ import annotations + +from typing import Any, Callable, Sequence + +from airflow.models import BaseOperator +from airflow.providers.apache.kafka.triggers.await_message import AwaitMessageTrigger + +VALID_COMMIT_CADENCE = {"never", "end_of_batch", "end_of_operator"} + + +class AwaitMessageSensor(BaseOperator): + """An Airflow operator that defers until a specific message is published to Kafka. + + The operator creates a consumer that reads the Kafka log until it encounters a positive event. + + The behavior of the consumer for this trigger is as follows: + - poll the Kafka topics for a message + - if no message returned, sleep + - process the message with provided callable and commit the message offset + - if callable returns any data, raise a TriggerEvent with the return data + - else continue to next message + - return event (as default xcom or specific xcom key) + + + :param kafka_config_id: The connection object to use, defaults to "kafka_default" + :param topics: Topics (or topic regex) to use for reading from + :param apply_function: The function to apply to messages to determine if an event occurred. As a dot + notation string. + :param apply_function_args: Arguments to be applied to the processing function, + defaults to None + :param apply_function_kwargs: Key word arguments to be applied to the processing function, + defaults to None + :param poll_timeout: How long the kafka consumer should wait for a message to arrive from the kafka + cluster,defaults to 1 + :param poll_interval: How long the kafka consumer should sleep after reaching the end of the Kafka log, + defaults to 5 + :param xcom_push_key: the name of a key to push the returned message to, defaults to None + + + """ + + BLUE = "#ffefeb" + ui_color = BLUE + + template_fields = ( + "topics", + "apply_function", + "apply_function_args", + "apply_function_kwargs", + "kafka_config_id", + ) + + def __init__( + self, + topics: Sequence[str], + apply_function: str, + kafka_config_id: str = "kafka_default", + apply_function_args: Sequence[Any] | None = None, + apply_function_kwargs: dict[Any, Any] | None = None, + poll_timeout: float = 1, + poll_interval: float = 5, + xcom_push_key=None, + **kwargs: Any, + ) -> None: + + super().__init__(**kwargs) + + self.topics = topics + self.apply_function = apply_function + self.apply_function_args = apply_function_args + self.apply_function_kwargs = apply_function_kwargs + self.kafka_config_id = kafka_config_id + self.poll_timeout = poll_timeout + self.poll_interval = poll_interval + self.xcom_push_key = xcom_push_key + + def execute(self, context) -> Any: + + self.defer( + trigger=AwaitMessageTrigger( + topics=self.topics, + apply_function=self.apply_function, + apply_function_args=self.apply_function_args, + apply_function_kwargs=self.apply_function_kwargs, + kafka_config_id=self.kafka_config_id, + poll_timeout=self.poll_timeout, + poll_interval=self.poll_interval, + ), + method_name="execute_complete", + ) + + def execute_complete(self, context, event=None): + if self.xcom_push_key: + self.xcom_push(context, key=self.xcom_push_key, value=event) + return event + + +class AwaitMessageTriggerFunctionSensor(BaseOperator): + """An Airflow operator that defers until a specific message is published to + Kafka, then triggers a registered function + + + The behavior of the consumer for this trigger is as follows: + - poll the Kafka topics for a message + - if no message returned, sleep + - process the message with provided callable and commit the message offset + - if callable returns any data, raise a TriggerEvent with the return data + - else continue to next message + - return event (as default xcom or specific xcom key) + + + :param kafka_config_id: The connection object to use, defaults to "kafka_default" + :param topics: Topics (or topic regex) to use for reading from + :param apply_function: The function to apply to messages to determine if an event occurred. As a dot + notation string. + :param event_triggered_function: The callable to trigger once the apply_function encounters a + positive event. + :param apply_function_args: Arguments to be applied to the processing function, defaults to None + :param apply_function_kwargs: Key word arguments to be applied to the processing function, + defaults to None + :param poll_timeout: How long the kafka consumer should wait for a message to arrive from the kafka + cluster, defaults to 1 + :param poll_interval: How long the kafka consumer should sleep after reaching the end of the Kafka log, + defaults to 5 + :param xcom_push_key: the name of a key to push the returned message to, defaults to None Review Comment: Good eye. -- 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. 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