zhongjiajie commented on a change in pull request #4887: [AIRFLOW-4055] Add AWS SQS Sensor URL: https://github.com/apache/airflow/pull/4887#discussion_r268403708
########## File path: airflow/contrib/sensors/aws_sqs_sensor.py ########## @@ -0,0 +1,88 @@ +# -*- coding: utf-8 -*- +# +# 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 airflow.sensors.base_sensor_operator import BaseSensorOperator +from airflow.utils.decorators import apply_defaults +from airflow.contrib.hooks.aws_sqs_hook import SQSHook +from airflow.exceptions import AirflowException + + +class SQSSensor(BaseSensorOperator): + """ + Get messages from an SQS queue and passes them through XCom. + + :param aws_conn_id: AWS connection id + :type aws_conn_id: str + :param sqs_queue: The SQS queue + :type sqs_queue: str + :param max_messages: The maximum number of messages to retrieve for each poke + :type max_messages: int + """ + + template_fields = ('sqs_queue', 'max_messages') + + @apply_defaults + def __init__(self, sqs_queue, aws_conn_id='aws_default', max_messages=5, *args, **kwargs): + super(SQSSensor, self).__init__(*args, **kwargs) + self.sqs_queue = sqs_queue + self.aws_conn_id = aws_conn_id + self.max_messages = max_messages + + def poke(self, context): + """ + Check for message on subscribed queue and write to xcom the message with key ``messages`` + + :param context: the context object + :type context: dict + :return: ``True`` if message is available or ``False`` + """ + + sqs_hook = SQSHook(aws_conn_id=self.aws_conn_id) + self.log.info('SQSSensor checking for message on queue: %s', self.sqs_queue) + + try: + messages = sqs_hook.get_conn().receive_message(QueueUrl=self.sqs_queue, + MaxNumberOfMessages=self.max_messages) + + self.log.info("reveived message %s", str(messages)) + + if 'Messages' not in messages: + self.log.info('No message received %s', str(messages)) + return False + + if len(messages['Messages']) > 0: + context['ti'].xcom_push(key='messages', value=messages) + + entries = [{'Id': message['MessageId'], 'ReceiptHandle': message['ReceiptHandle']} + for message in messages['Messages']] + + result = sqs_hook.get_conn().delete_message_batch(QueueUrl=self.sqs_queue, + Entries=entries) + + if 'Successful' in result: + return True Review comment: Are we have some mistake here? We already push message to Xcom, then if not get `Successful` in L75 will not return `True`. according to that could we move L70 before L79? ```suggestion context['ti'].xcom_push(key='messages', value=messages) return True ``` WDYT? ---------------------------------------------------------------- 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] With regards, Apache Git Services
