mik-laj commented on a change in pull request #11212: URL: https://github.com/apache/airflow/pull/11212#discussion_r498484961
########## File path: docs/howto/operator/apache/hdfs.rst ########## @@ -0,0 +1,88 @@ + .. 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. + + + +Apache Hadoop(HDFS) Operators +========================== + +`Apache Hadoop HDFS <https://hadoop.apache.org/docs/r1.2.1/hdfs_design.html>`__ is a distributed file system designed to run on commodity hardware. It has many similarities with existing distributed file systems. However, the differences from other distributed file systems are significant. HDFS is highly fault-tolerant and is designed to be deployed on low-cost hardware. HDFS provides high throughput access to application data and is suitable for applications that have large data sets. HDFS relaxes a few POSIX requirements to enable streaming access to file system data. HDFS was originally built as infrastructure for the Apache Nutch web search engine project. HDFS is now an Apache Hadoop subproject. + +.. contents:: + :depth: 1 + :local: + +Prerequisite +------------ + +To use operators, you must configure a :doc:`HDFS Connection <../../connection/hdfs>`. + +.. _howto/operator:HdfsFolderSensor: + +Waits for a non-empty directory +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The :class:`~airflow.providers.apache.hdfs.sensors.hdfs.HdfsFolderSensor` operator is used to check for a non-empty directory in HDFS. + +Use the ``filepath`` parameter to poke until the provided file is found. + +.. exampleinclude:: /../airflow/providers/apache/hdfs/example_dags/ + :language: python + :dedent: 4 + :start-after: [START howto_operator_hdfs_folder_sensor] + :end-before: [END howto_operator_hdfs_folder_sensor] + + +.. _howto/operator:HdfsRegexSensor: + +Waits for matching files by matching on regex +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The :class:`~airflow.providers.apache.hdfs.sensors.hdfs.HdfsRegexSensor` operator is used to check for matching files by matching on regex in HDFS. + +Use the ``filepath`` parameter to mention the keyspace and table for the record. Use dot notation to target a specific keyspace. + +Use the ``regex`` parameter to poke until the provided record is found. + +.. exampleinclude:: /../airflow/providers/apache/hdfs/example_dags/ + :language: python + :dedent: 4 + :start-after: [START howto_operator_hdfs_regex_sensor] + :end-before: [END howto_operator_hdfs_regex_sensor] + + +.. _howto/operator:HdfsSensor: + +Waits for a file or folder to land in HDFS +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The :class:`~airflow.providers.apache.hdfs.sensors.hdfs.HdfsSensor` operator is used to check for a file or folder to land in HDFS. + +Use the ``filepath`` parameter to poke until the provided file is found. + +.. exampleinclude:: /../airflow/providers/apache/hdfs/example_dags/ + :language: python + :dedent: 4 + :start-after: [START howto_operator_hdfs_sensor] + :end-before: [END howto_operator_hdfs_sensor] + + + Review comment: ```suggestion ``` ---------------------------------------------------------------- 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: us...@infra.apache.org
