# -*- 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
[docs]class WebHdfsSensor(BaseSensorOperator):
"""
Waits for a file or folder to land in HDFS
"""
[docs] template_fields = ('filepath',)
@apply_defaults
def __init__(self,
filepath,
webhdfs_conn_id='webhdfs_default',
*args,
**kwargs):
super(WebHdfsSensor, self).__init__(*args, **kwargs)
self.filepath = filepath
self.webhdfs_conn_id = webhdfs_conn_id
[docs] def poke(self, context):
from airflow.hooks.webhdfs_hook import WebHDFSHook
c = WebHDFSHook(self.webhdfs_conn_id)
self.log.info('Poking for file %s', self.filepath)
return c.check_for_path(hdfs_path=self.filepath)