Source code for airflow.contrib.sensors.ftp_sensor

# -*- 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.
import ftplib
import re

from airflow.contrib.hooks.ftp_hook import FTPHook, FTPSHook
from airflow.sensors.base_sensor_operator import BaseSensorOperator
from airflow.utils.decorators import apply_defaults


[docs]class FTPSensor(BaseSensorOperator): """ Waits for a file or directory to be present on FTP. """
[docs] template_fields = ('path',)
"""Errors that are transient in nature, and where action can be retried"""
[docs] transient_errors = [421, 425, 426, 434, 450, 451, 452]
[docs] error_code_pattern = re.compile(r"([\d]+)")
@apply_defaults def __init__( self, path, ftp_conn_id='ftp_default', fail_on_transient_errors=True, *args, **kwargs): """ Create a new FTP sensor :param path: Remote file or directory path :type path: str :param fail_on_transient_errors: Fail on all errors, including 4xx transient errors. Default True. :type fail_on_transient_errors: bool :param ftp_conn_id: The connection to run the sensor against :type ftp_conn_id: str """ super(FTPSensor, self).__init__(*args, **kwargs) self.path = path self.ftp_conn_id = ftp_conn_id self.fail_on_transient_errors = fail_on_transient_errors
[docs] def _create_hook(self): """Return connection hook.""" return FTPHook(ftp_conn_id=self.ftp_conn_id)
[docs] def _get_error_code(self, e): """Extract error code from ftp exception""" try: matches = self.error_code_pattern.match(str(e)) code = int(matches.group(0)) return code except ValueError: return e
[docs] def poke(self, context): with self._create_hook() as hook: self.log.info('Poking for %s', self.path) try: hook.get_mod_time(self.path) except ftplib.error_perm as e: self.log.info('Ftp error encountered: %s', str(e)) error_code = self._get_error_code(e) if ((error_code != 550) and (self.fail_on_transient_errors or (error_code not in self.transient_errors))): raise e return False return True
[docs]class FTPSSensor(FTPSensor): """Waits for a file or directory to be present on FTP over SSL."""
[docs] def _create_hook(self): """Return connection hook.""" return FTPSHook(ftp_conn_id=self.ftp_conn_id)