Source code for airflow.contrib.operators.gcs_list_operator

# -*- 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 typing import Iterable

from airflow.contrib.hooks.gcs_hook import GoogleCloudStorageHook
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults


[docs]class GoogleCloudStorageListOperator(BaseOperator): """ List all objects from the bucket with the give string prefix and delimiter in name. This operator returns a python list with the name of objects which can be used by `xcom` in the downstream task. :param bucket: The Google cloud storage bucket to find the objects. (templated) :type bucket: str :param prefix: Prefix string which filters objects whose name begin with this prefix. (templated) :type prefix: str :param delimiter: The delimiter by which you want to filter the objects. (templated) For e.g to lists the CSV files from in a directory in GCS you would use delimiter='.csv'. :type delimiter: str :param google_cloud_storage_conn_id: The connection ID to use when connecting to Google cloud storage. :type google_cloud_storage_conn_id: str :param delegate_to: The account to impersonate, if any. For this to work, the service account making the request must have domain-wide delegation enabled. :type delegate_to: str **Example**: The following Operator would list all the Avro files from ``sales/sales-2017`` folder in ``data`` bucket. :: GCS_Files = GoogleCloudStorageListOperator( task_id='GCS_Files', bucket='data', prefix='sales/sales-2017/', delimiter='.avro', google_cloud_storage_conn_id=google_cloud_conn_id ) """
[docs] template_fields = ('bucket', 'prefix', 'delimiter') # type: Iterable[str]
[docs] ui_color = '#f0eee4'
@apply_defaults def __init__(self, bucket, prefix=None, delimiter=None, google_cloud_storage_conn_id='google_cloud_default', delegate_to=None, *args, **kwargs): super(GoogleCloudStorageListOperator, self).__init__(*args, **kwargs) self.bucket = bucket self.prefix = prefix self.delimiter = delimiter self.google_cloud_storage_conn_id = google_cloud_storage_conn_id self.delegate_to = delegate_to
[docs] def execute(self, context): hook = GoogleCloudStorageHook( google_cloud_storage_conn_id=self.google_cloud_storage_conn_id, delegate_to=self.delegate_to ) self.log.info('Getting list of the files. Bucket: %s; Delimiter: %s; Prefix: %s', self.bucket, self.delimiter, self.prefix) return hook.list(bucket=self.bucket, prefix=self.prefix, delimiter=self.delimiter)

Was this entry helpful?