#
# 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.
#
"""Fetches GCE metadata if the calling process is running on a GCE VM."""
# pytype: skip-file
import requests
BASE_METADATA_URL = "http://metadata/computeMetadata/v1/"
def _fetch_metadata(key):
try:
headers = {"Metadata-Flavor": "Google"}
uri = BASE_METADATA_URL + key
resp = requests.get(uri, headers=headers, timeout=5) # 5 seconds.
if resp.status_code == 200:
return resp.text
except requests.exceptions.RequestException:
# Silently fail, may mean its running on a non DataflowRunner,
# in which case it's prefectly normal.
pass
return ""
def _fetch_custom_gce_metadata(customMetadataKey):
return _fetch_metadata("instance/attributes/" + customMetadataKey)
[docs]
def fetch_dataflow_job_id():
return _fetch_custom_gce_metadata("job_id")