Steve Baker ad475ee927 Collector which does a simple HTTP GET
This change implements a collector which does an HTTP GET via
python requests to fetch the metadata.

It should work with any GET-able URL, however it is designed to
work with Swift TempURLs.

Swift objects are not consistent, so the Last-Modified header is
checked for each poll and metadata is not fetched if the last
modified is not newer than the previous successful poll.

This collector will be enabled for OS::Nova::Server
software_config_transport: POLL_TEMP_URL which is available
in the Juno release of Heat. Using POLL_TEMP_URL will result
in no metadata polling load on heat, which has historically been
an issue with tripleo scalability.

Change-Id: I22155c22bdcc3c81a5e945ca5436a8f29f196528
2014-10-17 09:40:23 +13:00

63 lines
1.8 KiB
Python

# Copyright (c) 2013 Hewlett-Packard Development Company, L.P.
#
# Licensed 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.
class SourceNotAvailable(RuntimeError):
"""The requested data source is unavailable."""
class SourceNotConfigured(RuntimeError):
"""The requested data source is not configured."""
class Ec2MetadataNotAvailable(SourceNotAvailable):
"""The EC2 metadata service is not available."""
class CfnMetadataNotAvailable(SourceNotAvailable):
"""The cfn metadata service is not available."""
class HeatMetadataNotAvailable(SourceNotAvailable):
"""The heat metadata service is not available."""
class CfnMetadataNotConfigured(SourceNotConfigured):
"""The cfn metadata service is not fully configured."""
class HeatMetadataNotConfigured(SourceNotConfigured):
"""The heat metadata service is not fully configured."""
class HeatLocalMetadataNotAvailable(SourceNotAvailable):
"""The local Heat metadata is not available."""
class LocalMetadataNotAvailable(SourceNotAvailable):
"""The local metadata is not available."""
class RequestMetadataNotAvailable(SourceNotAvailable):
"""The request metadata is not available."""
class RequestMetadataNotConfigured(SourceNotAvailable):
"""The request metadata is not fully configured."""
class InvalidArguments(ValueError):
"""Invalid arguments."""