87 lines
2.5 KiB
Python
87 lines
2.5 KiB
Python
|
#
|
||
|
|
# Copyright 2015 Rackspace, Inc
|
||
|
|
# All Rights Reserved
|
||
|
|
#
|
||
|
|
# 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.
|
||
|
|
|
||
|
|
import os
|
||
|
|
|
||
|
|
import appdirs
|
||
|
|
import dogpile.cache
|
||
|
|
|
||
|
|
|
||
|
|
AUTHOR = 'openstack'
|
||
|
|
PROGNAME = 'python-ironicclient'
|
||
|
|
|
||
|
|
CACHE_DIR = appdirs.user_cache_dir(PROGNAME, AUTHOR)
|
||
|
|
CACHE_FILENAME = os.path.join(CACHE_DIR, 'ironic-api-version.dbm')
|
||
|
|
CACHE = None
|
||
|
|
DEFAULT_EXPIRY = 300 # seconds
|
||
|
|
|
||
|
|
|
||
|
|
def _get_cache():
|
||
|
|
"""Configure file caching."""
|
||
|
|
global CACHE
|
||
|
|
if CACHE is None:
|
||
|
|
|
||
|
|
# Ensure cache directory present
|
||
|
|
if not os.path.exists(CACHE_DIR):
|
||
|
|
os.makedirs(CACHE_DIR)
|
||
|
|
|
||
|
|
CACHE = dogpile.cache.make_region().configure(
|
||
|
|
'dogpile.cache.dbm',
|
||
|
|
expiration_time=DEFAULT_EXPIRY,
|
||
|
|
arguments={
|
||
|
|
"filename": CACHE_FILENAME,
|
||
|
|
}
|
||
|
|
)
|
||
|
|
return CACHE
|
||
|
|
|
||
|
|
|
||
|
|
def _build_key(host, port):
|
||
|
|
"""Build a key based upon the hostname or address supplied."""
|
||
|
|
return "%s:%s" % (host, port)
|
||
|
|
|
||
|
|
|
||
|
|
def save_data(host, port, data):
|
||
|
|
"""Save 'data' for a particular 'host' in the appropriate cache dir.
|
||
|
|
|
||
|
|
param host: The host that we need to save data for
|
||
|
|
param port: The port on the host that we need to save data for
|
||
|
|
param data: The data we want saved
|
||
|
|
"""
|
||
|
|
key = _build_key(host, port)
|
||
|
|
_get_cache().set(key, data)
|
||
|
|
|
||
|
|
|
||
|
|
def retrieve_data(host, port, expiry=None):
|
||
|
|
"""Retrieve the version stored for an ironic 'host', if it's not stale.
|
||
|
|
|
||
|
|
Check to see if there is valid cached data for the host/port
|
||
|
|
combination and return that if it isn't stale.
|
||
|
|
|
||
|
|
param host: The host that we need to retrieve data for
|
||
|
|
param port: The port on the host that we need to retrieve data for
|
||
|
|
param expiry: The age in seconds before cached data is deemed invalid
|
||
|
|
"""
|
||
|
|
# Ensure that a cache file exists first
|
||
|
|
if not os.path.isfile(CACHE_FILENAME):
|
||
|
|
return None
|
||
|
|
|
||
|
|
key = _build_key(host, port)
|
||
|
|
data = _get_cache().get(key, expiration_time=expiry)
|
||
|
|
|
||
|
|
if data == dogpile.cache.api.NO_VALUE:
|
||
|
|
return None
|
||
|
|
return data
|