vmware-nsx/neutron/openstack/common/fileutils.py
Gary Kotton ee537e33de Update RPC code from oslo
The common RPC code has been updated to include the following:
    8575d87af49ea276341908f83c8c51db13afca44
    8b2b0b743e84ceed7841cf470afed6a5da8e1d07
    23f602940c64ba408d77ceb8f5ba0f67ee4a18ef
    6d0a6c3083218cdac52758a8b6aac6b03402c658
    7cac1ac1bd9df36d4e5183afac3b643df10b1d4d
    8159efddabb09dd9b7c99963ff7c9de0a6c62b62

Updated to include the following in modules in openstack-common.conf:
py3kcompat, sslutils, and versionutils.

The update also includes imports from the RPC code

Change-Id: I84c5b8e2b17da0018dd69ecb354d123a609afe98
2014-01-15 04:26:57 -08:00

138 lines
3.8 KiB
Python

# Copyright 2011 OpenStack Foundation.
# 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 contextlib
import errno
import os
import tempfile
from neutron.openstack.common import excutils
from neutron.openstack.common.gettextutils import _
from neutron.openstack.common import log as logging
LOG = logging.getLogger(__name__)
_FILE_CACHE = {}
def ensure_tree(path):
"""Create a directory (and any ancestor directories required)
:param path: Directory to create
"""
try:
os.makedirs(path)
except OSError as exc:
if exc.errno == errno.EEXIST:
if not os.path.isdir(path):
raise
else:
raise
def read_cached_file(filename, force_reload=False):
"""Read from a file if it has been modified.
:param force_reload: Whether to reload the file.
:returns: A tuple with a boolean specifying if the data is fresh
or not.
"""
global _FILE_CACHE
if force_reload and filename in _FILE_CACHE:
del _FILE_CACHE[filename]
reloaded = False
mtime = os.path.getmtime(filename)
cache_info = _FILE_CACHE.setdefault(filename, {})
if not cache_info or mtime > cache_info.get('mtime', 0):
LOG.debug(_("Reloading cached file %s") % filename)
with open(filename) as fap:
cache_info['data'] = fap.read()
cache_info['mtime'] = mtime
reloaded = True
return (reloaded, cache_info['data'])
def delete_if_exists(path, remove=os.unlink):
"""Delete a file, but ignore file not found error.
:param path: File to delete
:param remove: Optional function to remove passed path
"""
try:
remove(path)
except OSError as e:
if e.errno != errno.ENOENT:
raise
@contextlib.contextmanager
def remove_path_on_error(path, remove=delete_if_exists):
"""Protect code that wants to operate on PATH atomically.
Any exception will cause PATH to be removed.
:param path: File to work with
:param remove: Optional function to remove passed path
"""
try:
yield
except Exception:
with excutils.save_and_reraise_exception():
remove(path)
def file_open(*args, **kwargs):
"""Open file
see built-in file() documentation for more details
Note: The reason this is kept in a separate module is to easily
be able to provide a stub module that doesn't alter system
state at all (for unit tests)
"""
return file(*args, **kwargs)
def write_to_tempfile(content, path=None, suffix='', prefix='tmp'):
"""Create temporary file or use existing file.
This util is needed for creating temporary file with
specified content, suffix and prefix. If path is not None,
it will be used for writing content. If the path doesn't
exist it'll be created.
:param content: content for temporary file.
:param path: same as parameter 'dir' for mkstemp
:param suffix: same as parameter 'suffix' for mkstemp
:param prefix: same as parameter 'prefix' for mkstemp
For example: it can be used in database tests for creating
configuration files.
"""
if path:
ensure_tree(path)
(fd, path) = tempfile.mkstemp(suffix=suffix, dir=path, prefix=prefix)
try:
os.write(fd, content)
finally:
os.close(fd)
return path