Chetan Risbud a71ab7b9b7 Updating copyrights with current year
Copyrights are updated across the code to reflect 2013.
Copyrights message was added to couple of scripts.

Change-Id: I2cfc7bdc6adaa5c9ab0075aab49021a5f0dea7a1
Signed-off-by: Chetan Risbud <crisbud@redhat.com>
Reviewed-on: http://review.gluster.org/5371
Reviewed-by: Luis Pabon <lpabon@redhat.com>
Tested-by: Luis Pabon <lpabon@redhat.com>
2013-07-24 18:43:52 -07:00

773 lines
33 KiB
Python

# Copyright (c) 2012-2013 Red Hat, Inc.
#
# 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 stat
import fcntl
import errno
import random
import logging
from hashlib import md5
from eventlet import sleep
from contextlib import contextmanager
from swift.common.utils import TRUE_VALUES, fallocate
from swift.common.exceptions import DiskFileNotExist, DiskFileError
from gluster.swift.common.exceptions import GlusterFileSystemOSError
from gluster.swift.common.fs_utils import do_fstat, do_open, do_close, \
do_unlink, do_chown, os_path, do_fsync, do_fchown, do_stat
from gluster.swift.common.utils import read_metadata, write_metadata, \
validate_object, create_object_metadata, rmobjdir, dir_is_object, \
get_object_metadata
from gluster.swift.common.utils import X_CONTENT_LENGTH, X_CONTENT_TYPE, \
X_TIMESTAMP, X_TYPE, X_OBJECT_TYPE, FILE, OBJECT, DIR_TYPE, \
FILE_TYPE, DEFAULT_UID, DEFAULT_GID, DIR_NON_OBJECT, DIR_OBJECT
from ConfigParser import ConfigParser, NoSectionError, NoOptionError
from swift.obj.server import DiskFile
# FIXME: Hopefully we'll be able to move to Python 2.7+ where O_CLOEXEC will
# be back ported. See http://www.python.org/dev/peps/pep-0433/
O_CLOEXEC = 02000000
DEFAULT_DISK_CHUNK_SIZE = 65536
# keep these lower-case
DISALLOWED_HEADERS = set('content-length content-type deleted etag'.split())
def _random_sleep():
sleep(random.uniform(0.5, 0.15))
def _lock_parent(full_path):
parent_path, _ = full_path.rsplit(os.path.sep, 1)
try:
fd = os.open(parent_path, os.O_RDONLY | O_CLOEXEC)
except OSError as err:
if err.errno == errno.ENOENT:
# Cannot lock the parent because it does not exist, let the caller
# handle this situation.
return False
raise
else:
while True:
# Spin sleeping for 1/10th of a second until we get the lock.
# FIXME: Consider adding a final timeout just abort the operation.
try:
fcntl.flock(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
except IOError as err:
if err.errno == errno.EAGAIN:
_random_sleep()
else:
# Don't leak an open file on an exception
os.close(fd)
raise
except Exception:
# Don't leak an open file for any other exception
os.close(fd)
raise
else:
break
return fd
def _make_directory_locked(full_path, uid, gid, metadata=None):
fd = _lock_parent(full_path)
if fd is False:
# Parent does not exist either, pass this situation on to the caller
# to handle.
return False, metadata
try:
# Check for directory existence
stats = do_stat(full_path)
if stats:
# It now exists, having acquired the lock of its parent directory,
# but verify it is actually a directory
is_dir = stat.S_ISDIR(stats.st_mode)
if not is_dir:
# It is not a directory!
raise DiskFileError("_make_directory_locked: non-directory"
" found at path %s when expecting a"
" directory", full_path)
return True, metadata
# We know the parent directory exists, and we have it locked, attempt
# the creation of the target directory.
return _make_directory_unlocked(full_path, uid, gid, metadata=metadata)
finally:
# We're done here, be sure to remove our lock and close our open FD.
try:
fcntl.flock(fd, fcntl.LOCK_UN)
except:
pass
os.close(fd)
def _make_directory_unlocked(full_path, uid, gid, metadata=None):
"""
Make a directory and change the owner ship as specified, and potentially
creating the object metadata if requested.
"""
try:
os.mkdir(full_path)
except OSError as err:
if err.errno == errno.ENOENT:
# Tell the caller some directory of the parent path does not
# exist.
return False, metadata
elif err.errno == errno.EEXIST:
# Possible race, in that the caller invoked this method when it
# had previously determined the file did not exist.
#
# FIXME: When we are confident, remove this stat() call as it is
# not necessary.
try:
stats = os.stat(full_path)
except OSError as serr:
# FIXME: Ideally we'd want to return an appropriate error
# message and code in the PUT Object REST API response.
raise DiskFileError("_make_directory_unlocked: os.mkdir failed"
" because path %s already exists, and"
" a subsequent os.stat on that same"
" path failed (%s)" % (full_path,
str(serr)))
else:
is_dir = stat.S_ISDIR(stats.st_mode)
if not is_dir:
# FIXME: Ideally we'd want to return an appropriate error
# message and code in the PUT Object REST API response.
raise DiskFileError("_make_directory_unlocked: os.mkdir"
" failed on path %s because it already"
" exists but not as a directory" % (
full_path))
return True, metadata
elif err.errno == errno.ENOTDIR:
# FIXME: Ideally we'd want to return an appropriate error
# message and code in the PUT Object REST API response.
raise DiskFileError("_make_directory_unlocked: os.mkdir failed"
" because some part of path %s is not in fact"
" a directory" % (full_path))
elif err.errno == errno.EIO:
# Sometimes Fuse will return an EIO error when it does not know
# how to handle an unexpected, but transient situation. It is
# possible the directory now exists, stat() it to find out after a
# short period of time.
_random_sleep()
try:
stats = os.stat(full_path)
except OSError as serr:
if serr.errno == errno.ENOENT:
errmsg = "_make_directory_unlocked: os.mkdir failed on" \
" path %s (EIO), and a subsequent os.stat on" \
" that same path did not find the file." % (
full_path,)
else:
errmsg = "_make_directory_unlocked: os.mkdir failed on" \
" path %s (%s), and a subsequent os.stat on" \
" that same path failed as well (%s)" % (
full_path, str(err), str(serr))
raise DiskFileError(errmsg)
else:
# The directory at least exists now
is_dir = stat.S_ISDIR(stats.st_mode)
if is_dir:
# Dump the stats to the log with the original exception.
logging.warn("_make_directory_unlocked: os.mkdir initially"
" failed on path %s (%s) but a stat()"
" following that succeeded: %r" % (full_path,
str(err),
stats))
# Assume another entity took care of the proper setup.
return True, metadata
else:
raise DiskFileError("_make_directory_unlocked: os.mkdir"
" initially failed on path %s (%s) but"
" now we see that it exists but is not"
" a directory (%r)" % (full_path,
str(err),
stats))
else:
# Some other potentially rare exception occurred that does not
# currently warrant a special log entry to help diagnose.
raise DiskFileError("_make_directory_unlocked: os.mkdir failed on"
" path %s (%s)" % (full_path, str(err)))
else:
if metadata:
# We were asked to set the initial metadata for this object.
metadata_orig = get_object_metadata(full_path)
metadata_orig.update(metadata)
write_metadata(full_path, metadata_orig)
metadata = metadata_orig
# We created it, so we are reponsible for always setting the proper
# ownership.
do_chown(full_path, uid, gid)
return True, metadata
_fs_conf = ConfigParser()
if _fs_conf.read(os.path.join('/etc/swift', 'fs.conf')):
try:
_mkdir_locking = _fs_conf.get('DEFAULT', 'mkdir_locking', "no") \
in TRUE_VALUES
except (NoSectionError, NoOptionError):
_mkdir_locking = False
try:
_use_put_mount = _fs_conf.get('DEFAULT', 'use_put_mount', "no") \
in TRUE_VALUES
except (NoSectionError, NoOptionError):
_use_put_mount = False
try:
_relaxed_writes = _fs_conf.get('DEFAULT', 'relaxed_writes', "no") \
in TRUE_VALUES
except (NoSectionError, NoOptionError):
_relaxed_writes = False
try:
_preallocate = _fs_conf.get('DEFAULT', 'preallocate', "no") \
in TRUE_VALUES
except (NoSectionError, NoOptionError):
_preallocate = False
else:
_mkdir_locking = False
_use_put_mount = False
_relaxed_writes = False
_preallocate = False
if _mkdir_locking:
make_directory = _make_directory_locked
else:
make_directory = _make_directory_unlocked
def _adjust_metadata(metadata):
# Fix up the metadata to ensure it has a proper value for the
# Content-Type metadata, as well as an X_TYPE and X_OBJECT_TYPE
# metadata values.
content_type = metadata[X_CONTENT_TYPE]
if not content_type:
# FIXME: How can this be that our caller supplied us with metadata
# that has a content type that evaluates to False?
#
# FIXME: If the file exists, we would already know it is a
# directory. So why are we assuming it is a file object?
metadata[X_CONTENT_TYPE] = FILE_TYPE
metadata[X_OBJECT_TYPE] = FILE
else:
if content_type.lower() == DIR_TYPE:
metadata[X_OBJECT_TYPE] = DIR_OBJECT
else:
metadata[X_OBJECT_TYPE] = FILE
metadata[X_TYPE] = OBJECT
return metadata
class Gluster_DiskFile(DiskFile):
"""
Manage object files on disk.
Object names ending or beginning with a '/' as in /a, a/, /a/b/,
etc, or object names with multiple consecutive slahes, like a//b,
are not supported. The proxy server's contraints filter
gluster.common.constrains.gluster_check_object_creation() should
reject such requests.
:param path: path to devices on the node/mount path for UFO.
:param device: device name/account_name for UFO.
:param partition: partition on the device the object lives in
:param account: account name for the object
:param container: container name for the object
:param obj: object name for the object
:param logger: logger object for writing out log file messages
:param keep_data_fp: if True, don't close the fp, otherwise close it
:param disk_chunk_Size: size of chunks on file reads
:param uid: user ID disk object should assume (file or directory)
:param gid: group ID disk object should assume (file or directory)
"""
def __init__(self, path, device, partition, account, container, obj,
logger, keep_data_fp=False,
disk_chunk_size=DEFAULT_DISK_CHUNK_SIZE,
uid=DEFAULT_UID, gid=DEFAULT_GID, iter_hook=None):
self.disk_chunk_size = disk_chunk_size
self.iter_hook = iter_hook
obj = obj.strip(os.path.sep)
if os.path.sep in obj:
self._obj_path, self._obj = os.path.split(obj)
else:
self._obj_path = ''
self._obj = obj
if self._obj_path:
self.name = os.path.join(container, self._obj_path)
else:
self.name = container
# Absolute path for object directory.
self.datadir = os.path.join(path, device, self.name)
self.device_path = os.path.join(path, device)
self._container_path = os.path.join(path, device, container)
if _use_put_mount:
self.put_datadir = os.path.join(self.device_path + '_PUT',
self.name)
else:
self.put_datadir = self.datadir
self._is_dir = False
self.tmppath = None
self.logger = logger
self.metadata = {}
self.meta_file = None
self.fp = None
self.iter_etag = None
self.started_at_0 = False
self.read_to_eof = False
self.quarantined_dir = None
self.keep_cache = False
self.uid = int(uid)
self.gid = int(gid)
self.suppress_file_closing = False
# Don't store a value for data_file until we know it exists.
self.data_file = None
data_file = os.path.join(self.put_datadir, self._obj)
try:
stats = do_stat(data_file)
except OSError as err:
if err.errno == errno.ENOTDIR:
return
else:
if not stats:
return
self.data_file = data_file
self._is_dir = stat.S_ISDIR(stats.st_mode)
self.metadata = read_metadata(data_file)
if not self.metadata:
create_object_metadata(data_file)
self.metadata = read_metadata(data_file)
if not validate_object(self.metadata):
create_object_metadata(data_file)
self.metadata = read_metadata(data_file)
self.filter_metadata()
if not self._is_dir and keep_data_fp:
# The caller has an assumption that the "fp" field of this
# object is an file object if keep_data_fp is set. However,
# this implementation of the DiskFile object does not need to
# open the file for internal operations. So if the caller
# requests it, we'll just open the file for them.
self.fp = do_open(data_file, 'rb')
def close(self, verify_file=True):
"""
Close the file. Will handle quarantining file if necessary.
:param verify_file: Defaults to True. If false, will not check
file to see if it needs quarantining.
"""
# Marker directory
if self._is_dir:
assert not self.fp
return
if self.fp:
do_close(self.fp)
self.fp = None
def is_deleted(self):
"""
Check if the file is deleted.
:returns: True if the file doesn't exist or has been flagged as
deleted.
"""
return not self.data_file
def _create_dir_object(self, dir_path, metadata=None):
"""
Create a directory object at the specified path. No check is made to
see if the directory object already exists, that is left to the
caller (this avoids a potentially duplicate stat() system call).
The "dir_path" must be relative to its container, self._container_path.
The "metadata" object is an optional set of metadata to apply to the
newly created directory object. If not present, no initial metadata is
applied.
The algorithm used is as follows:
1. An attempt is made to create the directory, assuming the parent
directory already exists
* Directory creation races are detected, returning success in
those cases
2. If the directory creation fails because some part of the path to
the directory does not exist, then a search back up the path is
performed to find the first existing ancestor directory, and then
the missing parents are successively created, finally creating
the target directory
"""
full_path = os.path.join(self._container_path, dir_path)
cur_path = full_path
stack = []
while True:
md = None if cur_path != full_path else metadata
ret, newmd = make_directory(cur_path, self.uid, self.gid, md)
if ret:
break
# Some path of the parent did not exist, so loop around and
# create that, pushing this parent on the stack.
if os.path.sep not in cur_path:
raise DiskFileError("DiskFile._create_dir_object(): failed to"
" create directory path while exhausting"
" path elements to create: %s" % full_path)
cur_path, child = cur_path.rsplit(os.path.sep, 1)
assert child
stack.append(child)
child = stack.pop() if stack else None
while child:
cur_path = os.path.join(cur_path, child)
md = None if cur_path != full_path else metadata
ret, newmd = make_directory(cur_path, self.uid, self.gid, md)
if not ret:
raise DiskFileError("DiskFile._create_dir_object(): failed to"
" create directory path to target, %s,"
" on subpath: %s" % (full_path, cur_path))
child = stack.pop() if stack else None
return True, newmd
def put_metadata(self, metadata, tombstone=False):
"""
Short hand for putting metadata to .meta and .ts files.
:param metadata: dictionary of metadata to be written
:param tombstone: whether or not we are writing a tombstone
"""
if tombstone:
# We don't write tombstone files. So do nothing.
return
assert self.data_file is not None, \
"put_metadata: no file to put metadata into"
metadata = _adjust_metadata(metadata)
write_metadata(self.data_file, metadata)
self.metadata = metadata
self.filter_metadata()
def put(self, fd, metadata, extension='.data'):
"""
Finalize writing the file on disk, and renames it from the temp file
to the real location. This should be called after the data has been
written to the temp file.
:param fd: file descriptor of the temp file
:param metadata: dictionary of metadata to be written
:param extension: extension to be used when making the file
"""
# Our caller will use '.data' here; we just ignore it since we map the
# URL directly to the file system.
metadata = _adjust_metadata(metadata)
if dir_is_object(metadata):
if not self.data_file:
# Does not exist, create it
data_file = os.path.join(self._obj_path, self._obj)
_, self.metadata = self._create_dir_object(data_file, metadata)
self.data_file = os.path.join(self._container_path, data_file)
elif not self.is_dir:
# Exists, but as a file
raise DiskFileError('DiskFile.put(): directory creation failed'
' since the target, %s, already exists as'
' a file' % self.data_file)
return
if self._is_dir:
# A pre-existing directory already exists on the file
# system, perhaps gratuitously created when another
# object was created, or created externally to Swift
# REST API servicing (UFO use case).
raise DiskFileError('DiskFile.put(): file creation failed since'
' the target, %s, already exists as a'
' directory' % self.data_file)
# Write out metadata before fsync() to ensure it is also forced to
# disk.
write_metadata(fd, metadata)
if not _relaxed_writes:
do_fsync(fd)
if X_CONTENT_LENGTH in metadata:
# Don't bother doing this before fsync in case the OS gets any
# ideas to issue partial writes.
fsize = int(metadata[X_CONTENT_LENGTH])
self.drop_cache(fd, 0, fsize)
# At this point we know that the object's full directory path exists,
# so we can just rename it directly without using Swift's
# swift.common.utils.renamer(), which makes the directory path and
# adds extra stat() calls.
data_file = os.path.join(self.put_datadir, self._obj)
while True:
try:
os.rename(self.tmppath, data_file)
except OSError as err:
if err.errno in (errno.ENOENT, errno.EIO):
# FIXME: Why either of these two error conditions is
# happening is unknown at this point. This might be a FUSE
# issue of some sort or a possible race condition. So
# let's sleep on it, and double check the environment
# after a good nap.
_random_sleep()
# Tease out why this error occurred. The man page for
# rename reads:
# "The link named by tmppath does not exist; or, a
# directory component in data_file does not exist;
# or, tmppath or data_file is an empty string."
assert len(self.tmppath) > 0 and len(data_file) > 0
tpstats = do_stat(self.tmppath)
tfstats = do_fstat(fd)
assert tfstats
if not tpstats or tfstats.st_ino != tpstats.st_ino:
# Temporary file name conflict
raise DiskFileError('DiskFile.put(): temporary file,'
' %s, was already renamed'
' (targeted for %s)' % (
self.tmppath, data_file))
else:
# Data file target name now has a bad path!
dfstats = do_stat(self.put_datadir)
if not dfstats:
raise DiskFileError('DiskFile.put(): path to'
' object, %s, no longer exists'
' (targeted for %s)' % (
self.put_datadir,
data_file))
else:
is_dir = stat.S_ISDIR(dfstats.st_mode)
if not is_dir:
raise DiskFileError('DiskFile.put(): path to'
' object, %s, no longer a'
' directory (targeted for'
' %s)' % (self.put_datadir,
data_file))
else:
# Let's retry since everything looks okay
logging.warn("DiskFile.put(): os.rename('%s',"
"'%s') initially failed (%s) but"
" a stat('%s') following that"
" succeeded: %r" % (
self.tmppath, data_file,
str(err), self.put_datadir,
dfstats))
continue
else:
raise GlusterFileSystemOSError(
err.errno, "%s, os.rename('%s', '%s')" % (
err.strerror, self.tmppath, data_file))
else:
# Success!
break
# Avoid the unlink() system call as part of the mkstemp context cleanup
self.tmppath = None
self.metadata = metadata
self.filter_metadata()
# Mark that it actually exists now
self.data_file = os.path.join(self.datadir, self._obj)
def unlinkold(self, timestamp):
"""
Remove any older versions of the object file. Any file that has an
older timestamp than timestamp will be deleted.
:param timestamp: timestamp to compare with each file
"""
if not self.metadata or self.metadata[X_TIMESTAMP] >= timestamp:
return
assert self.data_file, \
"Have metadata, %r, but no data_file" % self.metadata
if self._is_dir:
# Marker, or object, directory.
#
# Delete from the filesystem only if it contains
# no objects. If it does contain objects, then just
# remove the object metadata tag which will make this directory a
# fake-filesystem-only directory and will be deleted
# when the container or parent directory is deleted.
metadata = read_metadata(self.data_file)
if dir_is_object(metadata):
metadata[X_OBJECT_TYPE] = DIR_NON_OBJECT
write_metadata(self.data_file, metadata)
rmobjdir(self.data_file)
else:
# Delete file object
do_unlink(self.data_file)
# Garbage collection of non-object directories.
# Now that we deleted the file, determine
# if the current directory and any parent
# directory may be deleted.
dirname = os.path.dirname(self.data_file)
while dirname and dirname != self._container_path:
# Try to remove any directories that are not
# objects.
if not rmobjdir(dirname):
# If a directory with objects has been
# found, we can stop garabe collection
break
else:
dirname = os.path.dirname(dirname)
self.metadata = {}
self.data_file = None
def get_data_file_size(self):
"""
Returns the os_path.getsize for the file. Raises an exception if this
file does not match the Content-Length stored in the metadata, or if
self.data_file does not exist.
:returns: file size as an int
:raises DiskFileError: on file size mismatch.
:raises DiskFileNotExist: on file not existing (including deleted)
"""
#Marker directory.
if self._is_dir:
return 0
try:
file_size = 0
if self.data_file:
file_size = os_path.getsize(self.data_file)
if X_CONTENT_LENGTH in self.metadata:
metadata_size = int(self.metadata[X_CONTENT_LENGTH])
if file_size != metadata_size:
self.metadata[X_CONTENT_LENGTH] = file_size
write_metadata(self.data_file, self.metadata)
return file_size
except OSError as err:
if err.errno != errno.ENOENT:
raise
raise DiskFileNotExist('Data File does not exist.')
def filter_metadata(self):
if X_TYPE in self.metadata:
self.metadata.pop(X_TYPE)
if X_OBJECT_TYPE in self.metadata:
self.metadata.pop(X_OBJECT_TYPE)
@contextmanager
def mkstemp(self, size=None):
"""
Contextmanager to make a temporary file, optionally of a specified
initial size.
For Gluster, we first optimistically create the temporary file using
the "rsync-friendly" .NAME.random naming. If we find that some path to
the file does not exist, we then create that path and then create the
temporary file again. If we get file name conflict, we'll retry using
different random suffixes 1,000 times before giving up.
"""
data_file = os.path.join(self.put_datadir, self._obj)
# Assume the full directory path exists to the file already, and
# construct the proper name for the temporary file.
for i in range(0, 1000):
tmpfile = '.' + self._obj + '.' + md5(self._obj +
str(random.random())).hexdigest()
tmppath = os.path.join(self.put_datadir, tmpfile)
try:
fd = do_open(tmppath,
os.O_WRONLY | os.O_CREAT | os.O_EXCL | O_CLOEXEC)
except GlusterFileSystemOSError as gerr:
if gerr.errno == errno.EEXIST:
# Retry with a different random number.
continue
if gerr.errno == errno.EIO:
# FIXME: Possible FUSE issue or race condition, let's
# sleep on it and retry the operation.
_random_sleep()
logging.warn("DiskFile.mkstemp(): %s ... retrying in"
" 0.1 secs", gerr)
continue
if gerr.errno != errno.ENOENT:
# FIXME: Other cases we should handle?
raise
if not self._obj_path:
# No directory hierarchy and the create failed telling us
# the container or volume directory does not exist. This
# could be a FUSE issue or some race condition, so let's
# sleep a bit and retry.
_random_sleep()
logging.warn("DiskFile.mkstemp(): %s ... retrying in"
" 0.1 secs", gerr)
continue
if i != 0:
# Got ENOENT after previously making the path. This could
# also be a FUSE issue or some race condition, nap and
# retry.
_random_sleep()
logging.warn("DiskFile.mkstemp(): %s ... retrying in"
" 0.1 secs" % gerr)
continue
# It looks like the path to the object does not already exist
self._create_dir_object(self._obj_path)
continue
else:
break
else:
# We failed after 1,000 attempts to create the temporary file.
raise DiskFileError('DiskFile.mkstemp(): failed to successfully'
' create a temporary file without running'
' into a name conflict after 1,000 attempts'
' for: %s' % (data_file,))
self.tmppath = tmppath
try:
# Ensure it is properly owned before we make it available.
do_fchown(fd, self.uid, self.gid)
if _preallocate and size:
# For XFS, fallocate() turns off speculative pre-allocation
# until a write is issued either to the last block of the file
# before the EOF or beyond the EOF. This means that we are
# less likely to fragment free space with pre-allocated
# extents that get truncated back to the known file size.
# However, this call also turns holes into allocated but
# unwritten extents, so that allocation occurs before the
# write, not during XFS writeback. This effectively defeats
# any allocation optimizations the filesystem can make at
# writeback time.
fallocate(fd, size)
yield fd
finally:
try:
do_close(fd)
except OSError:
pass
if self.tmppath:
tmppath, self.tmppath = self.tmppath, None
do_unlink(tmppath)