text: # Copyright (c) 2010-2012 OpenStack, LLC.
  #
  # 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.
  
  """ Object Server for Swift """
  
  from __future__ import with_statement
  import cPickle as pickle
  import errno
  import os
  import time
  import traceback
  from datetime import datetime
  from hashlib import md5
  from tempfile import mkstemp
  from urllib import unquote
  from contextlib import contextmanager
  
  from xattr import getxattr, setxattr
  from eventlet import sleep, Timeout, tpool
  
  from swift.common.utils import mkdirs, normalize_timestamp, public, \
      storage_directory, hash_path, renamer, fallocate, fsync, fdatasync, \
      split_path, drop_buffer_cache, get_logger, write_pickle, \
      config_true_value, validate_device_partition, timing_stats
  from swift.common.bufferedhttp import http_connect
  from swift.common.constraints import check_object_creation, check_mount, \
      check_float, check_utf8
  from swift.common.exceptions import ConnectionTimeout, DiskFileError, \
      DiskFileNotExist
  from swift.obj.replicator import tpool_reraise, invalidate_hash, \
      quarantine_renamer, get_hashes
  from swift.common.http import is_success
  from swift.common.swob import HTTPAccepted, HTTPBadRequest, HTTPCreated, \
      HTTPInternalServerError, HTTPNoContent, HTTPNotFound, HTTPNotModified, \
      HTTPPreconditionFailed, HTTPRequestTimeout, HTTPUnprocessableEntity, \
      HTTPClientDisconnect, HTTPMethodNotAllowed, Request, Response, UTC, \
      HTTPInsufficientStorage, multi_range_iterator
  
  
  DATADIR = 'objects'
  ASYNCDIR = 'async_pending'
  PICKLE_PROTOCOL = 2
  METADATA_KEY = 'user.swift.metadata'
  MAX_OBJECT_NAME_LENGTH = 1024
  # keep these lower-case
  DISALLOWED_HEADERS = set('content-length content-type deleted etag'.split())
  
  
  def read_metadata(fd):
      """
      Helper function to read the pickled metadata from an object file.
  
      :param fd: file descriptor to load the metadata from
  
      :returns: dictionary of metadata
      """
      metadata = ''
      key = 0
      try:
          while True:
              metadata += getxattr(fd, '%s%s' % (METADATA_KEY, (key or '')))
              key += 1
      except IOError:
          pass
      return pickle.loads(metadata)
  
  
  def write_metadata(fd, metadata):
      """
      Helper function to write pickled metadata for an object file.
  
      :param fd: file descriptor to write the metadata
      :param metadata: metadata to write
      """
      metastr = pickle.dumps(metadata, PICKLE_PROTOCOL)
      key = 0
      while metastr:
          setxattr(fd, '%s%s' % (METADATA_KEY, key or ''), metastr[:254])
          metastr = metastr[254:]
          key += 1
  
  
  class DiskFile(object):
      """
      Manage object files on disk.
  
      :param path: path to devices on the node
      :param device: device name
      :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 keep_data_fp: if True, don't close the fp, otherwise close it
      :param disk_chunk_size: size of chunks on file reads
      :param iter_hook: called when __iter__ returns a chunk
      """
  
      def __init__(self, path, device, partition, account, container, obj,
                   logger, keep_data_fp=False, disk_chunk_size=65536,
                   iter_hook=None):
          self.disk_chunk_size = disk_chunk_size
          self.iter_hook = iter_hook
          self.name = '/' + '/'.join((account, container, obj))
          name_hash = hash_path(account, container, obj)
          self.datadir = os.path.join(
              path, device, storage_directory(DATADIR, partition, name_hash))
          self.device_path = os.path.join(path, device)
          self.tmpdir = os.path.join(path, device, 'tmp')
          self.tmppath = None
          self.logger = logger
          self.metadata = {}
          self.meta_file = None
          self.data_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.suppress_file_closing = False
          if not os.path.exists(self.datadir):
              return
          files = sorted(os.listdir(self.datadir), reverse=True)
          for file in files:
              if file.endswith('.ts'):
                  self.data_file = self.meta_file = None
                  self.metadata = {'deleted': True}
                  return
              if file.endswith('.meta') and not self.meta_file:
                  self.meta_file = os.path.join(self.datadir, file)
              if file.endswith('.data') and not self.data_file:
                  self.data_file = os.path.join(self.datadir, file)
                  break
          if not self.data_file:
              return
          self.fp = open(self.data_file, 'rb')
          self.metadata = read_metadata(self.fp)
          if not keep_data_fp:
              self.close(verify_file=False)
          if self.meta_file:
              with open(self.meta_file) as mfp:
                  for key in self.metadata.keys():
                      if key.lower() not in DISALLOWED_HEADERS:
                          del self.metadata[key]
                  self.metadata.update(read_metadata(mfp))
  
      def __iter__(self):
          """Returns an iterator over the data file."""
          try:
              dropped_cache = 0
              read = 0
              self.started_at_0 = False
              self.read_to_eof = False
              if self.fp.tell() == 0:
                  self.started_at_0 = True
                  self.iter_etag = md5()
              while True:
                  chunk = self.fp.read(self.disk_chunk_size)
                  if chunk:
                      if self.iter_etag:
                          self.iter_etag.update(chunk)
                      read += len(chunk)
                      if read - dropped_cache > (1024 * 1024):
                          self.drop_cache(self.fp.fileno(), dropped_cache,
                                          read - dropped_cache)
                          dropped_cache = read
                      yield chunk
                      if self.iter_hook:
                          self.iter_hook()
                  else:
                      self.read_to_eof = True
                      self.drop_cache(self.fp.fileno(), dropped_cache,
                                      read - dropped_cache)
                      break
          finally:
              if not self.suppress_file_closing:
                  self.close()
  
      def app_iter_range(self, start, stop):
          """Returns an iterator over the data file for range (start, stop)"""
          if start or start == 0:
              self.fp.seek(start)
          if stop is not None:
              length = stop - start
          else:
              length = None
          for chunk in self:
              if length is not None:
                  length -= len(chunk)
                  if length < 0:
                      # Chop off the extra:
                      yield chunk[:length]
                      break
              yield chunk
  
      def app_iter_ranges(self, ranges, content_type, boundary, size):
          """Returns an iterator over the data file for a set of ranges"""
          if not ranges:
              yield ''
          else:
              try:
                  self.suppress_file_closing = True
                  for chunk in multi_range_iterator(
                          ranges, content_type, boundary, size,
                          self.app_iter_range):
                      yield chunk
              finally:
                  self.suppress_file_closing = False
                  self.close()
  
      def _handle_close_quarantine(self):
          """Check if file needs to be quarantined"""
          try:
              self.get_data_file_size()
          except DiskFileError:
              self.quarantine()
              return
          except DiskFileNotExist:
              return
  
          if self.iter_etag and self.started_at_0 and self.read_to_eof and \
                  'ETag' in self.metadata and \
                  self.iter_etag.hexdigest() != self.metadata.get('ETag'):
              self.quarantine()
  
      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.
          """
          if self.fp:
              try:
                  if verify_file:
                      self._handle_close_quarantine()
              except (Exception, Timeout), e:
                  self.logger.error(_(
                      'ERROR DiskFile %(data_file)s in '
                      '%(data_dir)s close failure: %(exc)s : %(stack)'),
                      {'exc': e, 'stack': ''.join(traceback.format_stack()),
                       'data_file': self.data_file, 'data_dir': self.datadir})
              finally:
                  self.fp.close()
                  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 or 'deleted' in self.metadata
  
      def is_expired(self):
          """
          Check if the file is expired.
  
          :returns: True if the file has an X-Delete-At in the past
          """
          return ('X-Delete-At' in self.metadata and
                  int(self.metadata['X-Delete-At']) <= time.time())
  
      @contextmanager
      def mkstemp(self):
          """Contextmanager to make a temporary file."""
          if not os.path.exists(self.tmpdir):
              mkdirs(self.tmpdir)
          fd, self.tmppath = mkstemp(dir=self.tmpdir)
          try:
              yield fd
          finally:
              try:
                  os.close(fd)
              except OSError:
                  pass
              tmppath, self.tmppath = self.tmppath, None
              try:
                  os.unlink(tmppath)
              except OSError:
                  pass
  
      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
          """
          assert self.tmppath is not None
          metadata['name'] = self.name
          timestamp = normalize_timestamp(metadata['X-Timestamp'])
          write_metadata(fd, metadata)
          if 'Content-Length' in metadata:
              self.drop_cache(fd, 0, int(metadata['Content-Length']))
          tpool.execute(fsync, fd)
          invalidate_hash(os.path.dirname(self.datadir))
          renamer(self.tmppath,
                  os.path.join(self.datadir, timestamp + extension))
          self.metadata = metadata
  
      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
          """
          extension = '.ts' if tombstone else '.meta'
          with self.mkstemp() as fd:
              self.put(fd, metadata, extension=extension)
  
      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
          """
          timestamp = normalize_timestamp(timestamp)
          for fname in os.listdir(self.datadir):
              if fname < timestamp:
                  try:
                      os.unlink(os.path.join(self.datadir, fname))
                  except OSError, err:    # pragma: no cover
                      if err.errno != errno.ENOENT:
                          raise
  
      def drop_cache(self, fd, offset, length):
          """Method for no-oping buffer cache drop method."""
          if not self.keep_cache:
              drop_buffer_cache(fd, offset, length)
  
      def quarantine(self):
          """
          In the case that a file is corrupted, move it to a quarantined
          area to allow replication to fix it.
  
          :returns: if quarantine is successful, path to quarantined
                    directory otherwise None
          """
          if not (self.is_deleted() or self.quarantined_dir):
              self.quarantined_dir = quarantine_renamer(self.device_path,
                                                        self.data_file)
              self.logger.increment('quarantines')
              return self.quarantined_dir
  
      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)
          """
          try:
              file_size = 0
              if self.data_file:
                  file_size = os.path.getsize(self.data_file)
                  if 'Content-Length' in self.metadata:
                      metadata_size = int(self.metadata['Content-Length'])
                      if file_size != metadata_size:
                          raise DiskFileError(
                              'Content-Length of %s does not match file size '
                              'of %s' % (metadata_size, file_size))
                  return file_size
          except OSError, err:
              if err.errno != errno.ENOENT:
                  raise
          raise DiskFileNotExist('Data File does not exist.')
  
  
  class ObjectController(object):
      """Implements the WSGI application for the Swift Object Server."""
  
      def __init__(self, conf):
          """
          Creates a new WSGI application for the Swift Object Server. An
          example configuration is given at
          <source-dir>/etc/object-server.conf-sample or
          /etc/swift/object-server.conf-sample.
          """
          self.logger = get_logger(conf, log_route='object-server')
          self.devices = conf.get('devices', '/srv/node/')
          self.mount_check = config_true_value(conf.get('mount_check', 'true'))
          self.node_timeout = int(conf.get('node_timeout', 3))
          self.conn_timeout = float(conf.get('conn_timeout', 0.5))
          self.disk_chunk_size = int(conf.get('disk_chunk_size', 65536))
          self.network_chunk_size = int(conf.get('network_chunk_size', 65536))
          self.keep_cache_size = int(conf.get('keep_cache_size', 5242880))
          self.keep_cache_private = \
              config_true_value(conf.get('keep_cache_private', 'false'))
          self.log_requests = config_true_value(conf.get('log_requests', 'true'))
          self.max_upload_time = int(conf.get('max_upload_time', 86400))
          self.slow = int(conf.get('slow', 0))
          self.bytes_per_sync = int(conf.get('mb_per_sync', 512)) * 1024 * 1024
          default_allowed_headers = '''
              content-disposition,
              content-encoding,
              x-delete-at,
              x-object-manifest,
              x-static-large-object,
          '''
          self.allowed_headers = set(
              i.strip().lower() for i in
              conf.get('allowed_headers', default_allowed_headers).split(',')
              if i.strip() and i.strip().lower() not in DISALLOWED_HEADERS)
          self.expiring_objects_account = \
              (conf.get('auto_create_account_prefix') or '.') + \
              'expiring_objects'
          self.expiring_objects_container_divisor = \
              int(conf.get('expiring_objects_container_divisor') or 86400)
  
      def async_update(self, op, account, container, obj, host, partition,
                       contdevice, headers_out, objdevice):
          """
          Sends or saves an async update.
  
          :param op: operation performed (ex: 'PUT', or 'DELETE')
          :param account: account name for the object
          :param container: container name for the object
          :param obj: object name
          :param host: host that the container is on
          :param partition: partition that the container is on
          :param contdevice: device name that the container is on
          :param headers_out: dictionary of headers to send in the container
                              request
          :param objdevice: device name that the object is in
          """
          full_path = '/%s/%s/%s' % (account, container, obj)
          if all([host, partition, contdevice]):
              try:
                  with ConnectionTimeout(self.conn_timeout):
                      ip, port = host.rsplit(':', 1)
                      conn = http_connect(ip, port, contdevice, partition, op,
                                          full_path, headers_out)
                  with Timeout(self.node_timeout):
                      response = conn.getresponse()
                      response.read()
                      if is_success(response.status):
                          return
                      else:
                          self.logger.error(_(
                              'ERROR Container update failed '
                              '(saving for async update later): %(status)d '
                              'response from %(ip)s:%(port)s/%(dev)s'),
                              {'status': response.status, 'ip': ip, 'port': port,
                               'dev': contdevice})
              except (Exception, Timeout):
                  self.logger.exception(_(
                      'ERROR container update failed with '
                      '%(ip)s:%(port)s/%(dev)s (saving for async update later)'),
                      {'ip': ip, 'port': port, 'dev': contdevice})
          async_dir = os.path.join(self.devices, objdevice, ASYNCDIR)
          ohash = hash_path(account, container, obj)
          self.logger.increment('async_pendings')
          write_pickle(
              {'op': op, 'account': account, 'container': container,
               'obj': obj, 'headers': headers_out},
              os.path.join(async_dir, ohash[-3:], ohash + '-' +
                           normalize_timestamp(headers_out['x-timestamp'])),
              os.path.join(self.devices, objdevice, 'tmp'))
  
      def container_update(self, op, account, container, obj, headers_in,
                           headers_out, objdevice):
          """
          Update the container when objects are updated.
  
          :param op: operation performed (ex: 'PUT', or 'DELETE')
          :param account: account name for the object
          :param container: container name for the object
          :param obj: object name
          :param headers_in: dictionary of headers from the original request
          :param headers_out: dictionary of headers to send in the container
                              request(s)
          :param objdevice: device name that the object is in
          """
          conthosts = [h.strip() for h in
                       headers_in.get('X-Container-Host', '').split(',')]
          contdevices = [d.strip() for d in
                         headers_in.get('X-Container-Device', '').split(',')]
          contpartition = headers_in.get('X-Container-Partition', '')
  
          if len(conthosts) != len(contdevices):
              # This shouldn't happen unless there's a bug in the proxy,
              # but if there is, we want to know about it.
              self.logger.error(_('ERROR Container update failed: different  '
                                  'numbers of hosts and devices in request: '
                                  '"%s" vs "%s"' %
                                  (headers_in.get('X-Container-Host', ''),
                                   headers_in.get('X-Container-Device', ''))))
              return
  
          if contpartition:
              updates = zip(conthosts, contdevices)
          else:
              updates = []
  
          for conthost, contdevice in updates:
              self.async_update(op, account, container, obj, conthost,
                                contpartition, contdevice, headers_out,
                                objdevice)
  
      def delete_at_update(self, op, delete_at, account, container, obj,
                           headers_in, objdevice):
          """
          Update the expiring objects container when objects are updated.
  
          :param op: operation performed (ex: 'PUT', or 'DELETE')
          :param account: account name for the object
          :param container: container name for the object
          :param obj: object name
          :param headers_in: dictionary of headers from the original request
          :param objdevice: device name that the object is in
          """
          # Quick cap that will work from now until Sat Nov 20 17:46:39 2286
          # At that time, Swift will be so popular and pervasive I will have
          # created income for thousands of future programmers.
          delete_at = max(min(delete_at, 9999999999), 0)
          updates = [(None, None)]
  
          partition = None
          hosts = contdevices = [None]
          headers_out = {'x-timestamp': headers_in['x-timestamp'],
                         'x-trans-id': headers_in.get('x-trans-id', '-')}
          if op != 'DELETE':
              partition = headers_in.get('X-Delete-At-Partition', None)
              hosts = headers_in.get('X-Delete-At-Host', '')
              contdevices = headers_in.get('X-Delete-At-Device', '')
              updates = [upd for upd in
                         zip((h.strip() for h in hosts.split(',')),
                             (c.strip() for c in contdevices.split(',')))
                         if all(upd) and partition]
              if not updates:
                  updates = [(None, None)]
              headers_out['x-size'] = '0'
              headers_out['x-content-type'] = 'text/plain'
              headers_out['x-etag'] = 'd41d8cd98f00b204e9800998ecf8427e'
  
          for host, contdevice in updates:
              self.async_update(
                  op, self.expiring_objects_account,
                  str(delete_at / self.expiring_objects_container_divisor *
                      self.expiring_objects_container_divisor),
                  '%s-%s/%s/%s' % (delete_at, account, container, obj),
                  host, partition, contdevice, headers_out, objdevice)
  
      @public
      @timing_stats()
      def POST(self, request):
          """Handle HTTP POST requests for the Swift Object Server."""
          try:
              device, partition, account, container, obj = \
                  split_path(unquote(request.path), 5, 5, True)
              validate_device_partition(device, partition)
          except ValueError, err:
              return HTTPBadRequest(body=str(err), request=request,
                                    content_type='text/plain')
          if 'x-timestamp' not in request.headers or \
                  not check_float(request.headers['x-timestamp']):
              return HTTPBadRequest(body='Missing timestamp', request=request,
                                    content_type='text/plain')
          new_delete_at = int(request.headers.get('X-Delete-At') or 0)
          if new_delete_at and new_delete_at < time.time():
              return HTTPBadRequest(body='X-Delete-At in past', request=request,
                                    content_type='text/plain')
          if self.mount_check and not check_mount(self.devices, device):
              return HTTPInsufficientStorage(drive=device, request=request)
          file = DiskFile(self.devices, device, partition, account, container,
                          obj, self.logger, disk_chunk_size=self.disk_chunk_size)
  
          if file.is_deleted() or file.is_expired():
              return HTTPNotFound(request=request)
          try:
              file.get_data_file_size()
          except (DiskFileError, DiskFileNotExist):
              file.quarantine()
              return HTTPNotFound(request=request)
          metadata = {'X-Timestamp': request.headers['x-timestamp']}
          metadata.update(val for val in request.headers.iteritems()
                          if val[0].lower().startswith('x-object-meta-'))
          for header_key in self.allowed_headers:
              if header_key in request.headers:
                  header_caps = header_key.title()
                  metadata[header_caps] = request.headers[header_key]
          old_delete_at = int(file.metadata.get('X-Delete-At') or 0)
          if old_delete_at != new_delete_at:
              if new_delete_at:
                  self.delete_at_update('PUT', new_delete_at, account, container,
                                        obj, request.headers, device)
              if old_delete_at:
                  self.delete_at_update('DELETE', old_delete_at, account,
                                        container, obj, request.headers, device)
          file.put_metadata(metadata)
          return HTTPAccepted(request=request)
  
      @public
      @timing_stats()
      def PUT(self, request):
          """Handle HTTP PUT requests for the Swift Object Server."""
          try:
              device, partition, account, container, obj = \
                  split_path(unquote(request.path), 5, 5, True)
              validate_device_partition(device, partition)
          except ValueError, err:
              return HTTPBadRequest(body=str(err), request=request,
                                    content_type='text/plain')
          if self.mount_check and not check_mount(self.devices, device):
              return HTTPInsufficientStorage(drive=device, request=request)
          if 'x-timestamp' not in request.headers or \
                  not check_float(request.headers['x-timestamp']):
              return HTTPBadRequest(body='Missing timestamp', request=request,
                                    content_type='text/plain')
          error_response = check_object_creation(request, obj)
          if error_response:
              return error_response
          new_delete_at = int(request.headers.get('X-Delete-At') or 0)
          if new_delete_at and new_delete_at < time.time():
              return HTTPBadRequest(body='X-Delete-At in past', request=request,
                                    content_type='text/plain')
          file = DiskFile(self.devices, device, partition, account, container,
                          obj, self.logger, disk_chunk_size=self.disk_chunk_size)
          orig_timestamp = file.metadata.get('X-Timestamp')
          upload_expiration = time.time() + self.max_upload_time
          etag = md5()
          upload_size = 0
          last_sync = 0
          elasped_time = 0
          with file.mkstemp() as fd:
              try:
                  fallocate(fd, int(request.headers.get('content-length', 0)))
              except OSError:
                  return HTTPInsufficientStorage(drive=device, request=request)
              reader = request.environ['wsgi.input'].read
              for chunk in iter(lambda: reader(self.network_chunk_size), ''):
                  start_time = time.time()
                  upload_size += len(chunk)
                  if time.time() > upload_expiration:
                      self.logger.increment('PUT.timeouts')
                      return HTTPRequestTimeout(request=request)
                  etag.update(chunk)
                  while chunk:
                      written = os.write(fd, chunk)
                      chunk = chunk[written:]
                  # For large files sync every 512MB (by default) written
                  if upload_size - last_sync >= self.bytes_per_sync:
                      tpool.execute(fdatasync, fd)
                      drop_buffer_cache(fd, last_sync, upload_size - last_sync)
                      last_sync = upload_size
                  sleep()
                  elasped_time += time.time() - start_time
  
              if upload_size:
                  self.logger.transfer_rate(
                      'PUT.' + device + '.timing', elasped_time, upload_size)
  
              if 'content-length' in request.headers and \
                      int(request.headers['content-length']) != upload_size:
                  return HTTPClientDisconnect(request=request)
              etag = etag.hexdigest()
              if 'etag' in request.headers and \
                      request.headers['etag'].lower() != etag:
                  return HTTPUnprocessableEntity(request=request)
              metadata = {
                  'X-Timestamp': request.headers['x-timestamp'],
                  'Content-Type': request.headers['content-type'],
                  'ETag': etag,
                  'Content-Length': str(upload_size),
              }
              metadata.update(val for val in request.headers.iteritems()
                              if val[0].lower().startswith('x-object-meta-') and
                              len(val[0]) > 14)
              for header_key in self.allowed_headers:
                  if header_key in request.headers:
                      header_caps = header_key.title()
                      metadata[header_caps] = request.headers[header_key]
              old_delete_at = int(file.metadata.get('X-Delete-At') or 0)
              if old_delete_at != new_delete_at:
                  if new_delete_at:
                      self.delete_at_update(
                          'PUT', new_delete_at, account, container, obj,
                          request.headers, device)
                  if old_delete_at:
                      self.delete_at_update(
                          'DELETE', old_delete_at, account, container, obj,
                          request.headers, device)
              file.put(fd, metadata)
          file.unlinkold(metadata['X-Timestamp'])
          if not orig_timestamp or \
                  orig_timestamp < request.headers['x-timestamp']:
              self.container_update(
                  'PUT', account, container, obj, request.headers,
                  {'x-size': file.metadata['Content-Length'],
                   'x-content-type': file.metadata['Content-Type'],
                   'x-timestamp': file.metadata['X-Timestamp'],
                   'x-etag': file.metadata['ETag'],
                   'x-trans-id': request.headers.get('x-trans-id', '-')},
                  device)
          resp = HTTPCreated(request=request, etag=etag)
          return resp
  
      @public
      @timing_stats()
      def GET(self, request):
          """Handle HTTP GET requests for the Swift Object Server."""
          try:
              device, partition, account, container, obj = \
                  split_path(unquote(request.path), 5, 5, True)
              validate_device_partition(device, partition)
          except ValueError, err:
              return HTTPBadRequest(body=str(err), request=request,
                                    content_type='text/plain')
          if self.mount_check and not check_mount(self.devices, device):
              return HTTPInsufficientStorage(drive=device, request=request)
          file = DiskFile(self.devices, device, partition, account, container,
                          obj, self.logger, keep_data_fp=True,
                          disk_chunk_size=self.disk_chunk_size,
                          iter_hook=sleep)
          if file.is_deleted() or file.is_expired():
              if request.headers.get('if-match') == '*':
                  return HTTPPreconditionFailed(request=request)
              else:
                  return HTTPNotFound(request=request)
          try:
              file_size = file.get_data_file_size()
          except (DiskFileError, DiskFileNotExist):
              file.quarantine()
              return HTTPNotFound(request=request)
          if request.headers.get('if-match') not in (None, '*') and \
                  file.metadata['ETag'] not in request.if_match:
              file.close()
              return HTTPPreconditionFailed(request=request)
          if request.headers.get('if-none-match') is not None:
              if file.metadata['ETag'] in request.if_none_match:
                  resp = HTTPNotModified(request=request)
                  resp.etag = file.metadata['ETag']
                  file.close()
                  return resp
          try:
              if_unmodified_since = request.if_unmodified_since
          except (OverflowError, ValueError):
              # catches timestamps before the epoch
              return HTTPPreconditionFailed(request=request)
          if if_unmodified_since and \
                  datetime.fromtimestamp(
                      float(file.metadata['X-Timestamp']), UTC) > \
                  if_unmodified_since:
              file.close()
              return HTTPPreconditionFailed(request=request)
          try:
              if_modified_since = request.if_modified_since
          except (OverflowError, ValueError):
              # catches timestamps before the epoch
              return HTTPPreconditionFailed(request=request)
          if if_modified_since and \
                  datetime.fromtimestamp(
                      float(file.metadata['X-Timestamp']), UTC) < \
                  if_modified_since:
              file.close()
              return HTTPNotModified(request=request)
          response = Response(app_iter=file,
                              request=request, conditional_response=True)
          response.headers['Content-Type'] = file.metadata.get(
              'Content-Type', 'application/octet-stream')
          for key, value in file.metadata.iteritems():
              if key.lower().startswith('x-object-meta-') or \
                      key.lower() in self.allowed_headers:
                  response.headers[key] = value
          response.etag = file.metadata['ETag']
          response.last_modified = float(file.metadata['X-Timestamp'])
          response.content_length = file_size
          if response.content_length < self.keep_cache_size and \
                  (self.keep_cache_private or
                   ('X-Auth-Token' not in request.headers and
                    'X-Storage-Token' not in request.headers)):
              file.keep_cache = True
          if 'Content-Encoding' in file.metadata:
              response.content_encoding = file.metadata['Content-Encoding']
          response.headers['X-Timestamp'] = file.metadata['X-Timestamp']
          return request.get_response(response)
  
      @public
      @timing_stats(sample_rate=0.8)
      def HEAD(self, request):
          """Handle HTTP HEAD requests for the Swift Object Server."""
          try:
              device, partition, account, container, obj = \
                  split_path(unquote(request.path), 5, 5, True)
              validate_device_partition(device, partition)
          except ValueError, err:
              resp = HTTPBadRequest(request=request)
              resp.content_type = 'text/plain'
              resp.body = str(err)
              return resp
          if self.mount_check and not check_mount(self.devices, device):
              return HTTPInsufficientStorage(drive=device, request=request)
          file = DiskFile(self.devices, device, partition, account, container,
                          obj, self.logger, disk_chunk_size=self.disk_chunk_size)
          if file.is_deleted() or file.is_expired():
              return HTTPNotFound(request=request)
          try:
              file_size = file.get_data_file_size()
          except (DiskFileError, DiskFileNotExist):
              file.quarantine()
              return HTTPNotFound(request=request)
          response = Response(request=request, conditional_response=True)
          response.headers['Content-Type'] = file.metadata.get(
              'Content-Type', 'application/octet-stream')
          for key, value in file.metadata.iteritems():
              if key.lower().startswith('x-object-meta-') or \
                      key.lower() in self.allowed_headers:
                  response.headers[key] = value
          response.etag = file.metadata['ETag']
          response.last_modified = float(file.metadata['X-Timestamp'])
          # Needed for container sync feature
          response.headers['X-Timestamp'] = file.metadata['X-Timestamp']
          response.content_length = file_size
          if 'Content-Encoding' in file.metadata:
              response.content_encoding = file.metadata['Content-Encoding']
          return response
  
      @public
      @timing_stats()
      def DELETE(self, request):
          """Handle HTTP DELETE requests for the Swift Object Server."""
          try:
              device, partition, account, container, obj = \
                  split_path(unquote(request.path), 5, 5, True)
              validate_device_partition(device, partition)
          except ValueError, e:
              return HTTPBadRequest(body=str(e), request=request,
                                    content_type='text/plain')
          if 'x-timestamp' not in request.headers or \
                  not check_float(request.headers['x-timestamp']):
              return HTTPBadRequest(body='Missing timestamp', request=request,
                                    content_type='text/plain')
          if self.mount_check and not check_mount(self.devices, device):
              return HTTPInsufficientStorage(drive=device, request=request)
          response_class = HTTPNoContent
          file = DiskFile(self.devices, device, partition, account, container,
                          obj, self.logger, disk_chunk_size=self.disk_chunk_size)
          if 'x-if-delete-at' in request.headers and \
                  int(request.headers['x-if-delete-at']) != \
                  int(file.metadata.get('X-Delete-At') or 0):
              return HTTPPreconditionFailed(
                  request=request,
                  body='X-If-Delete-At and X-Delete-At do not match')
          orig_timestamp = file.metadata.get('X-Timestamp')
          if file.is_deleted() or file.is_expired():
              response_class = HTTPNotFound
          metadata = {
              'X-Timestamp': request.headers['X-Timestamp'], 'deleted': True,
          }
          old_delete_at = int(file.metadata.get('X-Delete-At') or 0)
          if old_delete_at:
              self.delete_at_update('DELETE', old_delete_at, account,
                                    container, obj, request.headers, device)
          file.put_metadata(metadata, tombstone=True)
          file.unlinkold(metadata['X-Timestamp'])
          if not orig_timestamp or \
                  orig_timestamp < request.headers['x-timestamp']:
              self.container_update(
                  'DELETE', account, container, obj, request.headers,
                  {'x-timestamp': metadata['X-Timestamp'],
                   'x-trans-id': request.headers.get('x-trans-id', '-')},
                  device)
          resp = response_class(request=request)
          return resp
  
      @public
      @timing_stats(sample_rate=0.1)
      def REPLICATE(self, request):
          """
          Handle REPLICATE requests for the Swift Object Server.  This is used
          by the object replicator to get hashes for directories.
          """
          try:
              device, partition, suffix = split_path(
                  unquote(request.path), 2, 3, True)
              validate_device_partition(device, partition)
          except ValueError, e:
              return HTTPBadRequest(body=str(e), request=request,
                                    content_type='text/plain')
          if self.mount_check and not check_mount(self.devices, device):
              return HTTPInsufficientStorage(drive=device, request=request)
          path = os.path.join(self.devices, device, DATADIR, partition)
          if not os.path.exists(path):
              mkdirs(path)
          suffixes = suffix.split('-') if suffix else []
          _junk, hashes = tpool_reraise(get_hashes, path, recalculate=suffixes)
          return Response(body=pickle.dumps(hashes))
  
      def __call__(self, env, start_response):
          """WSGI Application entry point for the Swift Object Server."""
          start_time = time.time()
          req = Request(env)
          self.logger.txn_id = req.headers.get('x-trans-id', None)
  
          if not check_utf8(req.path_info):
              res = HTTPPreconditionFailed(body='Invalid UTF8 or contains NULL')
          else:
              try:
                  # disallow methods which have not been marked 'public'
                  try:
                      method = getattr(self, req.method)
                      getattr(method, 'publicly_accessible')
                  except AttributeError:
                      res = HTTPMethodNotAllowed()
                  else:
                      res = method(req)
              except (Exception, Timeout):
                  self.logger.exception(_(
                      'ERROR __call__ error with %(method)s'
                      ' %(path)s '), {'method': req.method, 'path': req.path})
                  res = HTTPInternalServerError(body=traceback.format_exc())
          trans_time = time.time() - start_time
          if self.log_requests:
              log_line = '%s - - [%s] "%s %s" %s %s "%s" "%s" "%s" %.4f' % (
                  req.remote_addr,
                  time.strftime('%d/%b/%Y:%H:%M:%S +0000',
                                time.gmtime()),
                  req.method, req.path, res.status.split()[0],
                  res.content_length or '-', req.referer or '-',
                  req.headers.get('x-trans-id', '-'),
                  req.user_agent or '-',
                  trans_time)
              if req.method == 'REPLICATE':
                  self.logger.debug(log_line)
              else:
                  self.logger.info(log_line)
          if req.method in ('PUT', 'DELETE'):
              slow = self.slow - trans_time
              if slow > 0:
                  sleep(slow)
          return res(env, start_response)
  
  
  def app_factory(global_conf, **local_conf):
      """paste.deploy app factory for creating WSGI object server apps"""
      conf = global_conf.copy()
      conf.update(local_conf)
      return ObjectController(conf)
  