[Zodb-checkins] SVN: ZODB/branches/ctheune-bushy-directory/src/
merge from current trunk
Christian Theune
ct at gocept.com
Mon Aug 4 14:39:18 EDT 2008
Log message for revision 89351:
merge from current trunk
Changed:
U ZODB/branches/ctheune-bushy-directory/src/BTrees/Interfaces.py
U ZODB/branches/ctheune-bushy-directory/src/CHANGES.txt
U ZODB/branches/ctheune-bushy-directory/src/ZEO/ClientStorage.py
U ZODB/branches/ctheune-bushy-directory/src/ZEO/tests/testZEO.py
U ZODB/branches/ctheune-bushy-directory/src/ZODB/blob.py
D ZODB/branches/ctheune-bushy-directory/src/ZODB/scripts/migrateblobs.py
D ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_layout.txt
U ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_packing.txt
U ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_tempdir.txt
U ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_transaction.txt
U ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/testblob.py
-=-
Modified: ZODB/branches/ctheune-bushy-directory/src/BTrees/Interfaces.py
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/BTrees/Interfaces.py 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/BTrees/Interfaces.py 2008-08-04 18:39:18 UTC (rev 89351)
@@ -140,13 +140,19 @@
Return the default if has_key(key) is false.
"""
+ def __getitem__(key):
+ """Get the value associated with the given key.
+
+ Raise KeyError if has_key(key) is false.
+ """
+
def __setitem__(key, value):
"""Set the value associated with the given key."""
def __delitem__(key):
"""Delete the value associated with the given key.
- Raise KeyError if the key if has_key(key) is false.
+ Raise KeyError if has_key(key) is false.
"""
def values(min=None, max=None, excludemin=False, excludemax=False):
Modified: ZODB/branches/ctheune-bushy-directory/src/CHANGES.txt
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/CHANGES.txt 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/CHANGES.txt 2008-08-04 18:39:18 UTC (rev 89351)
@@ -8,12 +8,6 @@
New Features
------------
-- Changed layout strategy for the blob directory to a bushy approach (8 levels
- deep, at most ~256 entries per directory level, one directory for each
- blob). Old directories are automatically detected and will be handled with
- the old strategy. A migration script (`migrateblobs.py`) is provided to
- convert the different layouts.
-
- Versions are no-longer supported.
- ZEO cache files can be larger than 4G. Note that older ZEO cache
@@ -43,8 +37,10 @@
Bugs Fixed
----------
-- Fix for bug# 220856: Completed implementation of ZEO authentication.
+- Fix for bug #251037: Make packing of blob storages non-blocking.
+- Fix for bug #220856: Completed implementation of ZEO authentication.
+
- Fix for bug #184057: Make initialisation of small ZEO client file cache
sizes not fail.
Modified: ZODB/branches/ctheune-bushy-directory/src/ZEO/ClientStorage.py
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZEO/ClientStorage.py 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZEO/ClientStorage.py 2008-08-04 18:39:18 UTC (rev 89351)
@@ -855,7 +855,9 @@
def _storeBlob_shared(self, oid, serial, data, filename, txn):
# First, move the blob into the blob directory
- self.fshelper.getPathForOID(oid, create=True)
+ dir = self.fshelper.getPathForOID(oid)
+ if not os.path.exists(dir):
+ os.mkdir(dir)
fd, target = self.fshelper.blob_mkstemp(oid, serial)
os.close(fd)
@@ -922,7 +924,14 @@
raise POSException.POSKeyError("No blob file", oid, serial)
# First, we'll create the directory for this oid, if it doesn't exist.
- targetpath = self.fshelper.getPathForOID(oid, create=True)
+ targetpath = self.fshelper.getPathForOID(oid)
+ if not os.path.exists(targetpath):
+ try:
+ os.makedirs(targetpath, 0700)
+ except OSError:
+ # We might have lost a race. If so, the directory
+ # must exist now
+ assert os.path.exists(targetpath)
# OK, it's not here and we (or someone) needs to get it. We
# want to avoid getting it multiple times. We want to avoid
@@ -1109,15 +1118,19 @@
assert s == tid, (s, tid)
self._cache.store(oid, s, None, data)
+
if self.fshelper is not None:
blobs = self._tbuf.blobs
while blobs:
oid, blobfilename = blobs.pop()
- targetpath = self.fshelper.getPathForOID(oid, create=True)
+ targetpath = self.fshelper.getPathForOID(oid)
+ if not os.path.exists(targetpath):
+ os.makedirs(targetpath, 0700)
rename_or_copy_blob(blobfilename,
self.fshelper.getBlobFilename(oid, tid),
)
+
self._tbuf.clear()
def undo(self, trans_id, txn):
Modified: ZODB/branches/ctheune-bushy-directory/src/ZEO/tests/testZEO.py
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZEO/tests/testZEO.py 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZEO/tests/testZEO.py 2008-08-04 18:39:18 UTC (rev 89351)
@@ -515,7 +515,8 @@
self._storage.tpc_abort(t)
raise
self.assert_(not os.path.exists(tfname))
- filename = self._storage.fshelper.getBlobFilename(oid, revid)
+ filename = os.path.join(self.blobdir, oid_repr(oid),
+ tid_repr(revid) + BLOB_SUFFIX)
self.assert_(os.path.exists(filename))
self.assertEqual(somedata, open(filename).read())
@@ -629,16 +630,18 @@
d1 = f.read(8096)
d2 = somedata.read(8096)
self.assertEqual(d1, d2)
+
+
+ # The file should have been copied to the server:
+ filename = os.path.join(self.blobdir, oid_repr(oid),
+ tid_repr(revid) + BLOB_SUFFIX)
+ check_data(filename)
- # The file should be in the cache ...
- filename = self._storage.fshelper.getBlobFilename(oid, revid)
+ # It should also be in the cache:
+ filename = os.path.join(self.blob_cache_dir, oid_repr(oid),
+ tid_repr(revid) + BLOB_SUFFIX)
check_data(filename)
- # ... and on the server
- server_filename = filename.replace(self.blob_cache_dir, self.blobdir)
- self.assert_(server_filename.startswith(self.blobdir))
- check_data(server_filename)
-
# If we remove it from the cache and call loadBlob, it should
# come back. We can do this in many threads. We'll instrument
# the method that is used to request data from teh server to
Modified: ZODB/branches/ctheune-bushy-directory/src/ZODB/blob.py
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/blob.py 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/blob.py 2008-08-04 18:39:18 UTC (rev 89351)
@@ -15,10 +15,8 @@
"""
import base64
-import binascii
import logging
import os
-import re
import shutil
import stat
import sys
@@ -45,9 +43,6 @@
BLOB_SUFFIX = ".blob"
SAVEPOINT_SUFFIX = ".spb"
-LAYOUT_MARKER = '.layout'
-LAYOUTS = {}
-
valid_modes = 'r', 'w', 'r+', 'a'
# Threading issues:
@@ -297,43 +292,22 @@
# with blobs and storages needn't indirect through this if they
# want to perform blob storage differently.
- def __init__(self, base_dir, layout_name='automatic'):
- self.base_dir = os.path.normpath(base_dir) + '/'
+ def __init__(self, base_dir):
+ self.base_dir = base_dir
self.temp_dir = os.path.join(base_dir, 'tmp')
- if layout_name == 'automatic':
- layout_name = auto_layout_select(base_dir)
- if layout_name == 'lawn':
- log('The `lawn` blob directory layout is deprecated due to '
- 'scalability issues on some file systems, please consider '
- 'migrating to the `bushy` layout.', level=logging.WARN)
- self.layout_name = layout_name
- self.layout = LAYOUTS[layout_name]
-
def create(self):
if not os.path.exists(self.base_dir):
os.makedirs(self.base_dir, 0700)
- log("Blob directory '%s' does not exist. "
- "Created new directory." % self.base_dir)
+ log("Blob cache directory '%s' does not exist. "
+ "Created new directory." % self.base_dir,
+ level=logging.INFO)
if not os.path.exists(self.temp_dir):
os.makedirs(self.temp_dir, 0700)
log("Blob temporary directory '%s' does not exist. "
- "Created new directory." % self.temp_dir)
+ "Created new directory." % self.temp_dir,
+ level=logging.INFO)
- if not os.path.exists(os.path.join(self.base_dir, LAYOUT_MARKER)):
- layout_marker = open(
- os.path.join(self.base_dir, LAYOUT_MARKER), 'wb')
- layout_marker.write(self.layout_name)
- else:
- layout_marker = open(
- os.path.join(self.base_dir, LAYOUT_MARKER), 'rb')
- layout = layout_marker.read().strip()
- if layout != self.layout_name:
- raise ValueError(
- "Directory layout `%s` selected for blob directory %s, but "
- "marker found for layout `%s`" %
- (self.layout_name, self.base_dir, layout))
-
def isSecure(self, path):
"""Ensure that (POSIX) path mode bits are 0700."""
return (os.stat(path).st_mode & 077) == 0
@@ -343,51 +317,19 @@
log('Blob dir %s has insecure mode setting' % self.base_dir,
level=logging.WARNING)
- def getPathForOID(self, oid, create=False):
+ def getPathForOID(self, oid):
"""Given an OID, return the path on the filesystem where
the blob data relating to that OID is stored.
- If the create flag is given, the path is also created if it didn't
- exist already.
-
"""
- # OIDs are numbers and sometimes passed around as integers. For our
- # computations we rely on the 64-bit packed string representation.
- if isinstance(oid, int):
- oid = utils.p64(oid)
+ return os.path.join(self.base_dir, utils.oid_repr(oid))
- path = self.layout.oid_to_path(oid)
- path = os.path.join(self.base_dir, path)
-
- if create and not os.path.exists(path):
- try:
- os.makedirs(path, 0700)
- except OSError:
- # We might have lost a race. If so, the directory
- # must exist now
- assert os.path.exists(targetpath)
- return path
-
- def getOIDForPath(self, path):
- """Given a path, return an OID, if the path is a valid path for an
- OID. The inverse function to `getPathForOID`.
-
- Raises ValueError if the path is not valid for an OID.
-
- """
- path = path[len(self.base_dir):]
- return self.layout.path_to_oid(path)
-
def getBlobFilename(self, oid, tid):
"""Given an oid and a tid, return the full filename of the
'committed' blob file related to that oid and tid.
"""
oid_path = self.getPathForOID(oid)
- # TIDs are numbers and sometimes passed around as integers. For our
- # computations we rely on the 64-bit packed string representation
- if isinstance(tid, int):
- tid = utils.p64(tid)
filename = "%s%s" % (utils.tid_repr(tid), BLOB_SUFFIX)
return os.path.join(oid_path, filename)
@@ -417,9 +359,10 @@
if not filename.endswith(BLOB_SUFFIX):
return None, None
path, filename = os.path.split(filename)
- oid = self.getOIDForPath(path)
+ oid = os.path.split(path)[1]
serial = filename[:-len(BLOB_SUFFIX)]
+ oid = utils.repr_to_oid(oid)
serial = utils.repr_to_oid(serial)
return oid, serial
@@ -429,107 +372,30 @@
"""
oids = []
- for oid, oidpath in self.listOIDs():
- for filename in os.listdir(oidpath):
- blob_path = os.path.join(oidpath, filename)
+ base_dir = self.base_dir
+ for oidpath in os.listdir(base_dir):
+ for filename in os.listdir(os.path.join(base_dir, oidpath)):
+ blob_path = os.path.join(base_dir, oidpath, filename)
oid, serial = self.splitBlobFilename(blob_path)
if search_serial == serial:
oids.append(oid)
return oids
def listOIDs(self):
- """Iterates over all paths under the base directory that contain blob
- files.
+ """Lists all OIDs and their paths.
+
"""
- for path, dirs, files in os.walk(self.base_dir):
- try:
- oid = self.getOIDForPath(path)
- except ValueError:
+ for candidate in os.listdir(self.base_dir):
+ if candidate == 'tmp':
continue
- yield oid, path
+ oid = utils.repr_to_oid(candidate)
+ yield oid, self.getPathForOID(oid)
-def auto_layout_select(path):
- # A heuristic to look at a path and determine which directory layout to
- # use.
- layout_marker = os.path.join(path, LAYOUT_MARKER)
- if not os.path.exists(path):
- log('Blob directory %s does not exist. '
- 'Selected `bushy` layout. ' % path)
- layout = 'bushy'
- elif len(os.listdir(path)) == 0:
- log('Blob directory `%s` is unused and has no layout marker set. '
- 'Selected `bushy` layout. ' % path)
- layout = 'bushy'
- elif LAYOUT_MARKER not in os.listdir(path):
- log('Blob directory `%s` is used but has no layout marker set. '
- 'Selected `lawn` layout. ' % path)
- layout = 'lawn'
- else:
- layout = open(layout_marker, 'rb').read()
- layout = layout.strip()
- log('Blob directory `%s` has layout marker set. '
- 'Selected `%s` layout. ' % (path, layout))
- return layout
+class BlobStorageError(Exception):
+ """The blob storage encountered an invalid state."""
-class BushyLayout(object):
- """A bushy directory layout for blob directories.
-
- Creates an 8-level directory structure (one level per byte) in
- little-endian order from the OID of an object.
-
- """
-
- blob_path_pattern = r'^' + (r'0x[0-9a-f]{1,2}/*'*8) + r'$'
- blob_path_pattern = re.compile(blob_path_pattern)
-
- def oid_to_path(self, oid):
- directories = []
- # Create the bushy directory structure with the least significant byte
- # first
- for byte in reversed(str(oid)):
- directories.append('0x%s' % binascii.hexlify(byte))
- return '/'.join(directories)
-
- def path_to_oid(self, path):
- if self.blob_path_pattern.match(path) is None:
- raise ValueError("Not a valid OID path: `%s`" % path)
- path = path.split('/')
- # The path contains the OID in little endian form but the OID itself
- # is big endian.
- path.reverse()
- # Each path segment stores a byte in hex representation. Turn it into
- # an int and then get the character for our byte string.
- oid = ''.join(binascii.unhexlify(byte[2:]) for byte in path)
- return oid
-
-LAYOUTS['bushy'] = BushyLayout()
-
-
-class LawnLayout(object):
- """A shallow directory layout for blob directories.
-
- Creates a single level of directories (one for each oid).
-
- """
-
- def oid_to_path(self, oid):
- return utils.oid_repr(oid)
-
- def path_to_oid(self, path):
- try:
- if path == '':
- # This is a special case where repr_to_oid converts '' to the
- # OID z64.
- raise TypeError()
- return utils.repr_to_oid(path)
- except TypeError:
- raise ValueError('Not a valid OID path: `%s`' % path)
-
-LAYOUTS['lawn'] = LawnLayout()
-
-
class BlobStorage(SpecificationDecoratorBase):
"""A storage to support blobs."""
@@ -537,15 +403,16 @@
# Proxies can't have a __dict__ so specifying __slots__ here allows
# us to have instance attributes explicitly on the proxy.
- __slots__ = ('fshelper', 'dirty_oids', '_BlobStorage__supportsUndo')
+ __slots__ = ('fshelper', 'dirty_oids', '_BlobStorage__supportsUndo',
+ '_blobs_pack_is_in_progress', )
- def __new__(self, base_directory, storage, layout='automatic'):
+ def __new__(self, base_directory, storage):
return SpecificationDecoratorBase.__new__(self, storage)
- def __init__(self, base_directory, storage, layout='automatic'):
+ def __init__(self, base_directory, storage):
# XXX Log warning if storage is ClientStorage
SpecificationDecoratorBase.__init__(self, storage)
- self.fshelper = FilesystemHelper(base_directory, layout)
+ self.fshelper = FilesystemHelper(base_directory)
self.fshelper.create()
self.fshelper.checkSecure()
self.dirty_oids = []
@@ -556,6 +423,7 @@
else:
supportsUndo = supportsUndo()
self.__supportsUndo = supportsUndo
+ self._blobs_pack_is_in_progress = False
@non_overridable
def temporaryDirectory(self):
@@ -576,7 +444,10 @@
self._lock_acquire()
try:
- self.fshelper.getPathForOID(oid, create=True)
+ targetpath = self.fshelper.getPathForOID(oid)
+ if not os.path.exists(targetpath):
+ os.makedirs(targetpath, 0700)
+
targetname = self.fshelper.getBlobFilename(oid, serial)
rename_or_copy_blob(blobfilename, targetname)
@@ -622,12 +493,14 @@
# if they are still needed by attempting to load the revision
# of that object from the database. This is maybe the slowest
# possible way to do this, but it's safe.
+ base_dir = self.fshelper.base_dir
for oid, oid_path in self.fshelper.listOIDs():
files = os.listdir(oid_path)
for filename in files:
filepath = os.path.join(oid_path, filename)
whatever, serial = self.fshelper.splitBlobFilename(filepath)
try:
+ fn = self.fshelper.getBlobFilename(oid, serial)
self.loadSerial(oid, serial)
except POSKeyError:
remove_committed(filepath)
@@ -637,6 +510,7 @@
@non_overridable
def _packNonUndoing(self, packtime, referencesf):
+ base_dir = self.fshelper.base_dir
for oid, oid_path in self.fshelper.listOIDs():
exists = True
try:
@@ -660,21 +534,29 @@
@non_overridable
def pack(self, packtime, referencesf):
- """Remove all unused oid/tid combinations."""
- unproxied = getProxiedObject(self)
-
- # pack the underlying storage, which will allow us to determine
- # which serials are current.
- result = unproxied.pack(packtime, referencesf)
-
- # perform a pack on blob data
+ """Remove all unused OID/TID combinations."""
self._lock_acquire()
try:
+ if self._blobs_pack_is_in_progress:
+ raise BlobStorageError('Already packing')
+ self._blobs_pack_is_in_progress = True
+ finally:
+ self._lock_release()
+
+ try:
+ # Pack the underlying storage, which will allow us to determine
+ # which serials are current.
+ unproxied = getProxiedObject(self)
+ result = unproxied.pack(packtime, referencesf)
+
+ # Perform a pack on the blob data.
if self.__supportsUndo:
self._packUndoing(packtime, referencesf)
else:
self._packNonUndoing(packtime, referencesf)
finally:
+ self._lock_acquire()
+ self._blobs_pack_is_in_progress = False
self._lock_release()
return result
@@ -704,6 +586,7 @@
# we get all the blob oids on the filesystem related to the
# transaction we want to undo.
for oid in self.fshelper.getOIDsForSerial(serial_id):
+
# we want to find the serial id of the previous revision
# of this blob object.
load_result = self.loadBefore(oid, serial_id)
Deleted: ZODB/branches/ctheune-bushy-directory/src/ZODB/scripts/migrateblobs.py
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/scripts/migrateblobs.py 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/scripts/migrateblobs.py 2008-08-04 18:39:18 UTC (rev 89351)
@@ -1,74 +0,0 @@
-##############################################################################
-#
-# Copyright (c) 2008 Zope Corporation and Contributors.
-# All Rights Reserved.
-#
-# This software is subject to the provisions of the Zope Public License,
-# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
-# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
-# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
-# FOR A PARTICULAR PURPOSE
-#
-##############################################################################
-"""A script to migrate a blob directory into a different layout.
-"""
-
-import logging
-import optparse
-import os
-
-from ZODB.blob import FilesystemHelper, rename_or_copy_blob
-from ZODB.utils import cp, oid_repr
-
-
-def link_or_copy(f1, f2):
- try:
- os.link(f1, f2)
- except OSError:
- shutil.copy(f1, f2)
-
-
-def migrate(source, dest, layout):
- source_fsh = FilesystemHelper(source)
- source_fsh.create()
- dest_fsh = FilesystemHelper(dest, layout)
- dest_fsh.create()
- print "Migrating blob data from `%s` (%s) to `%s` (%s)" % (
- source, source_fsh.layout_name, dest, dest_fsh.layout_name)
- for oid, path in source_fsh.listOIDs():
- dest_path = dest_fsh.getPathForOID(oid, create=True)
- files = os.listdir(path)
- for file in files:
- source_file = os.path.join(path, file)
- dest_file = os.path.join(dest_path, file)
- link_or_copy(source_file, dest_file)
- print "\tOID: %s - %s files " % (oid_repr(oid), len(files))
-
-
-def main(source=None, dest=None, layout="bushy"):
- usage = "usage: %prog [options] <source> <dest> <layout>"
- description = ("Create the new directory <dest> and migrate all blob "
- "data <source> to <dest> while using the new <layout> for "
- "<dest>")
-
- parser = optparse.OptionParser(usage=usage, description=description)
- parser.add_option("-l", "--layout",
- default=layout, type='choice',
- choices=['bushy', 'lawn'],
- help="Define the layout to use for the new directory "
- "(bushy or lawn). Default: %default")
- options, args = parser.parse_args()
-
- if not len(args) == 2:
- parser.error("source and destination must be given")
-
- logging.getLogger().addHandler(logging.StreamHandler())
- logging.getLogger().setLevel(0)
-
- source, dest = args
- migrate(source, dest, options.layout)
-
-
-if __name__ == '__main__':
- main()
Deleted: ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_layout.txt
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_layout.txt 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_layout.txt 2008-08-04 18:39:18 UTC (rev 89351)
@@ -1,283 +0,0 @@
-======================
-Blob directory layouts
-======================
-
-The internal structure of the blob directories is governed by so called
-`layouts`. The current default layout is called `bushy`.
-
-The original blob implementation used a layout that we now call `lawn` and
-which is still available for backwards compatibility.
-
-Layouts implement two methods: one for computing a relative path for an
-OID and one for turning a relative path back into an OID.
-
-Our terminology is roughly the same as used in `DirectoryStorage`.
-
-The `bushy` layout
-==================
-
-The bushy layout splits the OID into the 8 byte parts, reverses them and
-creates one directory level for each part, named by the hexlified
-representation of the byte value. This results in 8 levels of directories, the
-leaf directories being used for the revisions of the blobs and at most 256
-entries per directory level:
-
->>> from ZODB.blob import BushyLayout
->>> bushy = BushyLayout()
->>> bushy.oid_to_path('\x00\x00\x00\x00\x00\x00\x00\x00')
-'0x00/0x00/0x00/0x00/0x00/0x00/0x00/0x00'
->>> bushy.oid_to_path('\x00\x00\x00\x00\x00\x00\x00\x01')
-'0x01/0x00/0x00/0x00/0x00/0x00/0x00/0x00'
-
->>> bushy.path_to_oid('0x01/0x00/0x00/0x00/0x00/0x00/0x00/0x00')
-'\x00\x00\x00\x00\x00\x00\x00\x01'
->>> bushy.path_to_oid('0xff/0x00/0x00/0x00/0x00/0x00/0x00/0x00')
-'\x00\x00\x00\x00\x00\x00\x00\xff'
-
-Paths that do not represent an OID will cause a ValueError:
-
->>> bushy.path_to_oid('tmp')
-Traceback (most recent call last):
-ValueError: Not a valid OID path: `tmp`
-
-
-The `lawn` layout
-=================
-
-The lawn layout creates on directory for each blob named by the blob's hex
-representation of its OID. This has some limitations on various file systems
-like performance penalties or the inability to store more than a given number
-of blobs at the same time (e.g. 32k on ext3).
-
->>> from ZODB.blob import LawnLayout
->>> lawn = LawnLayout()
->>> lawn.oid_to_path('\x00\x00\x00\x00\x00\x00\x00\x00')
-'0x00'
->>> lawn.oid_to_path('\x00\x00\x00\x00\x00\x00\x00\x01')
-'0x01'
-
->>> lawn.path_to_oid('0x01')
-'\x00\x00\x00\x00\x00\x00\x00\x01'
-
-Paths that do not represent an OID will cause a ValueError:
-
->>> lawn.path_to_oid('tmp')
-Traceback (most recent call last):
-ValueError: Not a valid OID path: `tmp`
->>> lawn.path_to_oid('')
-Traceback (most recent call last):
-ValueError: Not a valid OID path: ``
-
-
-Auto-detecting the layout of a directory
-========================================
-
-To allow easier migration, we provide an auto-detection feature that analyses a
-blob directory and decides for a strategy to use. In general it prefers to
-choose the `bushy` layout, except if it determines that the directory has
-already been used to create a lawn structure.
-
->>> from ZODB.blob import auto_layout_select
-
-1. Non-existing directories will trigger a bushy layout:
-
->>> import tempfile
->>> import shutil
->>> d = tempfile.mkdtemp()
->>> shutil.rmtree(d)
->>> auto_layout_select(d)
-'bushy'
-
-2. Empty directories will trigger a bushy layout too:
-
->>> d = tempfile.mkdtemp()
->>> auto_layout_select(d)
-'bushy'
-
-3. If the directory contains a marker for the strategy it will be used:
-
->>> from ZODB.blob import LAYOUT_MARKER
->>> import os.path
->>> open(os.path.join(d, LAYOUT_MARKER), 'wb').write('bushy')
->>> auto_layout_select(d)
-'bushy'
->>> open(os.path.join(d, LAYOUT_MARKER), 'wb').write('lawn')
->>> auto_layout_select(d)
-'lawn'
->>> shutil.rmtree(d)
-
-4. If the directory does not contain a marker but other files, we assume that
-it was created with an earlier version of the blob implementation and uses our
-`lawn` layout:
-
->>> d = tempfile.mkdtemp()
->>> open(os.path.join(d, '0x0101'), 'wb').write('foo')
->>> auto_layout_select(d)
-'lawn'
->>> shutil.rmtree(d)
-
-
-Directory layout markers
-========================
-
-When the file system helper (FSH) is asked to create the directory structure,
-it will leave a marker with the choosen layout if no marker exists yet:
-
->>> from ZODB.blob import FilesystemHelper
->>> d = tempfile.mkdtemp()
->>> blobs = os.path.join(d, 'blobs')
->>> fsh = FilesystemHelper(blobs)
->>> fsh.layout_name
-'bushy'
->>> fsh.create()
->>> open(os.path.join(blobs, LAYOUT_MARKER), 'rb').read()
-'bushy'
-
-If the FSH finds a marker, then it verifies whether its content matches the
-strategy that was chosen. It will raise an exception if we try to work with a
-directory that has a different marker than the chosen strategy:
-
->>> fsh = FilesystemHelper(blobs, 'lawn')
->>> fsh.layout_name
-'lawn'
->>> fsh.create() # doctest: +ELLIPSIS
-Traceback (most recent call last):
-ValueError: Directory layout `lawn` selected for blob directory /.../blobs/, but marker found for layout `bushy`
->>> shutil.rmtree(blobs)
-
-This function interacts with the automatic detection in the way, that an
-unmarked directory will be marked the first time when it is auto-guessed and
-the marker will be used in the future:
-
->>> import ZODB.FileStorage
->>> from ZODB.blob import BlobStorage
->>> datafs = os.path.join(d, 'data.fs')
->>> base_storage = ZODB.FileStorage.FileStorage(datafs)
-
->>> os.mkdir(blobs)
->>> open(os.path.join(blobs, 'foo'), 'wb').write('foo')
->>> blob_storage = BlobStorage(blobs, base_storage)
->>> blob_storage.fshelper.layout_name
-'lawn'
->>> open(os.path.join(blobs, LAYOUT_MARKER), 'rb').read()
-'lawn'
->>> blob_storage = BlobStorage(blobs, base_storage, layout='bushy') # doctest: +ELLIPSIS
-Traceback (most recent call last):
-ValueError: Directory layout `bushy` selected for blob directory /.../blobs/, but marker found for layout `lawn`
-
-
->>> shutil.rmtree(d)
-
-
-Migrating between directory layouts
-===================================
-
-A script called `migrateblobs.py` is distributed with the ZODB for offline
-migration capabilities between different directory layouts. It can migrate any
-blob directory layout to any other layout. It leaves the original blob
-directory untouched (except from eventually creating a temporary directory and
-the storage layout marker).
-
-The migration is accessible as a library function:
-
->>> from ZODB.scripts.migrateblobs import migrate
-
-Create a `lawn` directory structure and migrate it to the new `bushy` one:
-
->>> from ZODB.blob import FilesystemHelper
->>> d = tempfile.mkdtemp()
->>> old = os.path.join(d, 'old')
->>> old_fsh = FilesystemHelper(old, 'lawn')
->>> old_fsh.create()
->>> blob1 = old_fsh.getPathForOID(7039, create=True)
->>> blob2 = old_fsh.getPathForOID(10, create=True)
->>> blob3 = old_fsh.getPathForOID(7034, create=True)
->>> open(os.path.join(blob1, 'foo'), 'wb').write('foo')
->>> open(os.path.join(blob1, 'foo2'), 'wb').write('bar')
->>> open(os.path.join(blob2, 'foo3'), 'wb').write('baz')
->>> open(os.path.join(blob2, 'foo4'), 'wb').write('qux')
->>> open(os.path.join(blob3, 'foo5'), 'wb').write('quux')
->>> open(os.path.join(blob3, 'foo6'), 'wb').write('corge')
-
-Committed blobs have their permissions set to 000
-
-The migration function is called with the old and the new path and the layout
-that shall be used for the new directory:
-
->>> bushy = os.path.join(d, 'bushy')
->>> migrate(old, bushy, 'bushy') # doctest: +ELLIPSIS +NORMALIZE_WHITESPACE
-Migrating blob data from `/.../old` (lawn) to `/.../bushy` (bushy)
- OID: 0x1b7f - 2 files
- OID: 0x0a - 2 files
- OID: 0x1b7a - 2 files
-
-The new directory now contains the same files in different directories, but
-with the same sizes and permissions:
-
->>> import string
->>> def stat(path):
-... s = os.stat(path)
-... print "%s\t%s\t%s" % (string.rjust(oct(s.st_mode), 10), s.st_size, path)
->>> def ls(path):
-... for p, dirs, files in os.walk(path):
-... stat(p)
-... for file in files:
-... stat(os.path.join(p, file))
->>> ls(bushy)
- 040700 4096 /.../bushy
- 0100644 5 /.../bushy/.layout
- 040700 4096 /.../bushy/0x7a
- 040700 4096 /.../bushy/0x7a/0x1b
- 040700 4096 /.../bushy/0x7a/0x1b/0x00
- 040700 4096 /.../bushy/0x7a/0x1b/0x00/0x00
- 040700 4096 /.../bushy/0x7a/0x1b/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x7a/0x1b/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x7a/0x1b/0x00/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x7a/0x1b/0x00/0x00/0x00/0x00/0x00/0x00
- 0100644 5 /.../bushy/0x7a/0x1b/0x00/0x00/0x00/0x00/0x00/0x00/foo6
- 0100644 4 /.../bushy/0x7a/0x1b/0x00/0x00/0x00/0x00/0x00/0x00/foo5
- 040700 4096 /.../bushy/tmp
- 040700 4096 /.../bushy/0x0a
- 040700 4096 /.../bushy/0x0a/0x00
- 040700 4096 /.../bushy/0x0a/0x00/0x00
- 040700 4096 /.../bushy/0x0a/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x0a/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x0a/0x00/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x0a/0x00/0x00/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x0a/0x00/0x00/0x00/0x00/0x00/0x00/0x00
- 0100644 3 /.../bushy/0x0a/0x00/0x00/0x00/0x00/0x00/0x00/0x00/foo4
- 0100644 3 /.../bushy/0x0a/0x00/0x00/0x00/0x00/0x00/0x00/0x00/foo3
- 040700 4096 /.../bushy/0x7f
- 040700 4096 /.../bushy/0x7f/0x1b
- 040700 4096 /.../bushy/0x7f/0x1b/0x00
- 040700 4096 /.../bushy/0x7f/0x1b/0x00/0x00
- 040700 4096 /.../bushy/0x7f/0x1b/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x7f/0x1b/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x7f/0x1b/0x00/0x00/0x00/0x00/0x00
- 040700 4096 /.../bushy/0x7f/0x1b/0x00/0x00/0x00/0x00/0x00/0x00
- 0100644 3 /.../bushy/0x7f/0x1b/0x00/0x00/0x00/0x00/0x00/0x00/foo
- 0100644 3 /.../bushy/0x7f/0x1b/0x00/0x00/0x00/0x00/0x00/0x00/foo2
-
-We can also migrate the bushy layout back to the lawn layout:
-
->>> lawn = os.path.join(d, 'lawn')
->>> migrate(bushy, lawn, 'lawn')
-Migrating blob data from `/.../bushy` (bushy) to `/.../lawn` (lawn)
- OID: 0x1b7a - 2 files
- OID: 0x0a - 2 files
- OID: 0x1b7f - 2 files
->>> ls(lawn)
- 040700 4096 /.../lawn
- 0100644 4 /.../lawn/.layout
- 040700 4096 /.../lawn/0x1b7f
- 0100644 3 /.../lawn/0x1b7f/foo
- 0100644 3 /.../lawn/0x1b7f/foo2
- 040700 4096 /.../lawn/tmp
- 040700 4096 /.../lawn/0x0a
- 0100644 3 /.../lawn/0x0a/foo4
- 0100644 3 /.../lawn/0x0a/foo3
- 040700 4096 /.../lawn/0x1b7a
- 0100644 5 /.../lawn/0x1b7a/foo6
- 0100644 4 /.../lawn/0x1b7a/foo5
-
->>> shutil.rmtree(d)
Modified: ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_packing.txt
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_packing.txt 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_packing.txt 2008-08-04 18:39:18 UTC (rev 89351)
@@ -240,6 +240,37 @@
>>> os.path.exists(os.path.split(fns[0])[0])
False
+Avoiding parallel packs
+=======================
+
+Blob packing (similar to FileStorage) can only be run once at a time. For
+this, a flag (_blobs_pack_is_in_progress) is set. If the pack method is called
+while this flag is set, it will refuse to perform another pack, until the flag
+is reset:
+
+ >>> blob_storage._blobs_pack_is_in_progress
+ False
+ >>> blob_storage._blobs_pack_is_in_progress = True
+ >>> blob_storage.pack(packtime, referencesf)
+ Traceback (most recent call last):
+ BlobStorageError: Already packing
+ >>> blob_storage._blobs_pack_is_in_progress = False
+ >>> blob_storage.pack(packtime, referencesf)
+
+We can also see, that the flag is set during the pack, by leveraging the
+knowledge that the underlying storage's pack method is also called:
+
+ >>> def dummy_pack(time, ref):
+ ... print "_blobs_pack_is_in_progress =", blob_storage._blobs_pack_is_in_progress
+ ... return base_pack(time, ref)
+ >>> base_pack = base_storage.pack
+ >>> base_storage.pack = dummy_pack
+ >>> blob_storage.pack(packtime, referencesf)
+ _blobs_pack_is_in_progress = True
+ >>> blob_storage._blobs_pack_is_in_progress
+ False
+ >>> base_storage.pack = base_pack
+
Clean up our blob directory:
>>> shutil.rmtree(blob_dir)
Modified: ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_tempdir.txt
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_tempdir.txt 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_tempdir.txt 2008-08-04 18:39:18 UTC (rev 89351)
@@ -32,7 +32,7 @@
>>> from ZODB.DB import DB
>>> from tempfile import mkdtemp
>>> import os.path
- >>> base_storage = MappingStorage('test')
+ >>> base_storage = MappingStorage("test")
>>> blob_dir = mkdtemp()
>>> blob_storage = BlobStorage(blob_dir, base_storage)
>>> database = DB(blob_storage)
Modified: ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_transaction.txt
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_transaction.txt 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/blob_transaction.txt 2008-08-04 18:39:18 UTC (rev 89351)
@@ -353,9 +353,9 @@
>>> base_storage = DummyBaseStorage()
>>> blob_dir2 = mkdtemp()
>>> blob_storage2 = BlobStorage(blob_dir2, base_storage)
- >>> committed_blob_dir = blob_storage2.fshelper.getPathForOID(0)
- >>> os.makedirs(committed_blob_dir)
- >>> committed_blob_file = blob_storage2.fshelper.getBlobFilename(0, 0)
+ >>> committed_blob_dir = os.path.join(blob_dir2, '0')
+ >>> committed_blob_file = os.path.join(committed_blob_dir, '0.blob')
+ >>> os.mkdir(committed_blob_dir)
>>> open(os.path.join(committed_blob_file), 'w').write('foo')
>>> os.path.exists(committed_blob_file)
True
Modified: ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/testblob.py
===================================================================
--- ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/testblob.py 2008-08-04 17:47:44 UTC (rev 89350)
+++ ZODB/branches/ctheune-bushy-directory/src/ZODB/tests/testblob.py 2008-08-04 18:39:18 UTC (rev 89351)
@@ -105,6 +105,7 @@
self.here = os.getcwd()
os.chdir(self.test_dir)
self.storagefile = 'Data.fs'
+ os.mkdir('blobs')
self.blob_dir = 'blobs'
def tearDown(self):
@@ -482,7 +483,7 @@
We can access the blob correctly:
>>> tmpstore.loadBlob(blob_oid, tid) # doctest: +ELLIPSIS
- '.../0x01/0x00/0x00/0x00/0x00/0x00/0x00/0x00/0x...blob'
+ '.../0x01/0x...blob'
Clean up:
@@ -507,12 +508,6 @@
setUp=ZODB.tests.util.setUp,
tearDown=ZODB.tests.util.tearDown,
))
- suite.addTest(doctest.DocFileSuite(
- "blob_layout.txt",
- optionflags=doctest.ELLIPSIS|doctest.NORMALIZE_WHITESPACE|doctest.REPORT_NDIFF,
- setUp=ZODB.tests.util.setUp,
- tearDown=ZODB.tests.util.tearDown,
- ))
suite.addTest(doctest.DocTestSuite(
setUp=ZODB.tests.util.setUp,
tearDown=ZODB.tests.util.tearDown,
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