1
# Copyright (C) 2005 by Canonical Development Ltd
3
# This program is free software; you can redistribute it and/or modify
4
# it under the terms of the GNU General Public License as published by
5
# the Free Software Foundation; either version 2 of the License, or
6
# (at your option) any later version.
8
# This program is distributed in the hope that it will be useful,
9
# but WITHOUT ANY WARRANTY; without even the implied warranty of
10
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
# GNU General Public License for more details.
13
# You should have received a copy of the GNU General Public License
14
# along with this program; if not, write to the Free Software
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
Stores are the main data-storage mechanism for Bazaar-NG.
20
A store is a simple write-once container indexed by a universally
29
from stat import ST_SIZE
30
from StringIO import StringIO
32
from bzrlib.errors import BzrError
33
from bzrlib.trace import mutter
35
import bzrlib.osutils as osutils
38
######################################################################
41
class StoreError(Exception):
45
class ImmutableStore(object):
46
"""Store that holds files indexed by unique names.
48
Files can be added, but not modified once they are in. Typically
49
the hash is used as the name, or something else known to be unique,
52
>>> st = ImmutableScratchStore()
54
>>> st.add(StringIO('hello'), 'aa')
60
You are not allowed to add an id that is already present.
62
Entries can be retrieved as files, which may then be read.
64
>>> st.add(StringIO('goodbye'), '123123')
65
>>> st['123123'].read()
68
TODO: Atomic add by writing to a temporary file and renaming.
70
In bzr 0.0.5 and earlier, files within the store were marked
71
readonly on disk. This is no longer done but existing stores need
75
def __init__(self, basedir):
76
self._basedir = basedir
78
def _path(self, entry_id):
79
if not isinstance(entry_id, basestring):
80
raise TypeError(type(entry_id))
81
if '\\' in entry_id or '/' in entry_id:
82
raise ValueError("invalid store id %r" % entry_id)
83
return os.path.join(self._basedir, entry_id)
86
return "%s(%r)" % (self.__class__.__name__, self._basedir)
88
def add(self, f, fileid, compressed=True):
89
"""Add contents of a file into the store.
91
f -- An open file, or file-like object."""
92
# FIXME: Only works on files that will fit in memory
94
from bzrlib.atomicfile import AtomicFile
96
mutter("add store entry %r" % (fileid))
97
if isinstance(f, types.StringTypes):
102
p = self._path(fileid)
103
if os.access(p, os.F_OK) or os.access(p + '.gz', os.F_OK):
104
raise BzrError("store %r already contains id %r" % (self._basedir, fileid))
110
af = AtomicFile(fn, 'wb')
113
gf = gzip.GzipFile(mode='wb', fileobj=af)
123
def copy_multi(self, other, ids, permit_failure=False):
124
"""Copy texts for ids from other into self.
126
If an id is present in self, it is skipped.
128
Returns (count_copied, failed), where failed is a collection of ids
129
that could not be copied.
131
pb = bzrlib.ui.ui_factory.progress_bar()
133
pb.update('preparing to copy')
134
to_copy = [id for id in ids if id not in self]
135
if isinstance(other, ImmutableStore):
136
return self.copy_multi_immutable(other, to_copy, pb,
137
permit_failure=permit_failure)
142
pb.update('copy', count, len(to_copy))
143
if not permit_failure:
144
self.add(other[id], id)
153
if not permit_failure:
154
assert count == len(to_copy)
158
def copy_multi_immutable(self, other, to_copy, pb, permit_failure=False):
159
from shutil import copyfile
164
other_p = other._path(id)
168
if e.errno == errno.ENOENT:
169
if not permit_failure:
170
copyfile(other_p+".gz", p+".gz")
173
copyfile(other_p+".gz", p+".gz")
175
if e.errno == errno.ENOENT:
183
pb.update('copy', count, len(to_copy))
184
assert count == len(to_copy)
189
def __contains__(self, fileid):
191
p = self._path(fileid)
192
return (os.access(p, os.R_OK)
193
or os.access(p + '.gz', os.R_OK))
195
# TODO: Guard against the same thing being stored twice, compressed and uncompresse
198
for f in os.listdir(self._basedir):
200
# TODO: case-insensitive?
206
return len(os.listdir(self._basedir))
209
def __getitem__(self, fileid):
210
"""Returns a file reading from a particular entry."""
211
p = self._path(fileid)
213
return gzip.GzipFile(p + '.gz', 'rb')
215
if e.errno != errno.ENOENT:
221
if e.errno != errno.ENOENT:
224
raise KeyError(fileid)
227
def total_size(self):
228
"""Return (count, bytes)
230
This is the (compressed) size stored on disk, not the size of
238
total += os.stat(p)[ST_SIZE]
240
total += os.stat(p + '.gz')[ST_SIZE]
247
class ImmutableScratchStore(ImmutableStore):
248
"""Self-destructing test subclass of ImmutableStore.
250
The Store only exists for the lifetime of the Python object.
251
Obviously you should not put anything precious in it.
254
ImmutableStore.__init__(self, tempfile.mkdtemp())
257
for f in os.listdir(self._basedir):
258
fpath = os.path.join(self._basedir, f)
259
# needed on windows, and maybe some other filesystems
260
os.chmod(fpath, 0600)
262
os.rmdir(self._basedir)
263
mutter("%r destroyed" % self)
added
removed
bzrlib/store.py
