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
17
# TODO: Could remember a bias towards whether a particular store is typically
21
Stores are the main data-storage mechanism for Bazaar-NG.
23
A store is a simple write-once container indexed by a universally
32
from stat import ST_SIZE
33
from StringIO import StringIO
35
from bzrlib.errors import BzrError
36
from bzrlib.trace import mutter
38
import bzrlib.osutils as osutils
41
######################################################################
44
class StoreError(Exception):
48
class ImmutableStore(object):
49
"""Store that holds files indexed by unique names.
51
Files can be added, but not modified once they are in. Typically
52
the hash is used as the name, or something else known to be unique,
55
>>> st = ImmutableScratchStore()
57
>>> st.add(StringIO('hello'), 'aa')
63
You are not allowed to add an id that is already present.
65
Entries can be retrieved as files, which may then be read.
67
>>> st.add(StringIO('goodbye'), '123123')
68
>>> st['123123'].read()
71
TODO: Atomic add by writing to a temporary file and renaming.
73
In bzr 0.0.5 and earlier, files within the store were marked
74
readonly on disk. This is no longer done but existing stores need
78
def __init__(self, basedir):
79
self._basedir = basedir
81
def _path(self, entry_id):
82
if not isinstance(entry_id, basestring):
83
raise TypeError(type(entry_id))
84
if '\\' in entry_id or '/' in entry_id:
85
raise ValueError("invalid store id %r" % entry_id)
86
return os.path.join(self._basedir, entry_id)
89
return "%s(%r)" % (self.__class__.__name__, self._basedir)
91
def add(self, f, fileid, compressed=True):
92
"""Add contents of a file into the store.
94
f -- An open file, or file-like object."""
95
# FIXME: Only works on files that will fit in memory
97
from bzrlib.atomicfile import AtomicFile
99
mutter("add store entry %r" % (fileid))
100
if isinstance(f, types.StringTypes):
105
p = self._path(fileid)
106
if os.access(p, os.F_OK) or os.access(p + '.gz', os.F_OK):
107
raise BzrError("store %r already contains id %r" % (self._basedir, fileid))
113
af = AtomicFile(fn, 'wb')
116
gf = gzip.GzipFile(mode='wb', fileobj=af)
126
def copy_multi(self, other, ids, permit_failure=False):
127
"""Copy texts for ids from other into self.
129
If an id is present in self, it is skipped.
131
Returns (count_copied, failed), where failed is a collection of ids
132
that could not be copied.
134
pb = bzrlib.ui.ui_factory.progress_bar()
136
pb.update('preparing to copy')
137
to_copy = [id for id in ids if id not in self]
138
if isinstance(other, ImmutableStore):
139
return self.copy_multi_immutable(other, to_copy, pb,
140
permit_failure=permit_failure)
145
pb.update('copy', count, len(to_copy))
146
if not permit_failure:
147
self.add(other[id], id)
156
if not permit_failure:
157
assert count == len(to_copy)
161
def copy_multi_immutable(self, other, to_copy, pb, permit_failure=False):
162
from shutil import copyfile
167
other_p = other._path(id)
171
if e.errno == errno.ENOENT:
172
if not permit_failure:
173
copyfile(other_p+".gz", p+".gz")
176
copyfile(other_p+".gz", p+".gz")
178
if e.errno == errno.ENOENT:
186
pb.update('copy', count, len(to_copy))
187
assert count == len(to_copy)
192
def __contains__(self, fileid):
194
p = self._path(fileid)
195
return (os.access(p, os.R_OK)
196
or os.access(p + '.gz', os.R_OK))
198
# TODO: Guard against the same thing being stored twice,
199
# compressed and uncompressed
202
for f in os.listdir(self._basedir):
204
# TODO: case-insensitive?
210
return len(os.listdir(self._basedir))
213
def __getitem__(self, fileid):
214
"""Returns a file reading from a particular entry."""
215
p = self._path(fileid)
217
return gzip.GzipFile(p + '.gz', 'rb')
219
if e.errno != errno.ENOENT:
225
if e.errno != errno.ENOENT:
228
raise KeyError(fileid)
231
def total_size(self):
232
"""Return (count, bytes)
234
This is the (compressed) size stored on disk, not the size of
242
total += os.stat(p)[ST_SIZE]
244
total += os.stat(p + '.gz')[ST_SIZE]
251
class ImmutableScratchStore(ImmutableStore):
252
"""Self-destructing test subclass of ImmutableStore.
254
The Store only exists for the lifetime of the Python object.
255
Obviously you should not put anything precious in it.
258
ImmutableStore.__init__(self, tempfile.mkdtemp())
261
for f in os.listdir(self._basedir):
262
fpath = os.path.join(self._basedir, f)
263
# needed on windows, and maybe some other filesystems
264
os.chmod(fpath, 0600)
266
os.rmdir(self._basedir)
267
mutter("%r destroyed" % self)
added
removed
bzrlib/store.py
