14
15
# along with this program; if not, write to the Free Software
15
16
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18
Stores are the main data-storage mechanism for Bazaar-NG.
18
"""Stores are the main data-storage mechanism for Bazaar-NG.
20
20
A store is a simple write-once container indexed by a universally
24
import os, tempfile, types, osutils, gzip, errno
25
from stat import ST_SIZE
21
unique ID, which is typically the SHA-1 of the content."""
23
__copyright__ = "Copyright (C) 2005 Canonical Ltd."
24
__author__ = "Martin Pool <mbp@canonical.com>"
26
import os, tempfile, types, osutils
26
27
from StringIO import StringIO
27
from bzrlib.errors import BzrError
28
from bzrlib.trace import mutter
28
from trace import mutter
31
31
######################################################################
58
58
>>> st['123123'].read()
61
TODO: Atomic add by writing to a temporary file and renaming.
63
In bzr 0.0.5 and earlier, files within the store were marked
64
readonly on disk. This is no longer done but existing stores need
61
:todo: Atomic add by writing to a temporary file and renaming.
63
:todo: Perhaps automatically transform to/from XML in a method?
64
Would just need to tell the constructor what class to
67
:todo: Even within a simple disk store like this, we could
68
gzip the files. But since many are less than one disk
69
block, that might not help a lot.
68
73
def __init__(self, basedir):
74
"""ImmutableStore constructor."""
69
75
self._basedir = basedir
71
77
def _path(self, id):
72
if '\\' in id or '/' in id:
73
raise ValueError("invalid store id %r" % id)
74
78
return os.path.join(self._basedir, id)
76
80
def __repr__(self):
77
81
return "%s(%r)" % (self.__class__.__name__, self._basedir)
79
def add(self, f, fileid, compressed=True):
83
def add(self, f, fileid):
80
84
"""Add contents of a file into the store.
82
f -- An open file, or file-like object."""
83
# FIXME: Only works on files that will fit in memory
85
from bzrlib.atomicfile import AtomicFile
86
:param f: An open file, or file-like object."""
87
# FIXME: Only works on smallish files
88
# TODO: Can be optimized by copying at the same time as
87
90
mutter("add store entry %r" % (fileid))
88
91
if isinstance(f, types.StringTypes):
93
p = self._path(fileid)
94
if os.access(p, os.F_OK) or os.access(p + '.gz', os.F_OK):
95
raise BzrError("store %r already contains id %r" % (self._basedir, fileid))
101
af = AtomicFile(fn, 'wb')
104
gf = gzip.GzipFile(mode='wb', fileobj=af)
114
def copy_multi(self, other, ids, permit_failure=False):
115
"""Copy texts for ids from other into self.
117
If an id is present in self, it is skipped.
119
Returns (count_copied, failed), where failed is a collection of ids
120
that could not be copied.
122
pb = bzrlib.ui.ui_factory.progress_bar()
124
pb.update('preparing to copy')
125
to_copy = [id for id in ids if id not in self]
126
if isinstance(other, ImmutableStore):
127
return self.copy_multi_immutable(other, to_copy, pb)
132
pb.update('copy', count, len(to_copy))
133
if not permit_failure:
134
self.add(other[id], id)
143
if not permit_failure:
144
assert count == len(to_copy)
148
def copy_multi_immutable(self, other, to_copy, pb, permit_failure=False):
149
from shutil import copyfile
154
other_p = other._path(id)
158
if e.errno == errno.ENOENT:
159
if not permit_failure:
160
copyfile(other_p+".gz", p+".gz")
163
copyfile(other_p+".gz", p+".gz")
165
if e.errno == errno.ENOENT:
173
pb.update('copy', count, len(to_copy))
174
assert count == len(to_copy)
95
if fileid not in self:
96
filename = self._path(fileid)
97
f = file(filename, 'wb')
102
osutils.make_readonly(filename)
179
105
def __contains__(self, fileid):
181
p = self._path(fileid)
182
return (os.access(p, os.R_OK)
183
or os.access(p + '.gz', os.R_OK))
107
return os.access(self._path(fileid), os.R_OK)
185
# TODO: Guard against the same thing being stored twice, compressed and uncompresse
187
110
def __iter__(self):
188
for f in os.listdir(self._basedir):
190
# TODO: case-insensitive?
196
return len(os.listdir(self._basedir))
111
return iter(os.listdir(self._basedir))
199
113
def __getitem__(self, fileid):
200
114
"""Returns a file reading from a particular entry."""
201
p = self._path(fileid)
203
return gzip.GzipFile(p + '.gz', 'rb')
205
if e.errno != errno.ENOENT:
211
if e.errno != errno.ENOENT:
214
raise IndexError(fileid)
217
def total_size(self):
218
"""Return (count, bytes)
220
This is the (compressed) size stored on disk, not the size of
228
total += os.stat(p)[ST_SIZE]
230
total += os.stat(p + '.gz')[ST_SIZE]
115
return file(self._path(fileid), 'rb')
117
def delete_all(self):
121
def delete(self, fileid):
122
"""Remove nominated store entry.
124
Most stores will be add-only."""
125
filename = self._path(fileid)
126
## osutils.make_writable(filename)
130
"""Remove store; only allowed if it is empty."""
131
os.rmdir(self._basedir)
132
mutter("%r destroyed" % self)
added
removed
bzrlib/store.py
