def save_and_backup(self):
"""
Save file but keep backup first.
The last step would shift a list of files below:
weblib.dat.tmp (newly saved)
weblib.dat (current weblib)
weblib.dat.1
weblib.dat.2
weblib.dat.3
weblib.dat.4
weblib.dat.5
Note only weblib.dat.tmp is guarantine to exist before shift.
"""
self.lock.acquire()
try:
# first save to tmp filename
tmp_pathname = self.pathname + '.tmp'
self.save(tmp_pathname)
# shift backup files
files = [tmp_pathname, self.pathname]
for i in range(self.BACKUP_COUNT):
files.append('%s.%s' % (self.pathname, i+1))
fileutil.shift_files(files)
finally:
self.lock.release()
def save(self):
today = str(datetime.date.today())
log.info('Saving config file: %s %s' % (self.config_path, today))
self.set('_system.updated', today)
wpath = self.config_path + '.tmp'
bpath = self.config_path + '.~'
fp = file(wpath,'wb')
try:
self._serialize(fp)
finally:
fp.close()
from minds.util import fileutil
fileutil.shift_files([wpath, self.config_path, bpath])
def test_shift_files(self):
A = testpath / 'a'
B = testpath / 'b'
C = testpath / 'c'
if A.exists(): A.remove()
if B.exists(): B.remove()
if C.exists(): C.remove()
# -- test 0 ------------------------------------------------------------------------
# ok if non of them exist
fileutil.shift_files([A,B,C])
self.assert_(not A.exists())
self.assert_(not B.exists())
self.assert_(not C.exists())
# -- test 1 ------------------------------------------------------------------------
file(A,'w').write('1')
# A->B (new file)
fileutil.shift_files([A,B])
self.assert_(not A.exists())
self.assertEqual(file(B).read(), '1')
# -- test 2 ------------------------------------------------------------------------
file(A,'w').write('2')
# A->B (existing file)
fileutil.shift_files([A,B])
self.assert_(not A.exists())
self.assertEqual(file(B).read(), '2')
# -- test 3 ------------------------------------------------------------------------
file(A,'w').write('3')
# A->B->C (new file)
fileutil.shift_files([A,B,C])
self.assert_(not A.exists())
self.assertEqual(file(B).read(), '3')
self.assertEqual(file(C).read(), '2')
# -- test 4 ------------------------------------------------------------------------
file(A,'w').write('4')
# A->B->C (existing file)
fileutil.shift_files([A,B,C])
self.assert_(not A.exists())
self.assertEqual(file(B).read(), '4')
self.assertEqual(file(C).read(), '3')
# -- test 5 ------------------------------------------------------------------------
file(A,'w').write('5')
# A->xBx->C (existing file)
B.remove()
fileutil.shift_files([A,B,C])
self.assert_(not A.exists())
self.assertEqual(file(B).read(), '5')
self.assert_(not C.exists())