def remove_reference(self, name, expire=MARKER):
file_path = self.get_reference_path(name)
temporary_file_path = file_path + '.' + make_uuid_hash()
move_file(file_path, temporary_file_path, retries=self.retries, retry_errno=self.retry_errno)
references = self._get_references(temporary_file_path, name='')
if name in references:
references.remove(name)
# Validate if references still exists
if references:
if expire is MARKER:
# Dont use expire, we only need to know if file exists
expire = None
for name in references:
path = self.get_file_path(name)
if not self._contains(path, expire=expire):
references.remove(name)
if references:
references = maybe_list(references)
references.append(b_linesep)
put_binary_on_file(
file_path,
binary=bytes_join(b_linesep, references),
mode='ab',
retries=self.retries,
retry_errno=self.retry_errno)
self._delete_path(temporary_file_path)
def lock(self, name, timeout=MARKER, delete_lock_on_timeout=MARKER):
name_256 = self.format_name(name)
lock_code = make_uuid_hash()
lock_name = '%s %s %s' % (DOMAIN_NAME, PROCESS_ID, lock_code)
position = None
while position is None:
self.memcache.add(name_256, '0')
position = self.memcache.incr(name_256)
if position is 1:
# Me first! Thank you!
return None
# Define expire time
expire_time = None
if timeout is MARKER:
timeout = self.timeout
if timeout:
expire_time = NOW_TIME() + int(timeout)
# Lock my wait position
position_name_256 = self.format_position_name(name_256, position)
self.memcache.set(position_name_256, lock_name)
# Wait until my locked position is cleaned
while self._contains(position_name_256):
sleep(0.1)
if expire_time and NOW_TIME() > expire_time:
# Im done! No more wait for me!
if not self.memcache.delete(position_name_256):
# Wait.. after all.. its show time!
return None
if delete_lock_on_timeout is MARKER:
delete_lock_on_timeout = self.delete_lock_on_timeout
if delete_lock_on_timeout:
self.unlock(name)
# Sorry, you need to do everything again
return self.lock(name, timeout=timeout, delete_lock_on_timeout=delete_lock_on_timeout)
else:
# Clean invalid locks!
if self.clean_junk_locks(name_256):
# Go again
return self.lock(name, timeout=timeout, delete_lock_on_timeout=delete_lock_on_timeout)
message = 'Timeout (%ss) on lock "%s". Delete (%s*) to unlock' % (timeout, name, name_256)
raise LockTimeout(message, name_256)
self.memcache.delete(position_name_256)
def make_key(self):
return make_uuid_hash()
def lock(self, name, timeout=MARKER, delete_lock_on_timeout=MARKER):
path = self.get_file_path(name)
lock_code = make_uuid_hash()
lock_name = '%s %s %s' % (DOMAIN_NAME, PROCESS_ID, lock_code)
lock_name_to_file = lock_name + NEW_LINE
position = None
while position is None:
# Enter on wait list
put_binary_on_file(path, lock_name_to_file, mode='a', retries=self.retries, retry_errno=self.retry_errno)
# Find my wait position
binary = get_file_binary(path, mode='r', retries=self.retries, retry_errno=self.retry_errno)
if binary:
for i, code in enumerate(binary.splitlines()):
if code.split()[-1] == lock_code:
position = i
break
if position is 0:
# Me first! Thank you!
return
# Define expire time
expire_time = None
if timeout is MARKER:
timeout = self.timeout
if timeout:
expire_time = NOW_TIME() + int(timeout)
# Lock my wait position
position_path = '%s.%s' % (path, position)
put_binary_on_file(position_path, lock_name, retries=self.retries, retry_errno=self.retry_errno)
# Wait until my locked position is cleaned
while isfile(position_path):
sleep(0.1)
if expire_time and NOW_TIME() > expire_time:
# Im done! No more wait for me!
try:
remove_file(position_path)
except OSError as error:
if error.errno is errno.ENOENT:
# Wait.. after all.. its show time!
return None
else:
raise
if delete_lock_on_timeout is MARKER:
delete_lock_on_timeout = self.delete_lock_on_timeout
if delete_lock_on_timeout:
self.unlock(name)
# Sorry, you need to do everything again
return self.lock(name, timeout=timeout, delete_lock_on_timeout=delete_lock_on_timeout)
else:
# Clean locks!
self.clean_junk_locks_as_daemon()
message = 'Timeout (%ss) on lock "%s". Delete (%s*) to unlock' % (timeout, name, path)
raise LockTimeout(message, position_path)
remove_file_quietly(position_path, retries=self.retries, retry_errno=self.retry_errno)