def atomic_lock(lock_dir, lock_name, lifetime=60):
"""A atomic, NFS safe implementation of a file lock.
Uses `flufl.lock` under the hood. Can be used as a context manager::
with atomic_lock(settings.TMP_PATH, 'extraction-1234'):
extract_xpi(...)
:return: `True` if the lock was attained, we are owning the lock,
`False` if there is an already existing lock.
"""
lock_name = lock_name + '.lock'
count = _lock_count.get(lock_name, 0)
log.debug('Acquiring lock %s, count is %d.' % (lock_name, count))
lock_name = os.path.join(lock_dir, lock_name)
lock = flufl.lock.Lock(lock_name, lifetime=timedelta(seconds=lifetime))
try:
# set `timeout=0` to avoid any process blocking but catch the
# TimeOutError raised instead.
lock.lock(timeout=timedelta(seconds=0))
except flufl.lock.AlreadyLockedError:
# This process already holds the lock
yield False
except flufl.lock.TimeOutError:
# Some other process holds the lock.
# Let's break the lock if it has expired. Unfortunately
# there's a bug in flufl.lock so let's do this manually.
# Bug: https://gitlab.com/warsaw/flufl.lock/merge_requests/1
release_time = lock._releasetime
max_release_time = release_time + flufl.lock._lockfile.CLOCK_SLOP
if (release_time != -1 and datetime.now() > max_release_time):
# Break the lock and try to aquire again
lock._break()
lock.lock(timeout=timedelta(seconds=0))
yield lock.is_locked
else:
# Already locked
yield False
else:
# Is usually `True` but just in case there were some weird `lifetime`
# values set we return the check if we really attained the lock.
yield lock.is_locked
if lock.is_locked:
log.debug('Releasing lock %s.' % lock.details[2])
lock.unlock()
def atomic_lock(lock_dir, lock_name, lifetime=60):
"""A atomic, NFS safe implementation of a file lock.
Uses `flufl.lock` under the hood. Can be used as a context manager::
with atomic_lock(settings.TMP_PATH, 'extraction-1234'):
extract_xpi(...)
:return: `True` if the lock was attained, we are owning the lock,
`False` if there is an already existing lock.
"""
lock_name = lock_name + '.lock'
count = _lock_count.get(lock_name, 0)
log.debug('Acquiring lock %s, count is %d.' % (lock_name, count))
lock_name = os.path.join(lock_dir, lock_name)
lock = flufl.lock.Lock(lock_name, lifetime=timedelta(seconds=lifetime))
try:
# set `timeout=0` to avoid any process blocking but catch the
# TimeOutError raised instead.
lock.lock(timeout=timedelta(seconds=0))
except flufl.lock.AlreadyLockedError:
# This process already holds the lock
yield False
except flufl.lock.TimeOutError:
# Some other process holds the lock.
# Let's break the lock if it has expired. Unfortunately
# there's a bug in flufl.lock so let's do this manually.
# Bug: https://gitlab.com/warsaw/flufl.lock/merge_requests/1
release_time = lock._releasetime
max_release_time = release_time + flufl.lock._lockfile.CLOCK_SLOP
if (release_time != -1 and datetime.now() > max_release_time):
# Break the lock and try to aquire again
lock._break()
lock.lock(timeout=timedelta(seconds=0))
yield lock.is_locked
else:
# Already locked
yield False
else:
# Is usually `True` but just in case there were some weird `lifetime`
# values set we return the check if we really attained the lock.
yield lock.is_locked
if lock.is_locked:
log.debug('Releasing lock %s.' % lock.details[2])
lock.unlock()
def test_atomic_lock_with():
lock = flufl.lock.Lock('/tmp/test-atomic-lock1.lock')
assert not lock.is_locked
lock.lock()
assert lock.is_locked
with utils.atomic_lock('/tmp/', 'test-atomic-lock1') as lock_attained:
assert not lock_attained
lock.unlock()
with utils.atomic_lock('/tmp/', 'test-atomic-lock1') as lock_attained:
assert lock_attained
def test_atomic_lock_with():
lock = flufl.lock.Lock('/tmp/test-atomic-lock1.lock')
assert not lock.is_locked
lock.lock()
assert lock.is_locked
with utils.atomic_lock('/tmp/', 'test-atomic-lock1') as lock_attained:
assert not lock_attained
lock.unlock()
with utils.atomic_lock('/tmp/', 'test-atomic-lock1') as lock_attained:
assert lock_attained
def _get_request_content(self, path):
"""
Return a dictionary with the content of the given YAML file path.
Locks the request directory while loading.
Raise an exception on failure.
"""
lock_path = os.path.join(self.dir, ".lock")
lock = flufl.lock.Lock(lock_path, lifetime=_requests_lock_lifetime)
# This may raise a TimeoutError, which the caller will handle.
lock.lock(timeout=_requests_lock_timeout)
# Try returning the file content. Unlock in any case.
try:
with open(path) as stream:
return yaml.safe_load(stream)
finally:
lock.unlock()
def main():
"""
Put a request file according to the push that invoked this script.
"""
env = os.environ
if ("GL_REPO" not in env) or ("GL_USER" not in env):
return 1
repo = env["GL_REPO"]
user = env["GL_USER"]
if not repo or not user:
return 2
# Admin repository doesn't trigger requests.
if repo == "gitolite-admin":
return 0
# When receiving an update from developer "joe" to the repository
# devs/joe/repo, The request name is going to be in this format:
# 2000-01-01.10.00.00_joe_devs.joe.repo.yaml
time_string = datetime.strftime(datetime.now(), "%Y-%m-%d.%H.%M.%S")
repo_name_path = repo.replace("/", ".")
request_name = time_string + "_" + user + "_" + repo_name_path + ".yaml"
request_path = os.path.join(_requests_dir, request_name)
info = {
"user": user,
"repo": repo
}
try:
yaml_info = yaml.safe_dump(info)
except Exception:
return 3
# Both the lock file and the request need to be readable and writable
# by the group, but git/gitolite impose a umask. We change it explicitly.
# Reference:
# https://stackoverflow.com/questions/11574271/git-change-
# default-umask-when-update-file
os.umask(0002)
lock_path = os.path.join(_requests_dir, ".lock")
lock = flufl.lock.Lock(lock_path, lifetime=_lock_lifetime)
# Try to acquire the lock with the defined timeout.
# We don't use "with lock" because then we can't define custom timeout.
try:
lock.lock(timeout=_lock_timeout)
except Exception:
return 4
# Try to write the file. Clean up the lock in any case.
try:
with open(request_path, "w") as stream:
stream.write(yaml_info)
except Exception:
return 5
finally:
try:
lock.unlock()
except Exception:
# This can happen if the lock expired.
# We don't care about this for now, because it shouldn't
# take so much time to write the YAML.
pass
return 0
def process_mailbox(self, mailbox):
self.set_log_context('mailbox', mailbox)
mailbox_path = self.get_mailbox_path(mailbox)
# Try to obtain a lock on the mailbox.
try:
lock = flufl.lock.Lock(lockfile=os.path.join(mailbox_path, '.bsmtp_lock'), lifetime=datetime.timedelta(minutes=15))
lock.retry_errnos = [116]
lock.lock(timeout=datetime.timedelta(seconds=5))
except flufl.lock.LockError as e:
self.log('cannot obtain lock on mailbox path {0} ({1})'.format(mailbox_path, e))
lock = None
if lock is not None and lock.is_locked:
try:
# We try not to run too often: if the last run was not succesful,
# wait at least a minute at first, doubling the time between
# consecutive runs until we run once an hour.
last = 0
now = int(time.time())
success = now
throttle_file = os.path.join(mailbox_path, '.bsmtp_run')
try:
with open(throttle_file) as tf:
r = tf.readline().split()
last = int(r[0])
success = int(r[1])
now = int(time.time())
if (last != success) and (now - last) < 3600: # last run not a success and less than an hour ago
if (
((now - last) < 60) or # unsuccesful run less than a minute ago
((now - last) < (last - success )) # last unsuccesful run less than double the amount to the last succesful run
):
# Skip this run.
return
except:
pass
mailbox_files = self.get_mailbox_files(mailbox)
mail_count = len(mailbox_files)
deliver_count = 0
tempfail_count = 0
tempfail_limit = self.config.get('bsmtp_deliver', {}).get('tempfail_limit', 10)
if mail_count > 0:
# There is email to be delivered. Get delivery details.
(domain, mailhost, port, tls_type, tls_digest_type, tls_digest) = self.query_config_table('bsmtp_delivery', mailbox)[0]
report = mailboxutil.MailboxReport(mailbox, 'rejection')
# Make a Rejected directory if it does not yet exist
rejection_dir = os.path.join(self.get_mailbox_path(mailbox, self.config.get('bsmtp_mailbox', {}).get('rejection', {}).get('folder', 'Rejected')), 'new')
if not os.path.exists(rejection_dir):
os.makedirs(rejection_dir)
# Try to connect to the mailserver, deliver all the
# mail, then exit.
try:
with delivery.Delivery(mailbox=mailbox) as d:
for (subdir, filename) in mailbox_files:
for k in ('id', 'from', 'to', 'size', 'message_id', 'queue_id'):
self.del_log_context(k)
source_subpath = os.path.join(subdir, filename)
source_path = os.path.join(mailbox_path, source_subpath)
self.set_log_context('message_file', source_subpath)
with open(source_path) as mail_file:
try:
self.log('starting delivery', priority=syslog.LOG_DEBUG)
d.deliver(mail_file)
os.unlink(mail_file.name)
deliver_count = deliver_count + 1
tempfail_count = 0
except delivery.DeliveryError as e:
if e.fatal:
self.log('rejected ({0})'.format(e))
report.add_email(
sender=e.sender,
recipient=e.recipient,
message_path=source_subpath,
extra='{0} {1}'.format(e.code, e.message)
)
os.rename(
source_path,
os.path.join(rejection_dir, filename)
)
# Just lower the tempfail
# counter for a permanent error,
# but don't reset it to 0.
if tempfail_count > 0:
tempfail_count = tempfail_count - 1
else:
tempfail_count = tempfail_count + 1
self.log('tempfail {0} ({1})'.format(tempfail_count, e))
if tempfail_count >= tempfail_limit:
self.log('giving up after {0} subsequent tempfail responses'.format(tempfail_count))
break
lock.refresh()
self.del_log_context('message_file')
except socket.error as e:
self.log('socket error ({0})'.format(e))
pass
except smtplib.SMTPConnectError as e:
self.log('SMTP connection error ({0})'.format(e))
pass
# Did we deliver any email?
if deliver_count > 0:
# Remove the maildirsize file if we're configured to do
# so. This triggers quota recalculating by the mailserver.
if self.config.get('bsmtp_mailbox', {}).get('remove_maildirsize', False):
try:
os.unlink(os.path.join(mailbox_path, 'maildirsize'))
except OSError:
pass
# Update time of last succesful delivery
success = int(time.time())
# Send the report if there is something in it.
report.send()
else: # empty mailbox, always succesful
success = int(time.time())
# Record the time of this run.
try:
with open(throttle_file, 'w') as tf:
tf.write("{0} {1}\n".format(int(time.time()), success))
except:
pass
except Exception as e:
self.log('caught exception {0}'.format(e), priority=syslog.LOG_ERR)
raise
finally:
lock.unlock()
def release_lock(lock):
"Release a lock currently held by Instant."
if lock.is_locked:
hostname, pid, lockname = lock.details
instant_debug("Releasing lock %s." % (lockname))
lock.unlock()