def release(self):
"""Releases the lock, that was acquired with the same object.
.. note::
If you want to release a lock that you acquired in a different place you have two choices:
* Use ``Lock("name", id=id_from_other_place).release()``
* Use ``Lock("name").reset()``
"""
if self._lock_renewal_thread is not None:
self._stop_lock_renewer()
log_info("Releasing %s." % self._name)
error = _eval_script(self._client,
UNLOCK_SCRIPT,
self._name,
self._signal,
self._signal_expire,
args=(self._id, ))
if error == 1:
raise NotAcquired(
"Lock %s is not acquired or it already expired." % self._name)
elif error:
raise RuntimeError(
"Unsupported error code %s from EXTEND script." % error)
def loop():
identifier1 = str(uuid.uuid1())
conn = redis.Redis(connection_pool=redis_connection.redis_pool)
response = conn.client_list()
log_info('sbsb' + str(response))
global lock
lock = Lock(conn, "my_lock1", expire=10, id=identifier1, auto_renewal=True)
val = conn.get("my_lock1")
print(str(val))
pid = os.fork()
if pid == 0:
while True:
w1()
else:
print("Create the process w1")
pid = os.fork()
identifier2 = str(uuid.uuid1())
print(identifier1 + ":" + identifier2)
nlock = Lock(conn,
"my_lock1",
expire=10,
id=identifier2,
auto_renewal=True)
if pid == 0:
while True:
w2(nlock)
else:
print("Create the process w2")
def _eval_script(redis, script_id, *keys, **kwargs):
"""Tries to call ``EVALSHA`` with the `hash` and then, if it fails, calls
regular ``EVAL`` with the `script`.
"""
args = kwargs.pop('args', ())
if kwargs:
raise TypeError("Unexpected keyword arguments %s" % kwargs.keys())
try:
return redis.evalsha(SCRIPTS[script_id], len(keys), *keys + args)
except NoScriptError:
log_info("%s not cached." % SCRIPTS[script_id + 2])
return redis.eval(SCRIPTS[script_id + 1], len(keys), *keys + args)
def _start_lock_renewer(self):
"""
Starts the lock refresher thread.
"""
if self._lock_renewal_thread is not None:
raise AlreadyStarted("Lock refresh thread already started")
log_info("Starting thread to refresh lock every %s seconds" %
self._lock_renewal_interval)
self._lock_renewal_stop = threading.Event()
self._lock_renewal_thread = threading.Thread(
group=None,
target=self._lock_renewer,
kwargs={
'lockref': weakref.ref(self),
'interval': self._lock_renewal_interval,
'stop': self._lock_renewal_stop
})
self._lock_renewal_thread.setDaemon(True)
self._lock_renewal_thread.start()
def w1():
global lock
if lock._held:
log_info('held')
if lock.locked():
log_info('lock live')
lock.acquire()
print("w1 get the lock")
print(lock._client.get('lock:my_lock1'))
time.sleep(20)
if lock._lock_renewal_thread is not None:
log_info('fffgggg')
if lock._lock_renewal_thread.isAlive():
log_info('renew fail')
lock.release()
print("w1 end")
def _stop_lock_renewer(self):
"""
Stop the lock renewer.
This signals the renewal thread and waits for its exit.
"""
if self._lock_renewal_thread is None or not self._lock_renewal_thread.is_alive(
):
return
log_info("Signalling the lock refresher to stop")
self._lock_renewal_stop.set()
log_info("wchao")
log_info(self._client.get(self._name))
self._lock_renewal_thread.join()
self._lock_renewal_thread = None
log_info("Lock refresher has stopped")
def _lock_renewer(lockref, interval, stop):
"""
Renew the lock key in redis every `interval` seconds for as long
as `self._lock_renewal_thread.should_exit` is False.
"""
while True:
res = stop.wait(timeout=interval)
log_info(res)
if res:
break
log_info("Refreshing lock")
lock = lockref()
if lock is None:
log_info("The lock no longer exists, "
"stopping lock refreshing")
break
lock.extend(expire=lock._expire)
del lock
log_info("Exit requested, stopping lock refreshing")
def acquire(self, blocking=True, timeout=None):
"""
:param blocking:
Boolean value specifying whether lock should be blocking or not.
:param timeout:
An integer value specifying the maximum number of seconds to block.
"""
log_info("Getting %s ..." % self._name)
if self._held:
raise AlreadyAcquired("Already acquired from this Lock instance.")
if not blocking and timeout is not None:
raise TimeoutNotUsable("Timeout cannot be used if blocking=False")
timeout = timeout if timeout is None else int(timeout)
if timeout is not None and timeout <= 0:
raise InvalidTimeout(
"Timeout (%d) cannot be less than or equal to 0" % timeout)
if timeout and self._expire and timeout > self._expire:
raise TimeoutTooLarge(
"Timeout (%d) cannot be greater than expire (%d)" %
(timeout, self._expire))
busy = True
blpop_timeout = timeout or self._expire or 0
timed_out = False
while busy:
busy = not self._client.set(
self._name, self._id, nx=True, ex=self._expire)
if busy:
if timed_out:
return False
elif blocking:
timed_out = not self._client.blpop(
self._signal, blpop_timeout) and timeout
else:
log_info("Failed to get %s." % self._name)
return False
log_info("Got lock for %s." % self._name)
if self._lock_renewal_interval is not None:
self._start_lock_renewer()
return True
import redis
from redis_notes.common.log import log_info
def _set_up_redis_instance():
instance = redis.ConnectionPool(host='localhost', port=6379, decode_responses=True)
return instance
redis_pool = None
try:
redis_pool = _set_up_redis_instance()
print str(redis_pool)+"wwwwww"
print redis_pool.ping()
response = redis_pool.client_list()
log_info('sbsb' + str(response))
log_info(redis_pool)
except:
print "fail initiating redis instance"
try:
conn = redis.Redis(host='localhost', port=6379, decode_responses=True)
response = conn.client_list()
log_info('hbhb'+str(response))
except redis.ConnectionError:
log_info('connection sbsbsb')
