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@@ -1,13 +1,14 b'' | |||||
1 | import sys |
|
1 | ||
2 | import threading |
|
2 | import threading | |
3 | import weakref |
|
3 | import weakref | |
4 | from base64 import b64encode |
|
4 | from base64 import b64encode | |
5 | from logging import getLogger |
|
5 | from logging import getLogger | |
6 | from os import urandom |
|
6 | from os import urandom | |
|
7 | from typing import Union | |||
7 |
|
8 | |||
8 | from redis import StrictRedis |
|
9 | from redis import StrictRedis | |
9 |
|
10 | |||
10 |
__version__ = ' |
|
11 | __version__ = '4.0.0' | |
11 |
|
12 | |||
12 | loggers = { |
|
13 | loggers = { | |
13 | k: getLogger("vcsserver." + ".".join((__name__, k))) |
|
14 | k: getLogger("vcsserver." + ".".join((__name__, k))) | |
@@ -105,11 +106,15 b' class Lock(object):' | |||||
105 | """ |
|
106 | """ | |
106 | A Lock context manager implemented via redis SETNX/BLPOP. |
|
107 | A Lock context manager implemented via redis SETNX/BLPOP. | |
107 | """ |
|
108 | """ | |
|
109 | ||||
108 | unlock_script = None |
|
110 | unlock_script = None | |
109 | extend_script = None |
|
111 | extend_script = None | |
110 | reset_script = None |
|
112 | reset_script = None | |
111 | reset_all_script = None |
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113 | reset_all_script = None | |
112 |
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114 | |||
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115 | _lock_renewal_interval: float | |||
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116 | _lock_renewal_thread: Union[threading.Thread, None] | |||
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117 | ||||
113 | def __init__(self, redis_client, name, expire=None, id=None, auto_renewal=False, strict=True, signal_expire=1000): |
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118 | def __init__(self, redis_client, name, expire=None, id=None, auto_renewal=False, strict=True, signal_expire=1000): | |
114 | """ |
|
119 | """ | |
115 | :param redis_client: |
|
120 | :param redis_client: | |
@@ -166,7 +171,7 b' class Lock(object):' | |||||
166 | elif isinstance(id, text_type): |
|
171 | elif isinstance(id, text_type): | |
167 | self._id = id |
|
172 | self._id = id | |
168 | else: |
|
173 | else: | |
169 |
raise TypeError("Incorrect type for `id`. Must be bytes/str not |
|
174 | raise TypeError(f"Incorrect type for `id`. Must be bytes/str not {type(id)}.") | |
170 | self._name = 'lock:' + name |
|
175 | self._name = 'lock:' + name | |
171 | self._signal = 'lock-signal:' + name |
|
176 | self._signal = 'lock-signal:' + name | |
172 | self._lock_renewal_interval = (float(expire) * 2 / 3 |
|
177 | self._lock_renewal_interval = (float(expire) * 2 / 3 | |
@@ -180,11 +185,11 b' class Lock(object):' | |||||
180 | def register_scripts(cls, redis_client): |
|
185 | def register_scripts(cls, redis_client): | |
181 | global reset_all_script |
|
186 | global reset_all_script | |
182 | if reset_all_script is None: |
|
187 | if reset_all_script is None: | |
183 | reset_all_script = redis_client.register_script(RESET_ALL_SCRIPT) |
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|||
184 | cls.unlock_script = redis_client.register_script(UNLOCK_SCRIPT) |
|
188 | cls.unlock_script = redis_client.register_script(UNLOCK_SCRIPT) | |
185 | cls.extend_script = redis_client.register_script(EXTEND_SCRIPT) |
|
189 | cls.extend_script = redis_client.register_script(EXTEND_SCRIPT) | |
186 | cls.reset_script = redis_client.register_script(RESET_SCRIPT) |
|
190 | cls.reset_script = redis_client.register_script(RESET_SCRIPT) | |
187 | cls.reset_all_script = redis_client.register_script(RESET_ALL_SCRIPT) |
|
191 | cls.reset_all_script = redis_client.register_script(RESET_ALL_SCRIPT) | |
|
192 | reset_all_script = redis_client.register_script(RESET_ALL_SCRIPT) | |||
188 |
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193 | |||
189 | @property |
|
194 | @property | |
190 | def _held(self): |
|
195 | def _held(self): | |
@@ -219,7 +224,7 b' class Lock(object):' | |||||
219 |
|
224 | |||
220 | if self._held: |
|
225 | if self._held: | |
221 | owner_id = self.get_owner_id() |
|
226 | owner_id = self.get_owner_id() | |
222 |
raise AlreadyAcquired( |
|
227 | raise AlreadyAcquired("Already acquired from this Lock instance. Lock id: {}".format(owner_id)) | |
223 |
|
228 | |||
224 | if not blocking and timeout is not None: |
|
229 | if not blocking and timeout is not None: | |
225 | raise TimeoutNotUsable("Timeout cannot be used if blocking=False") |
|
230 | raise TimeoutNotUsable("Timeout cannot be used if blocking=False") | |
@@ -227,10 +232,10 b' class Lock(object):' | |||||
227 | if timeout: |
|
232 | if timeout: | |
228 | timeout = int(timeout) |
|
233 | timeout = int(timeout) | |
229 | if timeout < 0: |
|
234 | if timeout < 0: | |
230 |
raise InvalidTimeout("Timeout ( |
|
235 | raise InvalidTimeout(f"Timeout ({timeout}) cannot be less than or equal to 0") | |
231 |
|
236 | |||
232 | if self._expire and not self._lock_renewal_interval and timeout > self._expire: |
|
237 | if self._expire and not self._lock_renewal_interval and timeout > self._expire: | |
233 |
raise TimeoutTooLarge("Timeout ( |
|
238 | raise TimeoutTooLarge(f"Timeout ({timeout}) cannot be greater than expire ({self._expire})") | |
234 |
|
239 | |||
235 | busy = True |
|
240 | busy = True | |
236 | blpop_timeout = timeout or self._expire or 0 |
|
241 | blpop_timeout = timeout or self._expire or 0 | |
@@ -243,16 +248,17 b' class Lock(object):' | |||||
243 | elif blocking: |
|
248 | elif blocking: | |
244 | timed_out = not self._client.blpop(self._signal, blpop_timeout) and timeout |
|
249 | timed_out = not self._client.blpop(self._signal, blpop_timeout) and timeout | |
245 | else: |
|
250 | else: | |
246 |
logger.warning("Failed to |
|
251 | logger.warning("Failed to acquire Lock(%r).", self._name) | |
247 | return False |
|
252 | return False | |
248 |
|
253 | |||
249 |
logger.debug(" |
|
254 | logger.debug("Acquired Lock(%r).", self._name) | |
250 | if self._lock_renewal_interval is not None: |
|
255 | if self._lock_renewal_interval is not None: | |
251 | self._start_lock_renewer() |
|
256 | self._start_lock_renewer() | |
252 | return True |
|
257 | return True | |
253 |
|
258 | |||
254 | def extend(self, expire=None): |
|
259 | def extend(self, expire=None): | |
255 | """Extends expiration time of the lock. |
|
260 | """ | |
|
261 | Extends expiration time of the lock. | |||
256 |
|
262 | |||
257 | :param expire: |
|
263 | :param expire: | |
258 | New expiration time. If ``None`` - `expire` provided during |
|
264 | New expiration time. If ``None`` - `expire` provided during | |
@@ -272,29 +278,29 b' class Lock(object):' | |||||
272 |
|
278 | |||
273 | error = self.extend_script(client=self._client, keys=(self._name, self._signal), args=(self._id, expire)) |
|
279 | error = self.extend_script(client=self._client, keys=(self._name, self._signal), args=(self._id, expire)) | |
274 | if error == 1: |
|
280 | if error == 1: | |
275 |
raise NotAcquired("Lock |
|
281 | raise NotAcquired(f"Lock {self._name} is not acquired or it already expired.") | |
276 | elif error == 2: |
|
282 | elif error == 2: | |
277 |
raise NotExpirable("Lock |
|
283 | raise NotExpirable(f"Lock {self._name} has no assigned expiration time") | |
278 | elif error: |
|
284 | elif error: | |
279 |
raise RuntimeError("Unsupported error code |
|
285 | raise RuntimeError(f"Unsupported error code {error} from EXTEND script") | |
280 |
|
286 | |||
281 | @staticmethod |
|
287 | @staticmethod | |
282 | def _lock_renewer(lockref, interval, stop): |
|
288 | def _lock_renewer(name, lockref, interval, stop): | |
283 | """ |
|
289 | """ | |
284 | Renew the lock key in redis every `interval` seconds for as long |
|
290 | Renew the lock key in redis every `interval` seconds for as long | |
285 | as `self._lock_renewal_thread.should_exit` is False. |
|
291 | as `self._lock_renewal_thread.should_exit` is False. | |
286 | """ |
|
292 | """ | |
287 | while not stop.wait(timeout=interval): |
|
293 | while not stop.wait(timeout=interval): | |
288 |
loggers["refresh.thread.start"].debug("Refreshing |
|
294 | loggers["refresh.thread.start"].debug("Refreshing Lock(%r).", name) | |
289 | lock = lockref() |
|
295 | lock: "Lock" = lockref() | |
290 | if lock is None: |
|
296 | if lock is None: | |
291 | loggers["refresh.thread.stop"].debug( |
|
297 | loggers["refresh.thread.stop"].debug( | |
292 | "The lock no longer exists, stopping lock refreshing" |
|
298 | "Stopping loop because Lock(%r) was garbage collected.", name | |
293 | ) |
|
299 | ) | |
294 | break |
|
300 | break | |
295 | lock.extend(expire=lock._expire) |
|
301 | lock.extend(expire=lock._expire) | |
296 | del lock |
|
302 | del lock | |
297 |
loggers["refresh.thread.exit"].debug("Exit |
|
303 | loggers["refresh.thread.exit"].debug("Exiting renewal thread for Lock(%r).", name) | |
298 |
|
304 | |||
299 | def _start_lock_renewer(self): |
|
305 | def _start_lock_renewer(self): | |
300 | """ |
|
306 | """ | |
@@ -304,18 +310,21 b' class Lock(object):' | |||||
304 | raise AlreadyStarted("Lock refresh thread already started") |
|
310 | raise AlreadyStarted("Lock refresh thread already started") | |
305 |
|
311 | |||
306 | loggers["refresh.start"].debug( |
|
312 | loggers["refresh.start"].debug( | |
307 |
"Starting thread |
|
313 | "Starting renewal thread for Lock(%r). Refresh interval: %s seconds.", | |
308 | self._lock_renewal_interval |
|
314 | self._name, self._lock_renewal_interval | |
309 | ) |
|
315 | ) | |
310 | self._lock_renewal_stop = threading.Event() |
|
316 | self._lock_renewal_stop = threading.Event() | |
311 | self._lock_renewal_thread = threading.Thread( |
|
317 | self._lock_renewal_thread = threading.Thread( | |
312 | group=None, |
|
318 | group=None, | |
313 | target=self._lock_renewer, |
|
319 | target=self._lock_renewer, | |
314 | kwargs={'lockref': weakref.ref(self), |
|
320 | kwargs={ | |
|
321 | 'name': self._name, | |||
|
322 | 'lockref': weakref.ref(self), | |||
315 |
|
|
323 | 'interval': self._lock_renewal_interval, | |
316 |
|
|
324 | 'stop': self._lock_renewal_stop, | |
|
325 | }, | |||
317 | ) |
|
326 | ) | |
318 |
self._lock_renewal_thread. |
|
327 | self._lock_renewal_thread.daemon = True | |
319 | self._lock_renewal_thread.start() |
|
328 | self._lock_renewal_thread.start() | |
320 |
|
329 | |||
321 | def _stop_lock_renewer(self): |
|
330 | def _stop_lock_renewer(self): | |
@@ -326,15 +335,16 b' class Lock(object):' | |||||
326 | """ |
|
335 | """ | |
327 | if self._lock_renewal_thread is None or not self._lock_renewal_thread.is_alive(): |
|
336 | if self._lock_renewal_thread is None or not self._lock_renewal_thread.is_alive(): | |
328 | return |
|
337 | return | |
329 |
loggers["refresh.shutdown"].debug("Signal |
|
338 | loggers["refresh.shutdown"].debug("Signaling renewal thread for Lock(%r) to exit.", self._name) | |
330 | self._lock_renewal_stop.set() |
|
339 | self._lock_renewal_stop.set() | |
331 | self._lock_renewal_thread.join() |
|
340 | self._lock_renewal_thread.join() | |
332 | self._lock_renewal_thread = None |
|
341 | self._lock_renewal_thread = None | |
333 |
loggers["refresh.exit"].debug(" |
|
342 | loggers["refresh.exit"].debug("Renewal thread for Lock(%r) exited.", self._name) | |
334 |
|
343 | |||
335 | def __enter__(self): |
|
344 | def __enter__(self): | |
336 | acquired = self.acquire(blocking=True) |
|
345 | acquired = self.acquire(blocking=True) | |
337 | assert acquired, "Lock wasn't acquired, but blocking=True" |
|
346 | if not acquired: | |
|
347 | raise AssertionError(f"Lock({self._name}) wasn't acquired, but blocking=True was used!") | |||
338 | return self |
|
348 | return self | |
339 |
|
349 | |||
340 | def __exit__(self, exc_type=None, exc_value=None, traceback=None): |
|
350 | def __exit__(self, exc_type=None, exc_value=None, traceback=None): | |
@@ -352,12 +362,12 b' class Lock(object):' | |||||
352 | """ |
|
362 | """ | |
353 | if self._lock_renewal_thread is not None: |
|
363 | if self._lock_renewal_thread is not None: | |
354 | self._stop_lock_renewer() |
|
364 | self._stop_lock_renewer() | |
355 | loggers["release"].debug("Releasing %r.", self._name) |
|
365 | loggers["release"].debug("Releasing Lock(%r).", self._name) | |
356 | error = self.unlock_script(client=self._client, keys=(self._name, self._signal), args=(self._id, self._signal_expire)) |
|
366 | error = self.unlock_script(client=self._client, keys=(self._name, self._signal), args=(self._id, self._signal_expire)) | |
357 | if error == 1: |
|
367 | if error == 1: | |
358 |
raise NotAcquired("Lock |
|
368 | raise NotAcquired(f"Lock({self._name}) is not acquired or it already expired.") | |
359 | elif error: |
|
369 | elif error: | |
360 |
raise RuntimeError("Unsupported error code |
|
370 | raise RuntimeError(f"Unsupported error code {error} from EXTEND script.") | |
361 |
|
371 | |||
362 | def locked(self): |
|
372 | def locked(self): | |
363 | """ |
|
373 | """ |
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