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