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@@ -1,384 +1,394 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("rhodecode." + ".".join((__name__, k))) |
|
14 | k: getLogger("rhodecode." + ".".join((__name__, k))) | |
14 | for k in [ |
|
15 | for k in [ | |
15 | "acquire", |
|
16 | "acquire", | |
16 | "refresh.thread.start", |
|
17 | "refresh.thread.start", | |
17 | "refresh.thread.stop", |
|
18 | "refresh.thread.stop", | |
18 | "refresh.thread.exit", |
|
19 | "refresh.thread.exit", | |
19 | "refresh.start", |
|
20 | "refresh.start", | |
20 | "refresh.shutdown", |
|
21 | "refresh.shutdown", | |
21 | "refresh.exit", |
|
22 | "refresh.exit", | |
22 | "release", |
|
23 | "release", | |
23 | ] |
|
24 | ] | |
24 | } |
|
25 | } | |
25 |
|
26 | |||
26 | text_type = str |
|
27 | text_type = str | |
27 | binary_type = bytes |
|
28 | binary_type = bytes | |
28 |
|
29 | |||
29 |
|
30 | |||
30 | # Check if the id match. If not, return an error code. |
|
31 | # Check if the id match. If not, return an error code. | |
31 | UNLOCK_SCRIPT = b""" |
|
32 | UNLOCK_SCRIPT = b""" | |
32 | if redis.call("get", KEYS[1]) ~= ARGV[1] then |
|
33 | if redis.call("get", KEYS[1]) ~= ARGV[1] then | |
33 | return 1 |
|
34 | return 1 | |
34 | else |
|
35 | else | |
35 | redis.call("del", KEYS[2]) |
|
36 | redis.call("del", KEYS[2]) | |
36 | redis.call("lpush", KEYS[2], 1) |
|
37 | redis.call("lpush", KEYS[2], 1) | |
37 | redis.call("pexpire", KEYS[2], ARGV[2]) |
|
38 | redis.call("pexpire", KEYS[2], ARGV[2]) | |
38 | redis.call("del", KEYS[1]) |
|
39 | redis.call("del", KEYS[1]) | |
39 | return 0 |
|
40 | return 0 | |
40 | end |
|
41 | end | |
41 | """ |
|
42 | """ | |
42 |
|
43 | |||
43 | # Covers both cases when key doesn't exist and doesn't equal to lock's id |
|
44 | # Covers both cases when key doesn't exist and doesn't equal to lock's id | |
44 | EXTEND_SCRIPT = b""" |
|
45 | EXTEND_SCRIPT = b""" | |
45 | if redis.call("get", KEYS[1]) ~= ARGV[1] then |
|
46 | if redis.call("get", KEYS[1]) ~= ARGV[1] then | |
46 | return 1 |
|
47 | return 1 | |
47 | elseif redis.call("ttl", KEYS[1]) < 0 then |
|
48 | elseif redis.call("ttl", KEYS[1]) < 0 then | |
48 | return 2 |
|
49 | return 2 | |
49 | else |
|
50 | else | |
50 | redis.call("expire", KEYS[1], ARGV[2]) |
|
51 | redis.call("expire", KEYS[1], ARGV[2]) | |
51 | return 0 |
|
52 | return 0 | |
52 | end |
|
53 | end | |
53 | """ |
|
54 | """ | |
54 |
|
55 | |||
55 | RESET_SCRIPT = b""" |
|
56 | RESET_SCRIPT = b""" | |
56 | redis.call('del', KEYS[2]) |
|
57 | redis.call('del', KEYS[2]) | |
57 | redis.call('lpush', KEYS[2], 1) |
|
58 | redis.call('lpush', KEYS[2], 1) | |
58 | redis.call('pexpire', KEYS[2], ARGV[2]) |
|
59 | redis.call('pexpire', KEYS[2], ARGV[2]) | |
59 | return redis.call('del', KEYS[1]) |
|
60 | return redis.call('del', KEYS[1]) | |
60 | """ |
|
61 | """ | |
61 |
|
62 | |||
62 | RESET_ALL_SCRIPT = b""" |
|
63 | RESET_ALL_SCRIPT = b""" | |
63 | local locks = redis.call('keys', 'lock:*') |
|
64 | local locks = redis.call('keys', 'lock:*') | |
64 | local signal |
|
65 | local signal | |
65 | for _, lock in pairs(locks) do |
|
66 | for _, lock in pairs(locks) do | |
66 | signal = 'lock-signal:' .. string.sub(lock, 6) |
|
67 | signal = 'lock-signal:' .. string.sub(lock, 6) | |
67 | redis.call('del', signal) |
|
68 | redis.call('del', signal) | |
68 | redis.call('lpush', signal, 1) |
|
69 | redis.call('lpush', signal, 1) | |
69 | redis.call('expire', signal, 1) |
|
70 | redis.call('expire', signal, 1) | |
70 | redis.call('del', lock) |
|
71 | redis.call('del', lock) | |
71 | end |
|
72 | end | |
72 | return #locks |
|
73 | return #locks | |
73 | """ |
|
74 | """ | |
74 |
|
75 | |||
75 |
|
76 | |||
76 | class AlreadyAcquired(RuntimeError): |
|
77 | class AlreadyAcquired(RuntimeError): | |
77 | pass |
|
78 | pass | |
78 |
|
79 | |||
79 |
|
80 | |||
80 | class NotAcquired(RuntimeError): |
|
81 | class NotAcquired(RuntimeError): | |
81 | pass |
|
82 | pass | |
82 |
|
83 | |||
83 |
|
84 | |||
84 | class AlreadyStarted(RuntimeError): |
|
85 | class AlreadyStarted(RuntimeError): | |
85 | pass |
|
86 | pass | |
86 |
|
87 | |||
87 |
|
88 | |||
88 | class TimeoutNotUsable(RuntimeError): |
|
89 | class TimeoutNotUsable(RuntimeError): | |
89 | pass |
|
90 | pass | |
90 |
|
91 | |||
91 |
|
92 | |||
92 | class InvalidTimeout(RuntimeError): |
|
93 | class InvalidTimeout(RuntimeError): | |
93 | pass |
|
94 | pass | |
94 |
|
95 | |||
95 |
|
96 | |||
96 | class TimeoutTooLarge(RuntimeError): |
|
97 | class TimeoutTooLarge(RuntimeError): | |
97 | pass |
|
98 | pass | |
98 |
|
99 | |||
99 |
|
100 | |||
100 | class NotExpirable(RuntimeError): |
|
101 | class NotExpirable(RuntimeError): | |
101 | pass |
|
102 | pass | |
102 |
|
103 | |||
103 |
|
104 | |||
104 | class Lock(object): |
|
105 | 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 |
|
113 | reset_all_script = None | |
112 |
|
114 | |||
|
115 | _lock_renewal_interval: float | |||
|
116 | _lock_renewal_thread: Union[threading.Thread, None] | |||
|
117 | ||||
113 | def __init__(self, redis_client, name, expire=None, id=None, auto_renewal=False, strict=True, signal_expire=1000): |
|
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: | |
116 | An instance of :class:`~StrictRedis`. |
|
121 | An instance of :class:`~StrictRedis`. | |
117 | :param name: |
|
122 | :param name: | |
118 | The name (redis key) the lock should have. |
|
123 | The name (redis key) the lock should have. | |
119 | :param expire: |
|
124 | :param expire: | |
120 | The lock expiry time in seconds. If left at the default (None) |
|
125 | The lock expiry time in seconds. If left at the default (None) | |
121 | the lock will not expire. |
|
126 | the lock will not expire. | |
122 | :param id: |
|
127 | :param id: | |
123 | The ID (redis value) the lock should have. A random value is |
|
128 | The ID (redis value) the lock should have. A random value is | |
124 | generated when left at the default. |
|
129 | generated when left at the default. | |
125 |
|
130 | |||
126 | Note that if you specify this then the lock is marked as "held". Acquires |
|
131 | Note that if you specify this then the lock is marked as "held". Acquires | |
127 | won't be possible. |
|
132 | won't be possible. | |
128 | :param auto_renewal: |
|
133 | :param auto_renewal: | |
129 | If set to ``True``, Lock will automatically renew the lock so that it |
|
134 | If set to ``True``, Lock will automatically renew the lock so that it | |
130 | doesn't expire for as long as the lock is held (acquire() called |
|
135 | doesn't expire for as long as the lock is held (acquire() called | |
131 | or running in a context manager). |
|
136 | or running in a context manager). | |
132 |
|
137 | |||
133 | Implementation note: Renewal will happen using a daemon thread with |
|
138 | Implementation note: Renewal will happen using a daemon thread with | |
134 | an interval of ``expire*2/3``. If wishing to use a different renewal |
|
139 | an interval of ``expire*2/3``. If wishing to use a different renewal | |
135 | time, subclass Lock, call ``super().__init__()`` then set |
|
140 | time, subclass Lock, call ``super().__init__()`` then set | |
136 | ``self._lock_renewal_interval`` to your desired interval. |
|
141 | ``self._lock_renewal_interval`` to your desired interval. | |
137 | :param strict: |
|
142 | :param strict: | |
138 | If set ``True`` then the ``redis_client`` needs to be an instance of ``redis.StrictRedis``. |
|
143 | If set ``True`` then the ``redis_client`` needs to be an instance of ``redis.StrictRedis``. | |
139 | :param signal_expire: |
|
144 | :param signal_expire: | |
140 | Advanced option to override signal list expiration in milliseconds. Increase it for very slow clients. Default: ``1000``. |
|
145 | Advanced option to override signal list expiration in milliseconds. Increase it for very slow clients. Default: ``1000``. | |
141 | """ |
|
146 | """ | |
142 | if strict and not isinstance(redis_client, StrictRedis): |
|
147 | if strict and not isinstance(redis_client, StrictRedis): | |
143 | raise ValueError("redis_client must be instance of StrictRedis. " |
|
148 | raise ValueError("redis_client must be instance of StrictRedis. " | |
144 | "Use strict=False if you know what you're doing.") |
|
149 | "Use strict=False if you know what you're doing.") | |
145 | if auto_renewal and expire is None: |
|
150 | if auto_renewal and expire is None: | |
146 | raise ValueError("Expire may not be None when auto_renewal is set") |
|
151 | raise ValueError("Expire may not be None when auto_renewal is set") | |
147 |
|
152 | |||
148 | self._client = redis_client |
|
153 | self._client = redis_client | |
149 |
|
154 | |||
150 | if expire: |
|
155 | if expire: | |
151 | expire = int(expire) |
|
156 | expire = int(expire) | |
152 | if expire < 0: |
|
157 | if expire < 0: | |
153 | raise ValueError("A negative expire is not acceptable.") |
|
158 | raise ValueError("A negative expire is not acceptable.") | |
154 | else: |
|
159 | else: | |
155 | expire = None |
|
160 | expire = None | |
156 | self._expire = expire |
|
161 | self._expire = expire | |
157 |
|
162 | |||
158 | self._signal_expire = signal_expire |
|
163 | self._signal_expire = signal_expire | |
159 | if id is None: |
|
164 | if id is None: | |
160 | self._id = b64encode(urandom(18)).decode('ascii') |
|
165 | self._id = b64encode(urandom(18)).decode('ascii') | |
161 | elif isinstance(id, binary_type): |
|
166 | elif isinstance(id, binary_type): | |
162 | try: |
|
167 | try: | |
163 | self._id = id.decode('ascii') |
|
168 | self._id = id.decode('ascii') | |
164 | except UnicodeDecodeError: |
|
169 | except UnicodeDecodeError: | |
165 | self._id = b64encode(id).decode('ascii') |
|
170 | self._id = b64encode(id).decode('ascii') | |
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 | |
173 | if auto_renewal |
|
178 | if auto_renewal | |
174 | else None) |
|
179 | else None) | |
175 | self._lock_renewal_thread = None |
|
180 | self._lock_renewal_thread = None | |
176 |
|
181 | |||
177 | self.register_scripts(redis_client) |
|
182 | self.register_scripts(redis_client) | |
178 |
|
183 | |||
179 | @classmethod |
|
184 | @classmethod | |
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) |
|
|||
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 |
|
193 | |||
189 | @property |
|
194 | @property | |
190 | def _held(self): |
|
195 | def _held(self): | |
191 | return self.id == self.get_owner_id() |
|
196 | return self.id == self.get_owner_id() | |
192 |
|
197 | |||
193 | def reset(self): |
|
198 | def reset(self): | |
194 | """ |
|
199 | """ | |
195 | Forcibly deletes the lock. Use this with care. |
|
200 | Forcibly deletes the lock. Use this with care. | |
196 | """ |
|
201 | """ | |
197 | self.reset_script(client=self._client, keys=(self._name, self._signal), args=(self.id, self._signal_expire)) |
|
202 | self.reset_script(client=self._client, keys=(self._name, self._signal), args=(self.id, self._signal_expire)) | |
198 |
|
203 | |||
199 | @property |
|
204 | @property | |
200 | def id(self): |
|
205 | def id(self): | |
201 | return self._id |
|
206 | return self._id | |
202 |
|
207 | |||
203 | def get_owner_id(self): |
|
208 | def get_owner_id(self): | |
204 | owner_id = self._client.get(self._name) |
|
209 | owner_id = self._client.get(self._name) | |
205 | if isinstance(owner_id, binary_type): |
|
210 | if isinstance(owner_id, binary_type): | |
206 | owner_id = owner_id.decode('ascii', 'replace') |
|
211 | owner_id = owner_id.decode('ascii', 'replace') | |
207 | return owner_id |
|
212 | return owner_id | |
208 |
|
213 | |||
209 | def acquire(self, blocking=True, timeout=None): |
|
214 | def acquire(self, blocking=True, timeout=None): | |
210 | """ |
|
215 | """ | |
211 | :param blocking: |
|
216 | :param blocking: | |
212 | Boolean value specifying whether lock should be blocking or not. |
|
217 | Boolean value specifying whether lock should be blocking or not. | |
213 | :param timeout: |
|
218 | :param timeout: | |
214 | An integer value specifying the maximum number of seconds to block. |
|
219 | An integer value specifying the maximum number of seconds to block. | |
215 | """ |
|
220 | """ | |
216 | logger = loggers["acquire"] |
|
221 | logger = loggers["acquire"] | |
217 |
|
222 | |||
218 | logger.debug("Getting blocking: %s acquire on %r ...", blocking, self._name) |
|
223 | logger.debug("Getting blocking: %s acquire on %r ...", blocking, self._name) | |
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("Already acquired from this Lock instance. Lock id: {}".format(owner_id)) |
|
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") | |
226 |
|
231 | |||
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 | |
237 | timed_out = False |
|
242 | timed_out = False | |
238 | while busy: |
|
243 | while busy: | |
239 | busy = not self._client.set(self._name, self._id, nx=True, ex=self._expire) |
|
244 | busy = not self._client.set(self._name, self._id, nx=True, ex=self._expire) | |
240 | if busy: |
|
245 | if busy: | |
241 | if timed_out: |
|
246 | if timed_out: | |
242 | return False |
|
247 | return False | |
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 | |
259 | lock initialization will be taken. |
|
265 | lock initialization will be taken. | |
260 | """ |
|
266 | """ | |
261 | if expire: |
|
267 | if expire: | |
262 | expire = int(expire) |
|
268 | expire = int(expire) | |
263 | if expire < 0: |
|
269 | if expire < 0: | |
264 | raise ValueError("A negative expire is not acceptable.") |
|
270 | raise ValueError("A negative expire is not acceptable.") | |
265 | elif self._expire is not None: |
|
271 | elif self._expire is not None: | |
266 | expire = self._expire |
|
272 | expire = self._expire | |
267 | else: |
|
273 | else: | |
268 | raise TypeError( |
|
274 | raise TypeError( | |
269 | "To extend a lock 'expire' must be provided as an " |
|
275 | "To extend a lock 'expire' must be provided as an " | |
270 | "argument to extend() method or at initialization time." |
|
276 | "argument to extend() method or at initialization time." | |
271 | ) |
|
277 | ) | |
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 | """ | |
301 | Starts the lock refresher thread. |
|
307 | Starts the lock refresher thread. | |
302 | """ |
|
308 | """ | |
303 | if self._lock_renewal_thread is not None: |
|
309 | if self._lock_renewal_thread is not None: | |
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): | |
322 | """ |
|
331 | """ | |
323 | Stop the lock renewer. |
|
332 | Stop the lock renewer. | |
324 |
|
333 | |||
325 | This signals the renewal thread and waits for its exit. |
|
334 | This signals the renewal thread and waits for its exit. | |
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): | |
341 | self.release() |
|
351 | self.release() | |
342 |
|
352 | |||
343 | def release(self): |
|
353 | def release(self): | |
344 | """Releases the lock, that was acquired with the same object. |
|
354 | """Releases the lock, that was acquired with the same object. | |
345 |
|
355 | |||
346 | .. note:: |
|
356 | .. note:: | |
347 |
|
357 | |||
348 | If you want to release a lock that you acquired in a different place you have two choices: |
|
358 | If you want to release a lock that you acquired in a different place you have two choices: | |
349 |
|
359 | |||
350 | * Use ``Lock("name", id=id_from_other_place).release()`` |
|
360 | * Use ``Lock("name", id=id_from_other_place).release()`` | |
351 | * Use ``Lock("name").reset()`` |
|
361 | * Use ``Lock("name").reset()`` | |
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 | """ | |
364 | Return true if the lock is acquired. |
|
374 | Return true if the lock is acquired. | |
365 |
|
375 | |||
366 | Checks that lock with same name already exists. This method returns true, even if |
|
376 | Checks that lock with same name already exists. This method returns true, even if | |
367 | lock have another id. |
|
377 | lock have another id. | |
368 | """ |
|
378 | """ | |
369 | return self._client.exists(self._name) == 1 |
|
379 | return self._client.exists(self._name) == 1 | |
370 |
|
380 | |||
371 |
|
381 | |||
372 | reset_all_script = None |
|
382 | reset_all_script = None | |
373 |
|
383 | |||
374 |
|
384 | |||
375 | def reset_all(redis_client): |
|
385 | def reset_all(redis_client): | |
376 | """ |
|
386 | """ | |
377 | Forcibly deletes all locks if its remains (like a crash reason). Use this with care. |
|
387 | Forcibly deletes all locks if its remains (like a crash reason). Use this with care. | |
378 |
|
388 | |||
379 | :param redis_client: |
|
389 | :param redis_client: | |
380 | An instance of :class:`~StrictRedis`. |
|
390 | An instance of :class:`~StrictRedis`. | |
381 | """ |
|
391 | """ | |
382 | Lock.register_scripts(redis_client) |
|
392 | Lock.register_scripts(redis_client) | |
383 |
|
393 | |||
384 | reset_all_script(client=redis_client) # noqa |
|
394 | reset_all_script(client=redis_client) # noqa |
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