1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251
|
import logging
import threading
from datetime import datetime, timedelta
from typing import Any, Optional, TypeVar
from reactivex import abc, typing
from reactivex.abc.scheduler import AbsoluteTime
from reactivex.internal import ArgumentOutOfRangeException, PriorityQueue
from .periodicscheduler import PeriodicScheduler
from .scheduleditem import ScheduledItem
log = logging.getLogger("Rx")
MAX_SPINNING = 100
_TState = TypeVar("_TState")
class VirtualTimeScheduler(PeriodicScheduler):
"""Virtual Scheduler. This scheduler should work with either
datetime/timespan or ticks as int/int"""
def __init__(self, initial_clock: AbsoluteTime = 0) -> None:
"""Creates a new virtual time scheduler with the specified
initial clock value.
Args:
initial_clock: Initial value for the clock.
"""
super().__init__()
self._clock: AbsoluteTime = initial_clock
self._is_enabled = False
self._lock: threading.Lock = threading.Lock()
self._queue: PriorityQueue[ScheduledItem] = PriorityQueue()
def _get_clock(self) -> typing.AbsoluteTime:
with self._lock:
return self._clock
clock = property(fget=_get_clock)
@property
def now(self) -> datetime:
"""Represents a notion of time for this scheduler. Tasks being
scheduled on a scheduler will adhere to the time denoted by this
property.
Returns:
The scheduler's current time, as a datetime instance.
"""
return self.to_datetime(self._clock)
def schedule(
self, action: typing.ScheduledAction[_TState], state: Optional[_TState] = None
) -> abc.DisposableBase:
"""Schedules an action to be executed.
Args:
action: Action to be executed.
state: [Optional] state to be given to the action function.
Returns:
The disposable object used to cancel the scheduled action
(best effort).
"""
return self.schedule_absolute(self._clock, action, state=state)
def schedule_relative(
self,
duetime: typing.RelativeTime,
action: abc.ScheduledAction[_TState],
state: Optional[_TState] = None,
) -> abc.DisposableBase:
"""Schedules an action to be executed after duetime.
Args:
duetime: Relative time after which to execute the action.
action: Action to be executed.
state: [Optional] state to be given to the action function.
Returns:
The disposable object used to cancel the scheduled action
(best effort).
"""
time: typing.AbsoluteTime = self.add(self._clock, duetime)
return self.schedule_absolute(time, action, state=state)
def schedule_absolute(
self,
duetime: typing.AbsoluteTime,
action: abc.ScheduledAction[_TState],
state: Optional[_TState] = None,
) -> abc.DisposableBase:
"""Schedules an action to be executed at duetime.
Args:
duetime: Absolute time at which to execute the action.
action: Action to be executed.
state: [Optional] state to be given to the action function.
Returns:
The disposable object used to cancel the scheduled action
(best effort).
"""
dt = self.to_datetime(duetime)
si: ScheduledItem = ScheduledItem(self, state, action, dt)
with self._lock:
self._queue.enqueue(si)
return si.disposable
def start(self) -> Any:
"""Starts the virtual time scheduler."""
with self._lock:
if self._is_enabled:
return
self._is_enabled = True
spinning: int = 0
while True:
with self._lock:
if not self._is_enabled or not self._queue:
break
item: ScheduledItem = self._queue.dequeue()
if item.duetime > self.now:
if isinstance(self._clock, datetime):
self._clock = item.duetime
else:
self._clock = self.to_seconds(item.duetime)
spinning = 0
elif spinning > MAX_SPINNING:
if isinstance(self._clock, datetime):
self.clock += timedelta(microseconds=1000)
else:
self._clock += 1.0
spinning = 0
if not item.is_cancelled():
item.invoke()
spinning += 1
self.stop()
def stop(self) -> None:
"""Stops the virtual time scheduler."""
with self._lock:
self._is_enabled = False
def advance_to(self, time: typing.AbsoluteTime) -> None:
"""Advances the schedulers clock to the specified absolute time,
running all work til that point.
Args:
time: Absolute time to advance the schedulers clock to.
"""
item: ScheduledItem
dt: datetime = self.to_datetime(time)
with self._lock:
if self.now > dt:
raise ArgumentOutOfRangeException()
if self.now == dt or self._is_enabled:
return
self._is_enabled = True
while True:
with self._lock:
if not self._is_enabled or not self._queue:
break
item = self._queue.peek()
if item.duetime > dt:
break
if item.duetime > self.now:
if isinstance(self._clock, datetime):
self._clock = item.duetime
else:
self._clock = self.to_seconds(item.duetime)
self._queue.dequeue()
if not item.is_cancelled():
item.invoke()
with self._lock:
self._is_enabled = False
if isinstance(self._clock, datetime):
self._clock = dt
else:
self._clock = self.to_seconds(dt)
def advance_by(self, time: typing.RelativeTime) -> None:
"""Advances the schedulers clock by the specified relative time,
running all work scheduled for that timespan.
Args:
time: Relative time to advance the schedulers clock by.
"""
log.debug("VirtualTimeScheduler.advance_by(time=%s)", time)
self.advance_to(self.add(self.now, self.to_timedelta(time)))
def sleep(self, time: typing.RelativeTime) -> None:
"""Advances the schedulers clock by the specified relative time.
Args:
time: Relative time to advance the schedulers clock by.
"""
absolute = self.add(self.now, self.to_timedelta(time))
dt: datetime = self.to_datetime(absolute)
if self.now > dt:
raise ArgumentOutOfRangeException()
with self._lock:
if isinstance(self._clock, datetime):
self._clock = dt
else:
self._clock = self.to_seconds(dt)
@classmethod
def add(
cls, absolute: typing.AbsoluteTime, relative: typing.RelativeTime
) -> typing.AbsoluteTime:
"""Adds a relative time value to an absolute time value.
Args:
absolute: Absolute virtual time value.
relative: Relative virtual time value to add.
Returns:
The resulting absolute virtual time sum value.
"""
return cls.to_datetime(absolute) + cls.to_timedelta(relative)
|