James
50 lines
1.3 KiB
Python
50 lines
1.3 KiB
Python
from dataclasses import dataclass
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from datetime import datetime
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from typing import Callable, Generic, Optional, TypeVar
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from reactivex import Observable, abc, defer, operators
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from reactivex.scheduler import TimeoutScheduler
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_T = TypeVar("_T")
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@dataclass
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class Timestamp(Generic[_T]):
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value: _T
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timestamp: datetime
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def timestamp_(
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scheduler: Optional[abc.SchedulerBase] = None,
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) -> Callable[[Observable[_T]], Observable[Timestamp[_T]]]:
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def timestamp(source: Observable[_T]) -> Observable[Timestamp[_T]]:
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"""Records the timestamp for each value in an observable sequence.
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Examples:
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>>> timestamp(source)
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Produces objects with attributes `value` and `timestamp`, where
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value is the original value.
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Args:
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source: Observable source to timestamp.
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Returns:
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An observable sequence with timestamp information on values.
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"""
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def factory(scheduler_: Optional[abc.SchedulerBase] = None):
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_scheduler = scheduler or scheduler_ or TimeoutScheduler.singleton()
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def mapper(value: _T) -> Timestamp[_T]:
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return Timestamp(value=value, timestamp=_scheduler.now)
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return source.pipe(operators.map(mapper))
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return defer(factory)
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return timestamp
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__all__ = ["timestamp_"]
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