Remove UNIX_EPOCH and use the one in the core library

Also add the missing docs cross-reference for the core library.

Signed-off-by: Leandro Lucarella <[email protected]>

Author: llucax

RELEASE_NOTES.md

@@ -8,6 +8,7 @@
 
 * The microgrid client dependency has been updated to version 0.9.0
 * The resampling function now takes plain `float`s as values instead of `Quantity` objects.
+* `frequenz.sdk.timeseries.UNIX_EPOCH` was removed, use [`frequenz.core.datetime.UNIX_EPOCH`](https://frequenz-floss.github.io/frequenz-core-python/latest/reference/frequenz/core/datetime/#frequenz.core.datetime.UNIX_EPOCH) instead.
 
 ## New Features
 

mkdocs.yml

@@ -119,6 +119,7 @@ plugins:
             - https://docs.python.org/3/objects.inv
             - https://frequenz-floss.github.io/frequenz-channels-python/v1.1/objects.inv
             - https://frequenz-floss.github.io/frequenz-client-microgrid-python/v0.7/objects.inv
+            - https://frequenz-floss.github.io/frequenz-core-python/v1/objects.inv
             - https://frequenz-floss.github.io/frequenz-quantities-python/v1/objects.inv
             - https://lovasoa.github.io/marshmallow_dataclass/html/objects.inv
             - https://marshmallow.readthedocs.io/en/stable/objects.inv

src/frequenz/sdk/timeseries/__init__.py

@@ -9,8 +9,8 @@
 
 # Periodicity and alignment
 
-All the data produced by this package is always periodic and aligned to the
-`UNIX_EPOCH` (by default).
+All the data produced by this package is always periodic, in UTC, and aligned to the
+[Epoch](https://en.wikipedia.org/wiki/Epoch_(computing)) (by default).
 
 Classes normally take a (re)sampling period as and argument and, optionally, an
 `align_to` argument.
@@ -36,7 +36,7 @@
 """
 
 from .._internal._channels import ReceiverFetcher
-from ._base_types import UNIX_EPOCH, Bounds, Sample, Sample3Phase
+from ._base_types import Bounds, Sample, Sample3Phase
 from ._fuse import Fuse
 from ._moving_window import MovingWindow
 from ._periodic_feature_extractor import PeriodicFeatureExtractor
@@ -54,5 +54,4 @@
     "Sample",
     "Sample3Phase",
     "SourceProperties",
-    "UNIX_EPOCH",
 ]

src/frequenz/sdk/timeseries/_base_types.py

@@ -7,14 +7,11 @@
 import functools
 from collections.abc import Callable, Iterator
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import datetime
 from typing import Any, Generic, Protocol, Self, TypeVar, cast, overload
 
 from frequenz.quantities import Power, Quantity
 
-UNIX_EPOCH = datetime.fromtimestamp(0.0, tz=timezone.utc)
-"""The UNIX epoch (in UTC)."""
-
 QuantityT = TypeVar("QuantityT", bound=Quantity)
 """Type variable for representing various quantity types."""
 

src/frequenz/sdk/timeseries/_moving_window.py

@@ -13,11 +13,12 @@
 
 import numpy as np
 from frequenz.channels import Broadcast, Receiver, Sender
+from frequenz.core.datetime import UNIX_EPOCH
 from frequenz.quantities import Quantity
 from numpy.typing import ArrayLike
 
 from ..actor._background_service import BackgroundService
-from ._base_types import UNIX_EPOCH, Sample
+from ._base_types import Sample
 from ._resampling._config import ResamplerConfig
 from ._resampling._resampler import Resampler
 from ._ringbuffer import OrderedRingBuffer

src/frequenz/sdk/timeseries/_resampling/_config.py

@@ -12,7 +12,8 @@
 from datetime import datetime, timedelta
 from typing import Protocol
 
-from .._base_types import UNIX_EPOCH
+from frequenz.core.datetime import UNIX_EPOCH
+
 from ._base_types import SourceProperties
 
 _logger = logging.getLogger(__name__)

src/frequenz/sdk/timeseries/_ringbuffer/buffer.py

@@ -11,8 +11,9 @@
 
 import numpy as np
 import numpy.typing as npt
+from frequenz.core.datetime import UNIX_EPOCH
 
-from .._base_types import UNIX_EPOCH, QuantityT, Sample
+from .._base_types import QuantityT, Sample
 
 FloatArray = TypeVar("FloatArray", list[float], npt.NDArray[np.float64])
 """Type variable of the buffer container."""

tests/timeseries/test_moving_window.py

@@ -13,10 +13,10 @@
 import pytest
 import time_machine
 from frequenz.channels import Broadcast, Sender
+from frequenz.core.datetime import UNIX_EPOCH
 from frequenz.quantities import Quantity
 
 from frequenz.sdk.timeseries import (
-    UNIX_EPOCH,
     MovingWindow,
     ResamplerConfig,
     Sample,

tests/timeseries/test_periodic_feature_extractor.py

@@ -10,10 +10,10 @@
 import numpy as np
 import pytest
 from frequenz.channels import Broadcast
+from frequenz.core.datetime import UNIX_EPOCH
 from frequenz.quantities import Quantity
 
 from frequenz.sdk.timeseries import (
-    UNIX_EPOCH,
     MovingWindow,
     PeriodicFeatureExtractor,
     Sample,