Add datetime helpers to unify code

freqtrade/util/__init__.py

@@ -1,2 +1,11 @@
-from freqtrade.util.ft_precise import FtPrecise  # noqa: F401
+from freqtrade.util.datetime_helpers import dt_from_ts, dt_now
-from freqtrade.util.periodic_cache import PeriodicCache  # noqa: F401
+from freqtrade.util.ft_precise import FtPrecise
+from freqtrade.util.periodic_cache import PeriodicCache
+
+
+__all__ = [
+    'dt_from_ts',
+    'dt_now',
+    'FtPrecise',
+    'PeriodicCache',
+]

freqtrade/util/datetime_helpers.py

@@ -0,0 +1,17 @@
+from datetime import datetime, timezone
+
+
+def dt_now() -> datetime:
+    """Return the current datetime in UTC."""
+    return datetime.now(timezone.utc)
+
+
+def dt_from_ts(timestamp: float) -> datetime:
+    """
+    Return a datetime from a timestamp.
+    :param timestamp: timestamp in seconds or milliseconds
+    """
+    if timestamp > 1e10:
+        # Timezone in ms - convert to seconds
+        timestamp /= 1000
+    return datetime.fromtimestamp(timestamp, tz=timezone.utc)

tests/utils/test_datetime_helpers.py

@@ -0,0 +1,29 @@
+from datetime import datetime, timedelta, timezone
+
+import pytest
+import time_machine
+
+from freqtrade.util import dt_from_ts, dt_now
+
+
+def test_dt_now():
+    with time_machine.travel("2021-09-01 05:01:00 +00:00", tick=False) as t:
+        now = datetime.now(timezone.utc)
+        assert dt_now() == now
+
+        t.shift(timedelta(hours=5))
+        assert dt_now() >= now
+        assert dt_now() == datetime.now(timezone.utc)
+
+
+@pytest.mark.parametrize('as_ms', [True, False])
+def test_dt_from_ts(as_ms):
+    multi = 1000 if as_ms else 1
+    assert dt_from_ts(1683244800.0 * multi) == datetime(2023, 5, 5, tzinfo=timezone.utc)
+    assert dt_from_ts(1683244800.5555 * multi) == datetime(2023, 5, 5, 0, 0, 0, 555500,
+                                                           tzinfo=timezone.utc)
+    # As int
+    assert dt_from_ts(1683244800 * multi) == datetime(2023, 5, 5, tzinfo=timezone.utc)
+    # As milliseconds
+    assert dt_from_ts(1683244800 * multi) == datetime(2023, 5, 5, tzinfo=timezone.utc)
+    assert dt_from_ts(1683242400 * multi) == datetime(2023, 5, 4, 23, 20, tzinfo=timezone.utc)