35 lines
1.2 KiB
Python
35 lines
1.2 KiB
Python
"""Time helpers: the DB holds naive UTC, presentation converts to display_timezone (#42)."""
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from datetime import datetime, timezone
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from zoneinfo import ZoneInfo
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from src.backend.config import settings
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def utcnow() -> datetime:
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"""Naive UTC now (the whole DB moves to naive UTC, #42)."""
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return datetime.now(timezone.utc).replace(tzinfo=None)
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def as_utc_naive(dt: datetime | None) -> datetime | None:
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"""Aware -> UTC naive; naive is taken as UTC already; None stays None."""
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if dt is None or dt.tzinfo is None:
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return dt
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return dt.astimezone(timezone.utc).replace(tzinfo=None)
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def to_utc_aware(dt: datetime) -> datetime:
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"""Naive (UTC) or aware datetime -> aware UTC."""
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if dt.tzinfo is None:
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return dt.replace(tzinfo=timezone.utc)
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return dt.astimezone(timezone.utc)
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def iso_utc(dt: datetime | None) -> str:
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"""ISO 8601 with explicit +00:00; "" for None (CSV cells)."""
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return to_utc_aware(dt).isoformat() if dt else ""
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def to_local(dt: datetime) -> datetime:
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"""Naive UTC (or aware) datetime -> aware datetime in settings.display_timezone."""
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return to_utc_aware(dt).astimezone(ZoneInfo(settings.display_timezone))
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