start project

app/utils/dates.py

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+"""Shared from/to date-range parsing (Chapter 11: consistent across every
+chart/KPI endpoint; never defaults to "all time" per Chapter 03 rule 7).
+"""
+from __future__ import annotations
+
+from datetime import date, datetime, timedelta
+
+from flask import Request
+
+DEFAULT_RANGE_DAYS = 7  # within Ch11's stated "7 or 30 day" default allowance
+
+
+def parse_date_range(request: Request) -> tuple[date, date]:
+    """Parse `?from=&to=` (ISO 8601 dates), defaulting to the last 7 days."""
+    to_raw = request.args.get("to")
+    from_raw = request.args.get("from")
+    to_date = date.fromisoformat(to_raw) if to_raw else date.today()
+    from_date = date.fromisoformat(from_raw) if from_raw else to_date - timedelta(days=DEFAULT_RANGE_DAYS - 1)
+    if from_date > to_date:
+        from_date, to_date = to_date, from_date
+    return from_date, to_date
+
+
+def day_bounds(from_date: date, to_date: date) -> tuple[datetime, datetime]:
+    """Inclusive [from_date, to_date] -> half-open [start, end) datetime range.
+
+    Shared by overview/queries.py, seo/queries.py, and security/queries.py
+    (consolidated here rather than each keeping its own local copy).
+    """
+    start = datetime.combine(from_date, datetime.min.time())
+    end = datetime.combine(to_date, datetime.min.time()) + timedelta(days=1)
+    return start, end