snapshot of https://github.com/zulip/zulip.git @ 48c69911c7dd4e03b20552eb3bd77ad8151c1357 (2026-09-15)

analytics/lib/time_utils.py

@@ -0,0 +1,33 @@
+from datetime import datetime, timedelta
+
+from analytics.lib.counts import CountStat
+from zerver.lib.timestamp import floor_to_day, floor_to_hour, verify_UTC
+
+
+# If min_length is None, returns end_times from ceiling(start) to floor(end), inclusive.
+# If min_length is greater than 0, pads the list to the left.
+# So informally, time_range(Sep 20, Sep 22, day, None) returns [Sep 20, Sep 21, Sep 22],
+# and time_range(Sep 20, Sep 22, day, 5) returns [Sep 18, Sep 19, Sep 20, Sep 21, Sep 22]
+def time_range(
+    start: datetime, end: datetime, frequency: str, min_length: int | None
+) -> list[datetime]:
+    verify_UTC(start)
+    verify_UTC(end)
+    if frequency == CountStat.HOUR:
+        end = floor_to_hour(end)
+        step = timedelta(hours=1)
+    elif frequency == CountStat.DAY:
+        end = floor_to_day(end)
+        step = timedelta(days=1)
+    else:
+        raise AssertionError(f"Unknown frequency: {frequency}")
+
+    times = []
+    if min_length is not None:
+        start = min(start, end - (min_length - 1) * step)
+    current = end
+    while current >= start:
+        times.append(current)
+        current -= step
+    times.reverse()
+    return times