fix(feature_flags): handle same-hour midnight rollover and reject malformed HH:MM

aws_lambda_powertools/utilities/feature_flags/comparators.py

@@ -55,10 +55,15 @@ def compare_time_range(context_value: Any, condition_value: dict) -> bool:
     start_time = current_time.replace(hour=int(start_hour), minute=int(start_min))
     end_time = current_time.replace(hour=int(end_hour), minute=int(end_min))
 
-    if int(end_hour) < int(start_hour):
+    # Compare full minutes-since-midnight so that ranges within the same hour (e.g. 23:30 -> 23:00)
+    # are correctly detected as crossing midnight.
+    start_minutes = int(start_hour) * 60 + int(start_min)
+    end_minutes = int(end_hour) * 60 + int(end_min)
+
+    if end_minutes < start_minutes:
         # In normal circumstances, we need to assert **both** conditions
         """
-        # When the end hour is smaller than start hour, it means we are crossing a day's boundary.
+        # When the end time is earlier than start time, it means we are crossing a day's boundary.
         # In this case we need to assert that current_time is **either** on one side or the other side of the boundary
         #
         # ┌─────┐                                    ┌─────┐                                  ┌─────┐

aws_lambda_powertools/utilities/feature_flags/constants.py

@@ -9,5 +9,5 @@
 CONDITION_ACTION = "action"
 FEATURE_DEFAULT_VAL_TYPE_KEY = "boolean_type"
 TIME_RANGE_FORMAT = "%H:%M"  # hour:min 24 hours clock
-TIME_RANGE_PATTERN = re.compile(r"2[0-3]:[0-5]\d|[0-1]\d:[0-5]\d")  # 24 hour clock
+TIME_RANGE_PATTERN = re.compile(r"^(?:2[0-3]|[01]\d):[0-5]\d$")  # 24 hour clock, exactly HH:MM
 HOUR_MIN_SEPARATOR = ":"

tests/functional/feature_flags/_boto3/test_schema_validation.py

@@ -523,6 +523,9 @@ def test_validate_time_condition_between_time_range_invalid_condition_value_inva
     [
         {TimeValues.START.value: "11-11", TimeValues.END.value: "23:59"},
         {TimeValues.START.value: "24:99", TimeValues.END.value: "23:59"},
+        {TimeValues.START.value: "10:00abc", TimeValues.END.value: "23:59"},  # trailing garbage
+        {TimeValues.START.value: "abc10:00", TimeValues.END.value: "23:59"},  # leading garbage
+        {TimeValues.START.value: "110:00", TimeValues.END.value: "23:59"},  # extra leading digit
     ],
 )
 def test_validate_time_condition_between_time_range_invalid_condition_value_invalid_start_time_value(cond_value):
@@ -549,6 +552,8 @@ def test_validate_time_condition_between_time_range_invalid_condition_value_inva
     [
         {TimeValues.START.value: "10:11", TimeValues.END.value: "11-11"},
         {TimeValues.START.value: "10:11", TimeValues.END.value: "999:59"},
+        {TimeValues.START.value: "10:11", TimeValues.END.value: "12:00abc"},  # trailing garbage
+        {TimeValues.START.value: "10:11", TimeValues.END.value: "12:000"},  # extra trailing digit
     ],
 )
 def test_validate_time_condition_between_time_range_invalid_condition_value_invalid_end_time_value(cond_value):

tests/functional/feature_flags/_boto3/test_time_based_actions.py

@@ -175,6 +175,50 @@ def test_time_based_utc_in_between_time_range_between_days_rule_no_match(mocker)
     )
 
 
+def test_time_based_utc_in_between_time_range_same_hour_between_days_rule_match(mocker):
+    # GIVEN a range whose END is earlier than START but within the same hour (23:30 -> 23:00)
+    # WHEN the current time is 10:00, which lies inside the range after crossing midnight
+    # THEN the rule matches
+    assert evaluate_mocked_schema(
+        mocker=mocker,
+        rules={
+            "lambda time is between UTC 23:30-23:00": {
+                RULE_MATCH_VALUE: True,
+                CONDITIONS_KEY: [
+                    {
+                        CONDITION_ACTION: RuleAction.SCHEDULE_BETWEEN_TIME_RANGE.value,
+                        CONDITION_KEY: TimeKeys.CURRENT_TIME.value,
+                        CONDITION_VALUE: {TimeValues.START.value: "23:30", TimeValues.END.value: "23:00"},
+                    },
+                ],
+            },
+        },
+        mocked_time=(2022, 2, 15, 10, 0, 0, datetime.timezone.utc),  # rule match 10:00 am
+    )
+
+
+def test_time_based_utc_in_between_time_range_same_hour_between_days_rule_no_match(mocker):
+    # GIVEN a range whose END is earlier than START but within the same hour (23:30 -> 23:00)
+    # WHEN the current time is 23:15, the only 30-minute gap not covered by the range
+    # THEN the rule does not match
+    assert not evaluate_mocked_schema(
+        mocker=mocker,
+        rules={
+            "lambda time is between UTC 23:30-23:00": {
+                RULE_MATCH_VALUE: True,
+                CONDITIONS_KEY: [
+                    {
+                        CONDITION_ACTION: RuleAction.SCHEDULE_BETWEEN_TIME_RANGE.value,
+                        CONDITION_KEY: TimeKeys.CURRENT_TIME.value,
+                        CONDITION_VALUE: {TimeValues.START.value: "23:30", TimeValues.END.value: "23:00"},
+                    },
+                ],
+            },
+        },
+        mocked_time=(2022, 2, 15, 23, 15, 0, datetime.timezone.utc),  # rule no match 23:15
+    )
+
+
 def test_time_based_between_time_range_rule_timezone_match(mocker):
     timezone_name = "Europe/Copenhagen"