fix(rule_func): time zone shift at wrong precision

apps/emqx_rule_engine/test/emqx_rule_funcs_SUITE.erl

@@ -1181,7 +1181,18 @@ t_parse_date_errors(_) ->
     ?assertEqual(
         UnixTsLeap2,
         emqx_rule_funcs:date_to_unix_ts(second, <<"%Y-%m-%d %H:%M:%S">>, <<"2024-03-04 06:56:27">>)
-    ).
+    ),
+
+    %% None zero zone shift with millisecond level precision
+    Tz1 = calendar:rfc3339_to_system_time("2024-02-23T15:00:00.123+08:00", [{unit, second}]),
+    ?assertEqual(
+        Tz1,
+        emqx_rule_funcs:date_to_unix_ts(
+            second, <<"%Y-%m-%d %H:%M:%S.%3N%:z">>, <<"2024-02-23 15:00:00.123+08:00">>
+        )
+    ),
+
+    ok.
 
 %%------------------------------------------------------------------------------
 %% Utility functions

apps/emqx_utils/src/emqx_utils_calendar.erl

@@ -507,7 +507,7 @@ do_parse(DateStr, Unit, Formatter) ->
             (nanosecond, V, Res) ->
                 Res + V;
             (parsed_offset, V, Res) ->
-                Res - V
+                Res - V * Precise
         end,
     Count = maps:fold(Counter, 0, DateInfo) - (?SECONDS_PER_DAY * Precise),
     erlang:convert_time_unit(Count, PrecisionUnit, Unit).

changes/ce/fix-12646.en.md

@@ -0,0 +1,3 @@
+Fix rule engine date time string parser.
+
+Prior to this fix, time zone shift can only work when date time string is at second level precision.