kestra-io/kestra · critical · PebbleException

The 'isLastWorkingDay()' function expects a 'date' argument.

Error message

The 'isLastWorkingDay()' function expects a 'date' argument.

What it means

The isLastWorkingDay() function requires a 'date' argument. This fires when date is null or missing.

Source

Thrown at core/src/main/java/io/kestra/core/runners/pebble/functions/IsLastWorkingDayFunction.java:49

 * </ul>
 *
 * @param date any valid ISO 8601 date or datetime string
 * @param workingDays optional comma- or space-separated list of day names (e.g. {@code "MONDAY,TUESDAY,WEDNESDAY,THURSDAY,FRIDAY"})
 */
public class IsLastWorkingDayFunction implements KestraFunction {
    public static final String NAME = "isLastWorkingDay";

    private static final Set<DayOfWeek> DEFAULT_WORKING_DAYS = EnumSet.of(
        DayOfWeek.MONDAY, DayOfWeek.TUESDAY, DayOfWeek.WEDNESDAY,
        DayOfWeek.THURSDAY, DayOfWeek.FRIDAY
    );

    @Override
    public Object execute(Map<String, Object> args, PebbleTemplate self, EvaluationContext context, int lineNumber) {
        Object dateArg = args.get("date");

        if (dateArg == null) {
            throw new PebbleException(null, "The 'isLastWorkingDay()' function expects a 'date' argument.", lineNumber, self.getName());
        }

        LocalDate localDate;
        try {
            localDate = DateUtils.parseLocalDate(dateArg.toString());
        } catch (InternalException e) {
            throw new PebbleException(e, "The 'isLastWorkingDay()' function could not parse 'date': " + e.getMessage(), lineNumber, self.getName());
        }

        Set<DayOfWeek> workingDays = resolveWorkingDays(args.get("workingDays"), self, lineNumber);

        if (!workingDays.contains(localDate.getDayOfWeek())) {
            return false;
        }

        // Walk backwards from the last calendar day of the month to find the last working day
        LocalDate lastOfMonth = localDate.with(TemporalAdjusters.lastDayOfMonth());
        LocalDate candidate = lastOfMonth;

View on GitHub (pinned to 823fada927)

Solutions

1. Pass a valid ISO date string as date (e.g. isLastWorkingDay(date='2024-01-31')).
2. Guard templated date values with 'is not empty' before calling.

Example fix

// before
{{ isLastWorkingDay() }}
// after
{{ isLastWorkingDay(date='2024-01-31') }}

{% if myDate is not empty %}{{ isLastWorkingDay(date=myDate) }}{% endif %}

When it happens

Trigger: Calling isLastWorkingDay() with no arguments, or with a date variable that resolved to null.

Common situations: Referencing an output that is not set, or forgetting the date argument.

Related errors

• The 'isDayWeekInMonth()' function expects a 'date' argument.
• The 'isDayWeekInMonth()' function expects a 'dayOfWeek' argu
• The 'isDayWeekInMonth()' function expects a 'position' argum
• The 'isPublicHoliday()' function expects a 'date' argument.
• The 'dayOfMonth()' function expects a 'date' argument.

AI-assisted analysis of kestra-io/kestra@823fada927 (2026-08-14). Data as JSON: /api/errors/8f630ace0fc05af0. Report an issue: GitHub.