Issue with configuring Schedules with Java SDK

Community Support
1

I’m developing functionality where I need to send reminders to users after every 12 hours. I want to configure a schedule such that it’ll initiate a workflow 12 hours after schedule creation time.

First approach -
In the first approach I initiated schedule with setStartDelay of 12 hours. In this case first workflow run was scheduled at 12:00 UTC instead of 12 hours after the schedule creation time.

Schedule schedule = Schedule.newBuilder()
.setAction(
    ScheduleActionStartWorkflow.newBuilder()
        .setWorkflowType(ReminderWorkflow.class)
        .setArguments(workflowInput)
        .setOptions(
            WorkflowOptions.newBuilder()
                .setStartDelay(Duration.ofHours(12))
                .setWorkflowId(referenceId)
                .setTaskQueue(taskQueue)
                .build())
        .build())
.setSpec(ScheduleSpec.newBuilder()
    .setIntervals(Collections.singletonList(new ScheduleIntervalSpec(Duration.ofHours(12))))
    .setTimeZoneName("Asia/Kolkata")
    .build())
.build();

Schedule details

Schedule Created: 2024-09-12 UTC 10:28:32.28

Upcoming Runs as observed from temporal UI
2024-09-12 UTC 12:00:00.00

2024-09-13 UTC 00:00:00.00

2024-09-13 UTC 12:00:00.00

2024-09-14 UTC 00:00:00.00

2024-09-14 UTC 12:00:00.00

Second approach -
In second approach I removed the setStartDelay and used setCalendars. In this case also the first workflow run was scheduled at 12:00 UTC instead of 12 hours after the schedule creation time. Additionally, second workflow run was scheduled after the 12 hours.

LocalDateTime scheduleStartTime = LocalDateTime.now().plusHours(12);
Schedule schedule = Schedule.newBuilder()
.setAction(
    ScheduleActionStartWorkflow.newBuilder()
        .setWorkflowType(ReminderWorkflow.class)
        .setArguments(workflowInput)
        .setOptions(
            WorkflowOptions.newBuilder()
                .setWorkflowId(referenceId)
                .setTaskQueue(taskQueue)
                .build())
        .build())
.setSpec(ScheduleSpec.newBuilder()
    .setCalendars(
        Collections.singletonList(
            ScheduleCalendarSpec.newBuilder()
                .setDayOfMonth(Collections.singletonList(new ScheduleRange(scheduleStartTime.getDayOfMonth())))
                .setHour(Collections.singletonList(new ScheduleRange(scheduleStartTime.getHour())))
                .setMinutes(Collections.singletonList(new ScheduleRange(scheduleStartTime.getMinute())))
                .setSeconds(Collections.singletonList(new ScheduleRange(scheduleStartTime.getSecond())))
                .build()))
    .setIntervals(Collections.singletonList(new ScheduleIntervalSpec(Duration.ofHours(12))))
    .setTimeZoneName("Asia/Kolkata")
    .build())
.build();

Schedule details

Schedule Created: 2024-09-12 UTC 10:26:28.07

Upcoming Runs as observed from temporal UI
2024-09-12 UTC 12:00:00.00

2024-09-12 UTC 22:26:28.00

2024-09-13 UTC 00:00:00.00

2024-09-13 UTC 12:00:00.00

2024-09-14 UTC 00:00:00.00

Also setTimeZoneName doesn’t seem to have an impact on the outcome.
Is there something wrong with the way schedule is configured?