Scheduled Events

1 Introduction

With scheduled events you can let the runtime execute a microflow at specific moments in time.

A scheduled event is added to your module as a document (right-click your module and you will find it listed under Add other).

2 Variants

Until Mendix 9.12.0 scheduled events only execute on the cluster leader node, with an at-most-once guarantee, which means that they will not be executed if something happens to the cluster leader node. Also, these scheduled events do not support proper monthly and yearly events and potentially suffer from a shift of one hour due to daylight saving. These ’legacy’ scheduled events are deprecated and will no longer be supported from Mendix 10.

As of Mendix 9.12.0 scheduled events have been improved and are being executed using the task queue, providing an at-least-once guarantee. They will be executed by an arbitrary node in the cluster and support monthly and yearly events properly.

Most importantly, you can no longer specify a specific date and time for task queue-based scheduled events — all events will recur at the specified time, depending on the schedule you set up.

In addition, these recurring events will now work as expected in the face of daylight saving time.

Mendix 9.12 and above supports the following schedule types:

• Legacy – the type that existing before Mendix 9.12.0 — see Legacy scheduled events
• Yearly – an event that occurs once a year on a specific day or date and at a specified time — see Yearly scheduled events
• Monthly – an event that occurs every so many months on a specific day and at a specified time — see Monthly scheduled events
• Weekly – an event that occurs weekly on specific days and at a specified time — see Weekly scheduled events
• Daily – an event that occurs daily at a specified time — see Daily scheduled events
• Hourly – an event that occurs every so many hours — see Hourly scheduled events
• Minutes – an event that occurs every so many minutes — see Minute scheduled events

3 Migration

When migrating to version 9.12.0 or above, Studio Pro will attempt to convert legacy scheduled events into task queue-based events, when possible. In cases where this is not possible, a deprecation warning will be shown (in versions 9.12.1 and above). Right-click the warning to see possible options for fixing it. If none of the options is suitable, you should perform the conversion manually.

The following cases cannot be converted automatically when the model is upgraded to Mendix 9.12.0 or above:

• The event is not repeating — remove the scheduled event or use the Java API to schedule a one-time action — we no-longer support non-repeating scheduled events.

• The event has a start-time in the future, which we’ll stop supporting — change the start-time to a date in the past or switch to a task queue based scheduled event.

• The event has interval type Month or Year, which is translated to 31 and 365 days respectively — use the Monthly or Yearly type instead.

• The event has interval type Seconds — use a schedule event with a 1-minute interval instead — we no-longer support scheduled events which repeat in less than a minute.

• The event has an interval that does not divide precisely into its next biggest interval type, for example an event that executes every 7 minutes; this will execute 8 times per hour, with 4 minutes left, causing it to ‘drift’ 4 minutes every hour.

  If it is absolutely critical that a non-supported interval is used, you should schedule the event with interval value of 1 (every minute) and then start your microflow with a decision that checks whether it should continue executing at that particular time.