| time | A string expression containing a unix-standard cron time. |
| Return: | CRON defines a single timer event. |
The CRON function defines a timer event for use within the WHEN workflow service or WAIT function. This is synonymous with EVENT('CRON', time).
The time parameter is unix-standard cron time, expressed in UTC (aka Greenwich Mean Time) as a string containing the following, space-delimited components:
minute hour dom month dow
| minute | An integer value for the minute of the hour. Valid values are from 0 to 59. |
| hour | An integer value for the hour. Valid values are from 0 to 23 (using the 24 hour clock). |
| dom | An integer value for the day of the month. Valid values are from 1 to 31. |
| month | An integer value for the month. Valid values are from 1 to 12. |
| dow | An integer value for the day of the week. Valid values are from 0 to 6 (where 0 represents Sunday). |
Any time component that you do not want to pass is replaced by an asterisk (*). You may define ranges of times using a dash (-), lists using a comma (,), and 'once every n' using a slash (/). For example, 6-18/3 in the hour field will fire the timer every three hours between 6am and 6pm, and 18-21/3,0-6/3 will fire the timer every three hours between 6pm and 6am.
Example:
EXPORT events := MODULE
EXPORT dailyAtMidnight := CRON('0 0 * * *');
EXPORT dailyAt( INTEGER hour,
INTEGER minute=0) :=
EVENT('CRON',
(STRING)minute + ' ' + (STRING)hour + ' * * *');
EXPORT dailyAtMidday := dailyAt(12, 0);
EXPORT EveryThreeHours := CRON('0 0-23/3 * * *');
END;
BUILD(teenagers) : WHEN(events.dailyAtMidnight);
BUILD(oldies) : WHEN(events.dailyAt(6));
BUILD(NewStuff) : WHEN(events.EveryThreeHours);