date

This defines a date dependency for a node. There can be multiple date dependencies. The European format is used for dates, which is: dd.mm.yyyy as in 31.12.2012. Any of the three numeric fields can be expressed with a wildcard * to mean any valid value. For example, 01.*.* can be used to represent the first day of every month of every year.

Warning

A suite holding a node with a date attribute may never reach status complete.

A node with a date attribute is immediately set to queued after completion. In practice, this means that nodes containing a date attribute, and enveloping suites, only reach status complete when all specified date values have been exhausted – which might be never.

Extreme care is advised when creating completion triggers on nodes/suites containing date attributes.

Consider combining the date attribute together with event and complete attributes to avoid the suite never completing – see more about this usage pattern here.

Currently, a range of values cannot be used to specify any of the three numeric fields in a date. See day for a way to specify the first seven days.

task x          # Run the task twice a month
   date 1.*.*   # month, on 1st and 15th
   date 15.*.*

Because ecFlow was designed with ECMWF suites in mind, the date is a very important notion. ecFlow defines the time using clocks. A clock is an attribute of a suite. Different suites can have different clocks. There are two kinds of clocks:

  • Real clocks: A suite using a real clock will have its clock matching the clock of the machine.

  • Hybrid clocks: A hybrid clock is a complex notion: the date and time are not connected. The date has a fixed value during the complete execution of the suite. This will be mainly used in cases where the suite does not complete in less than 24 hours. This guarantees that all the tasks of this suite are using the same date. On the other hand, the time follows the time of the machine.

The value of the date is contained in the ecFlow variable ECF_DATE, and the value of the time is in variable ECF_TIME. The variable ECF_CLOCK contains other information such as the day of week. A well designed job should always use these ecFlow variables, and never directly access the system date.

If a hybrid clock is defined for a suite, any node held by a date dependency will be set to complete at the beginning of the suite, without the node ever being despatched. Otherwise the suite would never complete.