ecflow.Trigger

class ecflow.Trigger

Bases: instance

Add a trigger or complete expression.

This defines a dependency for a node. There can only be one trigger or complete expression dependency per node. A node with a trigger can only be activated when the trigger has expired. Triggers can reference nodes, events, meters, variables, repeats, limits and late flag A trigger holds a node as long as the expression returns false.

Exception:

  • Will throw RuntimeError if first expression is added as ‘AND’ or ‘OR’ expression Like wise second and subsequent expression must have ‘AND’ or ‘OR’ booleans set

Usage:

Multiple trigger will automatically be anded together, If or is required please use bool ‘False’ as the last argument i.e. :

task1.add( Trigger('t2 == active' ),
           Trigger('t1 == complete or t4 == complete' ),
           Trigger('t5 == active',False))

The trigger for task1 is equivalent to :

t2 == active and t1 == complete or t4 == complete or t5 == active

Since a large number of triggers are of the form <node> == complete there are are short cuts, these involves a use of a list :

task1.add( Trigger( ['t2','t3'] )) #  This is same as t2 == complete and t3 == complete

You can also use a node :

task1.add( Trigger( ['t2',taskx] ))

If the node ‘taskx’ has a parent, we use the full hierarchy, hence we will get a trigger of the form :

t2 ==complete and /suite/family/taskx == complete

If however node taskx has not yet been added to its parent, we use a relative name in the trigger :

t2 ==complete and taskx == complete
Trigger.get_expression((Trigger)arg1) → str :

returns the trigger expression as a string