Filters

Most activities have a Filter expression that when set will direct the parent Flow to terminate under specific conditions.

An activity’s Filter becomes active immediately after the activity finishes execution but before branching to children occurs.

Once active a Filter will evaluate to either TRUE or FALSE.

When TRUE the parent Flow and activity will continue execution as normal. When FALSE the parent Flow will halt execution and immediately terminate.

Scoping of Output variables for the current activity includes the activity Id as filters are evaluated AFTER execution. So assuming you have an activity called myactivity and it returns and output called success a valid filter expression would be myactivity.success == true

Usage Tips

Filters are intended as a shorthand for situations where a Flow needs to be immediately terminated if a certain condition is met.

Common uses include:

• Further filtering incoming events from a Trigger beyond the point the basic logic of the Trigger supports
• Quickly terminating a Flow if a bad/invalid/undesirable state is detected

If the binary logic of a Filter is too simple for a given situation, consider using the Condition Primitive which allows for more complex conditional branching.