A Flow has to fulfill certain conditions in order to be considered valid. The validity rules exist mostly to prevent Flows with erroneous or nonsensical constructs to not be run. It is fairly difficult to not fulfill the rules with Online editor -constructed Flows, so these aren't generally much to worry about.
A Flow is considered invalid and cannot be run if any of the following are true:
- Flow contains no Segment.
- A Segment's event mapping has no ID.
- A Segment's event or default event mapping doesn't specify any Step.
- A Segment contains no Step.
- A step (of any of the three kinds) has no ID.
Forms have their own validity concerns. Should any of the following be true, the Flow will be forcibly interrupted when the Form is reached:
- The resources or data to be used in the Form cannot be found.
- The HTML source of the Form cannot be parsed as XML.
Limitations during operation
A Flow can be valid, but it may still be forcibly interrupted while it is running due to certain limitations being in place. Several of these limitations can be avoided through the Flow's design. The general Flow limitations are as follows:
- No more than 100 steps can be evaluated as a Flow is run. This is to prevent infinite step loops from occurring.
- No more than 20 Flow steps can be evaluated as a Flow is run. Any Flow steps evaluated within the Subflows are counted.
- A standard Step cannot last for over 3 minutes.
- A Form cannot display its screen for over 60 minutes.