visitorId property
A unique identifier for tracking visitors.
For example, this could be implemented with an HTTP cookie, which should be able to uniquely identify a visitor on a single device. This unique identifier should not change if the visitor logs in or out of the website. This should be the same identifier as UserEvent.visitor_id. The field must be a UTF-8 encoded string with a length limit of 128 characters. Otherwise, an INVALID_ARGUMENT error is returned.
Required.
Implementation
core.String? visitorId;