What’s new in version 1.4
A value transformer is a value reader that is used to transform a value after it has been read or before it has been written. They are used in cases where the value read or that will be written needs to be converted into another format before it can be used in a synchronization process.
This feature is used for things such as handling guid values in Sitecore. Usually when a field value is a guid it means the field value is a reference to a Sitecore item. But when data from an external system is stored in Sitecore item fields, it is possible that the guid represents an identifier in the external system instead.
During a synchronization process, it may be important for the value to be a guid. A value transformer can be used to ensure the string value stored in Sitecore is converted into a guid when the value is read from the Sitecore item within a synchronization process.
Additionally, a value transform can be used to ensure the guid is converted into a string before the value is written to a Sitecore item.
For more details, see Item Field Value.