persistence
The persistence directory used by Ditto to persist data.
It is not recommended to directly read from or write to this directory, as its structure and contents are managed by Ditto and may change in future versions.
When DittoLogger is enabled, logs may be written to this directory even after a Ditto instance has been deallocated. Please refer to the documentation of DittoLogger for more information.
If null, a default persistence directory will be used, typically suffixed with the databaseId.