Canton comes with the data source class for PostgresDB dataSourceClass = "org.postgresql.ds.PGSimpleDataSource"and it works well with PostgresDB. A client plans to use PostgresDB on Spanner, which requires some tuning on the class, and a JAR is ready.
May I know if it is possible to use a customised data source class in Canton? If yes, how to do so?
For this to work you need to have the corresponding JAR loaded.
Note that any custom data source that would be imported in such a way would not have been tested and is officially unsupported (use at your own risk).
Now, the Postgresql section of the spanner document indicates that only a subset of the sql syntax is supported. My guess is that the current set of supported queries will not be sufficient to run Canton.