would it possible to support drop a slot on connection close for Postgresql connector?

[TDtianzhenjiu]

the debezium supports this property slot.drop.on.stop to support the drop slot after the app has been killed.
but it actually depends on the approach of how to kill the app. and most of the time it does not work.

since Postgresql supports creating temporary slots, once the session has been closed it will drop the slot automatically.
on the debezium side, however, it always returns false to indicate to create persist slot.
here is the code snippet

https://github.com/debezium/debezium/blob/DBZ-3414-fix-link-formatting-in-downstream-auto-topic-creation-doc/debezium-connector-postgres/src/main/java/io/debezium/connector/postgresql/connection/PostgresReplicationConnection.java#L261

// Temporary replication slots is a new feature of PostgreSQL 10
    private boolean useTemporarySlot() throws SQLException {
        // Temporary replication slots cannot be used due to connection restart
        // when finding WAL position
        // return dropSlotOnClose && pgConnection().haveMinimumServerVersion(ServerVersion.v10);
        return false;
    }

the official answer to this reason is that temporary replication slots cannot be used due to connection restart.

in the flink job, however, if the connection restarts we can throw an exception to let the job restart
although the slot has been dropped, after restarting, the flink CDC job can redo the snapshot, right?

So, IMO, in the fink CDC job, it is safe to create a temporary slot, am I right?