This is usually an implementation of Ledger

def init_domain_ledger(self):
        """
        This is usually an implementation of Ledger
        """
        if self.config.primaryStorage is None:
            genesis_txn_initiator = GenesisTxnInitiatorFromFile(
                self.genesis_dir, self.config.domainTransactionsFile)
            return Ledger(
                CompactMerkleTree(
                    hashStore=self.getHashStore('domain')),
                dataDir=self.dataLocation,
                fileName=self.config.domainTransactionsFile,
                ensureDurability=self.config.EnsureLedgerDurability,
                genesis_txn_initiator=genesis_txn_initiator)
        else:
            return initStorage(self.config.primaryStorage,
                               name=self.name + NODE_PRIMARY_STORAGE_SUFFIX,
                               dataDir=self.dataLocation,
                               config=self.config)