Beispiel #1
0
    def __get_timestamp(self, msg):
        """Get a timestamp, non-recursively"""
        serialized_timestamp = self.db.Get(msg)
        ctx = BytesDeserializationContext(serialized_timestamp)

        timestamp = Timestamp(msg)

        for i in range(ctx.read_varuint()):
            attestation = TimeAttestation.deserialize(ctx)
            assert attestation not in timestamp.attestations
            timestamp.attestations.add(attestation)

        for i in range(ctx.read_varuint()):
            op = Op.deserialize(ctx)
            assert op not in timestamp.ops
            timestamp.ops.add(op)

        return timestamp
    def __get_timestamp(self, msg):
        """Get a timestamp, non-recursively"""
        serialized_timestamp = self.db.Get(msg)
        ctx = BytesDeserializationContext(serialized_timestamp)

        timestamp = Timestamp(msg)

        for i in range(ctx.read_varuint()):
            attestation = TimeAttestation.deserialize(ctx)
            assert attestation not in timestamp.attestations
            timestamp.attestations.add(attestation)

        for i in range(ctx.read_varuint()):
            op = Op.deserialize(ctx)
            assert op not in timestamp.ops
            timestamp.ops.add(op)

        return timestamp
    def loop(self):
        logging.info("Starting loop for %s" % self.calendar_url)

        try:
            logging.debug("Opening %s" % self.up_to_path)
            with open(self.up_to_path, 'r') as up_to_fd:
                last_known = int(up_to_fd.read().strip())
        except FileNotFoundError as exp:
            last_known = -1
        logging.info("Checking calendar " + str(self.calendar_url) +
                     ", last_known commitment:" + str(last_known))

        if self.btc_net == 'testnet':
            bitcoin.SelectParams('testnet')
        elif self.btc_net == 'regtest':
            bitcoin.SelectParams('regtest')

        while True:
            start_time = time.time()
            backup_url = urljoin(self.calendar_url,
                                 "/experimental/backup/%d" % (last_known + 1))
            logging.debug("Asking " + str(backup_url))
            try:
                r = requests.get(backup_url)
            except Exception as err:
                logging.error(
                    "Exception asking %s error message %s, sleeping for %d seconds"
                    % (str(backup_url), str(err), SLEEP_SECS))
                time.sleep(SLEEP_SECS)
                continue

            if r.status_code != 200:
                logging.info("%s not found, sleeping for %d seconds" %
                             (backup_url, SLEEP_SECS))
                time.sleep(SLEEP_SECS)
                continue

            kv_map = Backup.bytes_to_kv_map(r.content)
            attestations = {}
            ops = {}
            for key, value in kv_map.items():
                # print("--- key=" + b2x(key) + " value=" + b2x(value))
                ctx = BytesDeserializationContext(value)

                for _a in range(ctx.read_varuint()):
                    attestation = TimeAttestation.deserialize(ctx)
                    attestations[key] = attestation

                for _b in range(ctx.read_varuint()):
                    op = Op.deserialize(ctx)
                    ops[key] = op

            proxy = bitcoin.rpc.Proxy()

            # Verify all bitcoin attestation are valid
            logging.debug("Total attestations: " + str(len(attestations)))
            for key, attestation in attestations.items():
                if attestation.__class__ == BitcoinBlockHeaderAttestation:
                    blockhash = proxy.getblockhash(attestation.height)
                    block_header = proxy.getblockheader(blockhash)
                    # the following raise an exception and block computation if the attestation does not verify
                    attested_time = attestation.verify_against_blockheader(
                        key, block_header)
                    logging.debug("Verifying " + b2x(key) + " result " +
                                  str(attested_time))

            # verify all ops connects to an attestation
            logging.debug("Total ops: " + str(len(ops)))
            for key, op in ops.items():
                current_key = key
                current_op = op
                while True:
                    next_key = current_op(current_key)
                    if next_key in ops:
                        current_key = next_key
                        current_op = ops[next_key]
                    else:
                        break
                assert next_key in attestations

            batch = leveldb.WriteBatch()
            for key, value in kv_map.items():
                batch.Put(key, value)
            self.db.db.Write(batch, sync=True)

            last_known = last_known + 1
            try:
                with open(self.up_to_path, 'w') as up_to_fd:
                    up_to_fd.write('%d\n' % last_known)
            except FileNotFoundError as exp:
                logging.error(str(exp))
                break

            elapsed_time = time.time() - start_time
            logging.info("Took %ds for %s" % (elapsed_time, str(backup_url)))