Source code for bitcoinlib.db_cache

# -*- coding: utf-8 -*-
#
#    BitcoinLib - Python Cryptocurrency Library
#    Cache DataBase - SqlAlchemy database definitions for caching
#    © 2020 February - 1200 Web Development <http://1200wd.com/>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as
#    published by the Free Software Foundation, either version 3 of the
#    License, or (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU Affero General Public License for more details.
#
#    You should have received a copy of the GNU Affero General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

from sqlalchemy import create_engine
from sqlalchemy import Column, Integer, BigInteger, String, Boolean, ForeignKey, DateTime, Enum, LargeBinary
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, relationship, close_all_sessions
# try:
#     import mysql.connector
#     from parameterized import parameterized_class
#     import psycopg2
#     from psycopg2 import sql
#     from psycopg2.extensions import ISOLATION_LEVEL_AUTOCOMMIT
# except ImportError as e:
#     print("Could not import all modules. Error: %s" % e)
#     # from psycopg2cffi import compat  # Use for PyPy support
#     # compat.register()
#     pass  # Only necessary when mysql or postgres is used
from urllib.parse import urlparse
from bitcoinlib.main import *


_logger = logging.getLogger(__name__)
try:
    dbcacheurl_obj = urlparse(DEFAULT_DATABASE_CACHE)
    if dbcacheurl_obj.netloc:
        dbcacheurl = dbcacheurl_obj.netloc.replace(dbcacheurl_obj.password, 'xxx')
    else:
        dbcacheurl = dbcacheurl_obj.path
    _logger.info("Default Cache Database %s" % dbcacheurl)
except Exception:
    _logger.warning("Default Cache Database: unable to parse URL")
Base = declarative_base()


[docs]class WitnessTypeTransactions(enum.Enum): legacy = "legacy" segwit = "segwit"
[docs]class DbCache: """ Cache Database object. Initialize database and open session when creating database object. Create new database if is doesn't exist yet """ def __init__(self, db_uri=None): self.engine = None self.session = None if db_uri is None: db_uri = DEFAULT_DATABASE_CACHE elif not db_uri: return self.o = urlparse(db_uri) # if self.o.scheme == 'mysql': # raise Warning("Could not connect to cache database. MySQL databases not supported at the moment, " # "because bytes strings are not supported as primary keys") if not self.o.scheme or len(self.o.scheme) < 2: db_uri = 'sqlite:///%s' % db_uri if db_uri.startswith("sqlite://") and ALLOW_DATABASE_THREADS: db_uri += "&" if "?" in db_uri else "?" db_uri += "check_same_thread=False" if self.o.scheme == 'mysql': db_uri += "&" if "?" in db_uri else "?" db_uri += 'binary_prefix=true' self.engine = create_engine(db_uri, isolation_level='READ UNCOMMITTED') Session = sessionmaker(bind=self.engine) Base.metadata.create_all(self.engine) self.db_uri = db_uri _logger.info("Using cache database: %s://%s:%s/%s" % (self.o.scheme or '', self.o.hostname or '', self.o.port or '', self.o.path or '')) self.session = Session()
[docs] def drop_db(self): self.session.commit() self.session.close_all() close_all_sessions() Base.metadata.drop_all(self.engine)
[docs]class DbCacheTransactionNode(Base): """ Link table for cache transactions and addresses """ __tablename__ = 'cache_transactions_node' txid = Column(LargeBinary(32), ForeignKey('cache_transactions.txid'), primary_key=True) transaction = relationship("DbCacheTransaction", back_populates='nodes', doc="Related transaction object") index_n = Column(Integer, primary_key=True, doc="Order of input/output in this transaction") value = Column(BigInteger, default=0, doc="Value of transaction input") address = Column(String(255), index=True, doc="Address string base32 or base58 encoded") script = Column(LargeBinary, doc="Locking or unlocking script") witnesses = Column(LargeBinary, doc="Witnesses (signatures) used in Segwit transaction inputs") sequence = Column(BigInteger, default=0xffffffff, doc="Transaction sequence number. Used for timelock transaction inputs") is_input = Column(Boolean, primary_key=True, doc="True if input, False if output") spent = Column(Boolean, default=None, doc="Is output spent?") ref_txid = Column(LargeBinary(32), index=True, doc="Transaction hash of input which spends this output") ref_index_n = Column(BigInteger, doc="Index number of transaction input which spends this output")
[docs] def prev_txid(self): if self.is_input: return self.ref_txid
[docs] def output_n(self): if self.is_input: return self.ref_index_n
[docs] def spending_txid(self): if not self.is_input: return self.ref_txid
[docs] def spending_index_n(self): if not self.is_input: return self.ref_index_n
[docs]class DbCacheTransaction(Base): """ Transaction Cache Table Database which stores transactions received from service providers as cache """ __tablename__ = 'cache_transactions' txid = Column(LargeBinary(32), primary_key=True, doc="Hexadecimal representation of transaction hash or transaction ID") date = Column(DateTime, doc="Date when transaction was confirmed and included in a block") version = Column(BigInteger, default=1, doc="Tranaction version. Default is 1 but some wallets use another version number") locktime = Column(BigInteger, default=0, doc="Transaction level locktime. Locks the transaction until a specified block " "(value from 1 to 5 million) or until a certain time (Timestamp in seconds after 1-jan-1970)." " Default value is 0 for transactions without locktime") confirmations = Column(Integer, default=0, doc="Number of confirmation when this transaction is included in a block. " "Default is 0: unconfirmed") block_height = Column(Integer, index=True, doc="Height of block this transaction is included in") network_name = Column(String(20), doc="Blockchain network name of this transaction") fee = Column(BigInteger, doc="Transaction fee") nodes = relationship("DbCacheTransactionNode", cascade="all,delete", doc="List of all inputs and outputs as DbCacheTransactionNode objects") order_n = Column(Integer, doc="Order of transaction in block") witness_type = Column(Enum(WitnessTypeTransactions), default=WitnessTypeTransactions.legacy, doc="Transaction type enum: legacy or segwit")
[docs]class DbCacheAddress(Base): """ Address Cache Table Stores transactions and unspent outputs (UTXO's) per address """ __tablename__ = 'cache_address' address = Column(String(255), primary_key=True, doc="Address string base32 or base58 encoded") network_name = Column(String(20), doc="Blockchain network name of this transaction") balance = Column(BigInteger, default=0, doc="Total balance of UTXO's linked to this key") last_block = Column(Integer, doc="Number of last updated block") last_txid = Column(LargeBinary(32), doc="Transaction ID of latest transaction in cache") n_utxos = Column(Integer, doc="Total number of UTXO's for this address") n_txs = Column(Integer, doc="Total number of transactions for this address")
[docs]class DbCacheBlock(Base): """ Block Cache Table Stores block headers """ __tablename__ = 'cache_blocks' height = Column(Integer, primary_key=True, doc="Height or sequence number for this block") block_hash = Column(LargeBinary(32), index=True, doc="Hash of this block") network_name = Column(String(20), doc="Blockchain network name") version = Column(BigInteger, doc="Block version to specify which features are used (hex)") prev_block = Column(LargeBinary(32), doc="Block hash of previous block") merkle_root = Column(LargeBinary(32), doc="Merkle root used to validate transaction in block") time = Column(BigInteger, doc="Timestamp to indicated when block was created") bits = Column(BigInteger, doc="Encoding for proof-of-work, used to determine target and difficulty") nonce = Column(BigInteger, doc="Nonce (number used only once or n-once) is used to create different block hashes") tx_count = Column(Integer, doc="Number of transactions included in this block")
[docs]class DbCacheVars(Base): """ Table to store various blockchain related variables """ __tablename__ = 'cache_variables' varname = Column(String(50), primary_key=True, doc="Variable unique name") network_name = Column(String(20), primary_key=True, doc="Blockchain network name of this transaction") value = Column(String(255), doc="Value of variable") type = Column(String(20), doc="Type of variable: int, string or float") expires = Column(DateTime, doc="Datetime value when variable expires")