create parent class for sql databases

electrum/lnwatcher.py

@@ -11,9 +11,14 @@ from collections import defaultdict
 import asyncio
 from enum import IntEnum, auto
 from typing import NamedTuple, Dict
-
 import jsonrpclib
 
+from sqlalchemy import Column, ForeignKey, Integer, String, DateTime, Boolean
+from sqlalchemy.orm.query import Query
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.sql import not_, or_
+from .sql_db import SqlDB, sql
+
 from .util import PrintError, bh2u, bfh, log_exceptions, ignore_exceptions
 from . import wallet
 from .storage import WalletStorage
@@ -37,14 +42,6 @@ class TxMinedDepth(IntEnum):
     FREE = auto()
 
 
-from sqlalchemy import create_engine, Column, ForeignKey, Integer, String, DateTime, Boolean
-from sqlalchemy.pool import StaticPool
-from sqlalchemy.orm import sessionmaker
-from sqlalchemy.orm.query import Query
-from sqlalchemy.ext.declarative import declarative_base
-from sqlalchemy.sql import not_, or_
-from sqlalchemy.orm import scoped_session
-
 Base = declarative_base()
 
 class SweepTx(Base):
@@ -60,42 +57,11 @@ class ChannelInfo(Base):
     outpoint = Column(String(34))
 
 
-class SweepStore(PrintError):
+
+class SweepStore(SqlDB):
 
     def __init__(self, path, network):
-        PrintError.__init__(self)
-        self.path = path
-        self.network = network
-        self.db_requests = queue.Queue()
-        threading.Thread(target=self.sql_thread).start()
-
-    def sql_thread(self):
-        engine = create_engine('sqlite:///' + self.path, pool_reset_on_return=None, poolclass=StaticPool)
-        DBSession = sessionmaker(bind=engine, autoflush=False)
-        self.DBSession = DBSession()
-        if not os.path.exists(self.path):
-            Base.metadata.create_all(engine)
-        while self.network.asyncio_loop.is_running():
-            try:
-                future, func, args, kwargs = self.db_requests.get(timeout=0.1)
-            except queue.Empty:
-                continue
-            try:
-                result = func(self, *args, **kwargs)
-            except BaseException as e:
-                future.set_exception(e)
-                continue
-            future.set_result(result)
-        # write
-        self.DBSession.commit()
-        self.print_error("SQL thread terminated")
-
-    def sql(func):
-        def wrapper(self, *args, **kwargs):
-            f = concurrent.futures.Future()
-            self.db_requests.put((f, func, args, kwargs))
-            return f.result(timeout=10)
-        return wrapper
+        super().__init__(network, path, Base)
 
     @sql
     def get_sweep_tx(self, funding_outpoint, prev_txid):