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34 from sqlalchemy import create_engine
35 #from sqlalchemy.event import listen
36 from sqlalchemy.engine import Engine
37 from sqlalchemy.pool import NullPool
38 from sqlalchemy.interfaces import PoolListener
40 class DBWrapper(object):
41 """Database connection wrapper."""
43 def __init__(self, db):
44 if db.startswith('sqlite://'):
45 class ForeignKeysListener(PoolListener):
46 def connect(self, dbapi_con, con_record):
47 db_cursor = dbapi_con.execute('pragma foreign_keys=ON')
48 self.engine = create_engine(db, connect_args={'check_same_thread': False}, poolclass=NullPool, listeners=[ForeignKeysListener()])
50 self.engine = create_engine(db)
51 #self.engine.echo = True
52 self.conn = self.engine.connect()
56 self.trans = self.conn.begin()