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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, QueuePool
38 from sqlalchemy.interfaces import PoolListener
41 class DBWrapper(object):
42 """Database connection wrapper."""
44 def __init__(self, db):
45 if db.startswith('sqlite://'):
46 class ForeignKeysListener(PoolListener):
47 def connect(self, dbapi_con, con_record):
48 db_cursor = dbapi_con.execute('pragma foreign_keys=ON;')
49 db_cursor = dbapi_con.execute(
50 'pragma case_sensitive_like=ON;')
51 self.engine = create_engine(db, connect_args={'check_same_thread': False}, poolclass=NullPool, listeners=[ForeignKeysListener()])
52 #elif db.startswith('mysql://'):
53 # db = '%s?charset=utf8&use_unicode=0' %db
54 # self.engine = create_engine(db, convert_unicode=True)
56 #self.engine = create_engine(db, pool_size=0, max_overflow=-1)
57 self.engine = create_engine(db, poolclass=NullPool)
58 self.engine.echo = True
59 self.engine.echo_pool = False
60 self.conn = self.engine.connect()
67 self.trans = self.conn.begin()