py.lib: db/sqlite.py annotate

* db/sqlite.py: Импортируем полезные классы для реакции на ошибки

awgur@13	1 # coding: utf-8
awgur@13	2 import sqlite3
awgur@14	3 from sqlite3 import Error, IntegrityError
awgur@13	4
awgur@13	5 class DB:
awgur@13	6 def __init__(self, db_file):
awgur@13	7 self._con = sqlite3.connect(db_file)
awgur@13	8 self._ex = self._con.execute
awgur@13	9 self.commit = self._con.commit
awgur@13	10 self.rollback = self._con.rollback
awgur@13	11
awgur@13	12 # DB PREP
awgur@13	13 self._ex("PRAGMA journal=WAL")
awgur@13	14 self.commit()
awgur@13	15
awgur@13	16 def __del__(self):
awgur@13	17 try:
awgur@13	18 self.rollback()
awgur@13	19 self._con.close()
awgur@13	20 except:
awgur@13	21 pass
awgur@13	22
awgur@13	23 def __call__(self, a, *kwa):
awgur@13	24 cur = self._con.cursor()
awgur@13	25 cur.execute(a, *kwa)
awgur@13	26 return cur
awgur@13	27
awgur@13	28 def cq(self, a, *wa):
awgur@13	29 try:
awgur@13	30 res = self(a, *wa)
awgur@13	31 self.commit()
awgur@13	32 return res
awgur@14	33 except Error as e:
awgur@13	34 self.rollback()
awgur@13	35 raise e

py.lib