9u670TAc

1#!/usr/bin/env python3
2import sqlite3
3
4
5class BaseCache:
6	def __init__(self, filename, table):
7		self.filename = filename
8		self.table = table
9		self.db_con = sqlite3.connect(filename)
10		self.create_table()
11
12	def __str__(self):
13		return '{}.{}'.format(self.filename, self.table)
14
15	def __len__(self):
16		cur = self.db_con.cursor()
17		cur.execute("SELECT COUNT(*) FROM {}".format(self.table))
18		return cur.fetchone()[0]
19
20	def __delitem__(self, key):
21		cur = self.db_con.cursor()
22		req = "DELETE FROM {} WHERE key=?".format(self.table)
23		cur.execute(req, (key,))
24		self.db_con.commit()
25
26	def __getitem__(self, key):
27		cur = self.db_con.cursor()
28		req = "SELECT value FROM {} WHERE key=?".format(self.table)
29		cur.execute(req, (key,))
30		res = cur.fetchone()
31		if res:
32			return res[0]
33
34	def __setitem__(self, key, value):
35		cur = self.db_con.cursor()
36		value = str(value)
37		try:
38			req = "INSERT INTO {} VALUES (?,?)".format(self.table)
39			cur.execute(req, (key, value))
40		except sqlite3.IntegrityError:
41			req = "UPDATE {} SET value=? WHERE key=?".format(self.table)
42			cur.execute(req, (value, key))
43		self.db_con.commit()
44
45	def __enter__(self):
46		return self
47
48	def __exit__(self, type, value, traceback):
49		self.close()
50
51	def create_table(self):
52		cur = self.db_con.cursor()
53		req = 'CREATE TABLE IF NOT EXISTS {}'.format(self.table)
54		col = '(key TEXT PRIMARY KEY, value TEXT)'
55		cur.execute(req + ' ' + col)
56		self.db_con.commit()
57
58	def close(self):
59		self.db_con.close()
60
61
62if __name__ == '__main__':
63	with BaseCache('test.db', 'cache') as cache:
64		cache['version'] = '0.1'
65		cache['lang'] = 'fr'
66		print(cache['version'])
67		print(cache['lang'])
68		del cache['lang']
69		print(cache['lang'])