sqlite数据库保存聊天记录
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最近正在开发一个即时聊天系统----Pian Communicator，该项目是基于XMPP协议，使用Python+wxPython+xmpp.py开发，由于都是深夜奋战，项目进展也比较慢，目前正在开发聊天功能。聊天功能中还需要保护聊天记录的保存，就像QQ一样，我们可以浏览历史聊天记录。有些即时聊天系统的聊天记录也有采用xml文件记录的，但是xml文件毕竟没有数据库那么容易检索数据，因此我这里打算采用sqlite数据库来存储，并且Python本身就自带了对sqlite的支持。
首先先定义了记录和查询接口，比较目前确定是使用sqlite来记录，但以后也有可能使用xml或其它方式来记录的可能，因此这里定义一个抽象，以便以后进行扩展。接口主要的方法为read和write方法，分别用于读，写记录，记录的内容暂时只有talk（发言者）, nickname（发言者的别名）, typ（记录类别，包括msg, file等），msg（内容），tm（时间）。另外为了避免忘记调用close方法，特地定义了__del__方法，并且该方法会在类被垃圾回收时调用。代码如下：
class History(object):
def __init__(self, jid, to, path):
self.__jid = jid
self.__to = to
self.__path = path
self.__opened = False
if not os.path.exists(path):
os.mkdir(path)
def get_jid(self): return self.__jid
def get_to(self): return self.__to
def get_path(self): return self.__path
def open(self): raise NotImplementedError()
def read(self): raise NotImplementedError()
def write(self, talk, nickname, typ, msg, tm): raise NotImplementedError()
def close(self): raise NotImplementedError()
def __del__(self):
if self.__opened:
self.close()采用sqlite数据库存储记录的具体类，如下实现：
class SqliteStorageHistory(History):
def __init__(self, jid, to, path):
super(SqliteStorageHistory, self).__init__(jid, to, path)
_dir = os.path.join(path, self.get_jid())
if not os.path.exists(_dir):
os.mkdir(_dir)
self.dbname = os.path.join(path, self.get_jid(), 'history.db')
self.__connection = None
self.__cursor = None
def open(self):
has = True
if not os.path.exists(self.dbname):
has = False
self.__connection = sqlite3.connect(self.dbname)
self.__cursor = self.__connection.cursor()
if not has:
self.__cursor.execute('''create table histories (_to text, talk text, nick text, typ text, msg text,
datetime datetime)''')
self.__connection.commit()
self.__opened = True
def read(self):
if self.__cursor == None or self.__connection == None:
raise HistoryError('Please Open connection.')
for row in self.__cursor.execute("select * from histories where _to=?", (self.get_to(),)):
yield row
def write(self, talk, nickname, typ, msg, tm):
if self.__cursor == None or self.__connection == None:
raise HistoryError('Please Open connection.')
self.__cursor.execute('insert into histories (_to, talk, nick, typ, msg, datetime) values (?, ?, ?, ?, ?,
?)', \
(self.get_to(), talk, nickname, typ, msg, str(tm),))
self.__connection.commit()
def close(self):
if not self.__opened:
return
if not self.__cursor:
try:
self.__cursor.close()
del self.__cursor
except: pass
if not self.__connection:
try:
self.__connection.close()
del self.__connection
except: pass
self.__opened = False测试代码为：
if __name__ == '__main__':
sql = SqliteStorageHistory('[email protected]','[email protected]', 'c:\\his2')
sql.open()
sql.write('[email protected]', 'Wang, 2Xiao', 'msg', 'Hi, What are you doing?',
datetime.datetime.now())
sql.write('[email protected]', 'Zhang, Guangbo', 'msg', 'Hi, Nothing.', datetime.datetime.now())
for row in sql.read():
print row
sql.close()输出结果:
(u'[email protected]', u'[email protected]', u'Wang, 2Xiao', u'msg', u'Hi, What are you
doing?', u'2013-01-29 16:21:04.324000')
(u'[email protected]', u'[email protected]', u'Zhang, Guangbo', u'msg', u'Hi, Nothing.', u'2013
-01-29 16:21:04.417000')