simplecache.py 文件源码

def _do_cleanup(self):
        '''perform cleanup task'''
        if self._exit or self._monitor.abortRequested():
            return
        self._busy_tasks.append(__name__)
        cur_time = datetime.datetime.now()
        cur_timestamp = self._get_timestamp(cur_time)
        self._log_msg("Running cleanup...")
        if self._win.getProperty("simplecachecleanbusy"):
            return
        self._win.setProperty("simplecachecleanbusy", "busy")

        query = "SELECT id, expires FROM simplecache"
        for cache_data in self._execute_sql(query).fetchall():
            cache_id = cache_data[0]
            cache_expires = cache_data[1]
            if self._exit or self._monitor.abortRequested():
                return
            # always cleanup all memory objects on each interval
            self._win.clearProperty(cache_id.encode("utf-8"))
            # clean up db cache object only if expired
            if cache_expires < cur_timestamp:
                query = 'DELETE FROM simplecache WHERE id = ?'
                self._execute_sql(query, (cache_id,))
                self._log_msg("delete from db %s" % cache_id)

        # compact db
        self._execute_sql("VACUUM")

        # remove task from list
        self._busy_tasks.remove(__name__)
        self._win.setProperty("simplecache.clean.lastexecuted", repr(cur_time))
        self._win.clearProperty("simplecachecleanbusy")
        self._log_msg("Auto cleanup done")