cache.py 文件源码

def get(self, key, timeout=None):
        """Given a key, returns an element from the redis table"""
        key = self.pre_identifier + key
        # Check to see if we have this key
        unpickled_entry = self.client.get(key)
        if not unpickled_entry:
            # No hit, return nothing
            return None

        entry = pickle.loads(unpickled_entry)
        # Use provided timeout in arguments if provided
        # otherwise use the one provided during init.
        if timeout is None:
            timeout = self.timeout

        # Make sure entry is not expired
        if self._is_expired(entry, timeout):
            # entry expired, delete and return nothing
            self.delete_entry(key)
            return None
        # entry found and not expired, return it
        return entry[1]