def handle_message()

in redis/client.py [0:0]

• 59 lines of code
• 20 McCabe index (conditional complexity)

    def handle_message(self, response, ignore_subscribe_messages=False):
        """
        Parses a pub/sub message. If the channel or pattern was subscribed to
        with a message handler, the handler is invoked instead of a parsed
        message being returned.
        """
        if response is None:
            return None
        if isinstance(response, bytes):
            response = [b"pong", response] if response != b"PONG" else [b"pong", b""]
        message_type = str_if_bytes(response[0])
        if message_type == "pmessage":
            message = {
                "type": message_type,
                "pattern": response[1],
                "channel": response[2],
                "data": response[3],
            }
        elif message_type == "pong":
            message = {
                "type": message_type,
                "pattern": None,
                "channel": None,
                "data": response[1],
            }
        else:
            message = {
                "type": message_type,
                "pattern": None,
                "channel": response[1],
                "data": response[2],
            }

        # if this is an unsubscribe message, remove it from memory
        if message_type in self.UNSUBSCRIBE_MESSAGE_TYPES:
            if message_type == "punsubscribe":
                pattern = response[1]
                if pattern in self.pending_unsubscribe_patterns:
                    self.pending_unsubscribe_patterns.remove(pattern)
                    self.patterns.pop(pattern, None)
            elif message_type == "sunsubscribe":
                s_channel = response[1]
                if s_channel in self.pending_unsubscribe_shard_channels:
                    self.pending_unsubscribe_shard_channels.remove(s_channel)
                    self.shard_channels.pop(s_channel, None)
            else:
                channel = response[1]
                if channel in self.pending_unsubscribe_channels:
                    self.pending_unsubscribe_channels.remove(channel)
                    self.channels.pop(channel, None)
            if not self.channels and not self.patterns and not self.shard_channels:
                # There are no subscriptions anymore, set subscribed_event flag
                # to false
                self.subscribed_event.clear()

        if message_type in self.PUBLISH_MESSAGE_TYPES:
            # if there's a message handler, invoke it
            if message_type == "pmessage":
                handler = self.patterns.get(message["pattern"], None)
            elif message_type == "smessage":
                handler = self.shard_channels.get(message["channel"], None)
            else:
                handler = self.channels.get(message["channel"], None)
            if handler:
                handler(message)
                return None
        elif message_type != "pong":
            # this is a subscribe/unsubscribe message. ignore if we don't
            # want them
            if ignore_subscribe_messages or self.ignore_subscribe_messages:
                return None

        return message