Handler

def add_call(
    self,
    *,
    handler: HandlerCallWrapper[Message, P_HandlerParams, T_HandlerReturn],
    dependant: CallModel[P_HandlerParams, T_HandlerReturn],
    parser: CustomParser[Union[Message, Tuple[Message, ...]], KafkaMessage],
    decoder: Optional[CustomDecoder[KafkaMessage]],
    filter: Union[
        Filter[KafkaMessage],
        Filter[StreamMessage[Tuple[Message, ...]]],
    ],
    middlewares: Optional[Sequence[Callable[[Message], BaseMiddleware]]],
) -> None:
    """Adds a call to the handler.

    Args:
        handler: The handler function to be called.
        dependant: The dependant model.
        parser: Optional custom parser for parsing the input.
        decoder: Optional custom decoder for decoding the input.
        filter: The filter for filtering the input.
        middlewares: Optional sequence of middlewares to be applied.

    Returns:
        None

    """
    parser_ = resolve_custom_func(  # type: ignore[type-var]
        parser,  # type: ignore[arg-type]
        (
            AsyncConfluentParser.parse_message_batch  # type: ignore[arg-type]
            if self.batch
            else AsyncConfluentParser.parse_message
        ),
    )
    decoder_ = resolve_custom_func(
        decoder,  # type: ignore[arg-type]
        (
            AsyncConfluentParser.decode_message_batch  # type: ignore[arg-type]
            if self.batch
            else AsyncConfluentParser.decode_message
        ),
    )
    super().add_call(
        handler=handler,
        parser=parser_,
        decoder=decoder_,
        filter=filter,  # type: ignore[arg-type]
        dependant=dependant,
        middlewares=middlewares,
    )

async def close(self) -> None:
    await super().close()

    if self.consumer is not None:
        await self.consumer.stop()
        self.consumer = None

    if self.task is not None:
        self.task.cancel()
        self.task = None

@override
async def consume(self, msg: MsgType) -> SendableMessage:  # type: ignore[override]
    """Consume a message asynchronously.

    Args:
        msg: The message to be consumed.

    Returns:
        The sendable message.

    Raises:
        StopConsume: If the consumption needs to be stopped.

    Raises:
        Exception: If an error occurs during consumption.

    """
    result: Optional[WrappedReturn[SendableMessage]] = None
    result_msg: SendableMessage = None

    if not self.running:
        return result_msg

    log_context_tag: Optional["Token[Any]"] = None
    async with AsyncExitStack() as stack:
        stack.enter_context(self.lock)

        stack.enter_context(context.scope("handler_", self))

        gl_middlewares: List[BaseMiddleware] = [
            await stack.enter_async_context(m(msg)) for m in self.global_middlewares
        ]

        logged = False
        processed = False
        for handler, filter_, parser, decoder, middlewares, _ in self.calls:
            local_middlewares: List[BaseMiddleware] = [
                await stack.enter_async_context(m(msg)) for m in middlewares
            ]

            all_middlewares = gl_middlewares + local_middlewares

            # TODO: add parser & decoder caches
            message = await parser(msg)

            if not logged:  # pragma: no branch
                log_context_tag = context.set_local(
                    "log_context",
                    self.log_context_builder(message),
                )

            message.decoded_body = await decoder(message)
            message.processed = processed

            if await filter_(message):
                assert (  # nosec B101
                    not processed
                ), "You can't process a message with multiple consumers"

                try:
                    async with AsyncExitStack() as consume_stack:
                        for m_consume in all_middlewares:
                            message.decoded_body = (
                                await consume_stack.enter_async_context(
                                    m_consume.consume_scope(message.decoded_body)
                                )
                            )

                        result = await cast(
                            Awaitable[Optional[WrappedReturn[SendableMessage]]],
                            handler.call_wrapped(message),
                        )

                    if result is not None:
                        result_msg, pub_response = result

                        # TODO: suppress all publishing errors and raise them after all publishers will be tried
                        for publisher in (pub_response, *handler._publishers):
                            if publisher is not None:
                                async with AsyncExitStack() as pub_stack:
                                    result_to_send = result_msg

                                    for m_pub in all_middlewares:
                                        result_to_send = (
                                            await pub_stack.enter_async_context(
                                                m_pub.publish_scope(result_to_send)
                                            )
                                        )

                                    await publisher.publish(
                                        message=result_to_send,
                                        correlation_id=message.correlation_id,
                                    )

                except StopConsume:
                    await self.close()
                    handler.trigger()

                except HandlerException as e:  # pragma: no cover
                    handler.trigger()
                    raise e

                except Exception as e:
                    handler.trigger(error=e)
                    raise e

                else:
                    handler.trigger(result=result[0] if result else None)
                    message.processed = processed = True
                    if IS_OPTIMIZED:  # pragma: no cover
                        break

        assert not self.running or processed, "You have to consume message"  # nosec B101

    if log_context_tag is not None:
        context.reset_local("log_context", log_context_tag)

    return result_msg

def get_payloads(self) -> List[Tuple[AnyDict, str]]:
    """Get the payloads of the handler."""
    payloads: List[Tuple[AnyDict, str]] = []

    for h, _, _, _, _, dep in self.calls:
        body = parse_handler_params(
            dep,
            prefix=f"{self._title or self.call_name}:Message",
        )
        payloads.append(
            (
                body,
                to_camelcase(unwrap(h._original_call).__name__),
            ),
        )

    return payloads

@staticmethod
def get_routing_hash(topics: Sequence[str], group_id: Optional[str] = None) -> str:
    return "".join((*topics, group_id or ""))

@abstractproperty
def name(self) -> str:
    """Returns the name of the API operation."""
    raise NotImplementedError()

def schema(self) -> Dict[str, Channel]:
    if not self.include_in_schema:
        return {}

    channels = {}

    payloads = self.get_payloads()

    for t in self.topics:
        handler_name = self._title or f"{t}:{self.call_name}"
        channels[handler_name] = Channel(
            description=self.description,
            subscribe=Operation(
                message=Message(
                    title=f"{handler_name}:Message",
                    payload=resolve_payloads(payloads),
                    correlationId=CorrelationId(
                        location="$message.header#/correlation_id"
                    ),
                ),
            ),
            bindings=ChannelBinding(kafka=kafka.ChannelBinding(topic=t)),
        )

    return channels

@override
async def start(  # type: ignore[override]
    self,
    **consumer_kwargs: Unpack[ConsumerConnectionParams],
) -> None:
    """Start the consumer.

    Args:
        **consumer_kwargs: Additional keyword arguments to pass to the consumer.

    Returns:
        None

    """
    self.consumer = consumer = self.builder(
        *self.topics,
        group_id=self.group_id,
        client_id=self.client_id,
        **consumer_kwargs,
    )
    await consumer.start()
    self.task = asyncio.create_task(self._consume())
    await super().start()