How do I invoke method with callback?

[luiey]

I can connect to my service hub, calling method with parameter and it will delegate the trigger from signal R hub.

But how do I invoke and get the result returned from the hub directly? I'm currently able to doing it in .NET to get the response. And I stuck on Python application.

[SmsS4]

Hi you have to change Hub class like this:

class HubServerIndexer:
    """
    HubServer won't return index of message
    but sometimes we need it
    """

    def __init__(self, name, connection, hub):
        self.name = name
        self.__connection = connection
        self.__hub = hub
        self.wait_for_result: Dict[int, Event] = {}

    def indexed_invoke(self, method, wait_for_result: bool, *data) -> int:
        """
        Invoke a method on server and returns the result
        """
        index = self.__connection.increment_send_counter()
        if wait_for_result:
            self.wait_for_result[index] = threading.Event()
        self.__connection.send({"H": self.name, "M": method, "A": data, "I": index})
        return index

session = Session()
connection = Connection(url, session)
connection.received += receive
hub = self._connection.register_hub(hub_name)
hub.server = HubServerIndexer(hub.name, connection, hub)
received_messages: Dict[int, Any] = {}

def receive(self, **kwargs) -> None:
    if "I" not in kwargs:
        return
    index = int(kwargs.get("I"))
    if index in hub.server.wait_for_result:
        hub.server.wait_for_result.pop(index).set()
        received_messages[index] = kwargs.get("R")

def invoke_and_get_result(self, method: str, *args) -> Any:
    """
    Invoke a method on hub and return server response
    """
    index = hub.server.indexed_invoke(method, True, *args)
    event: Optional[Event] = hub.server.wait_for_result.get(index, None)
    if event:
        event.wait(timeout=60)
    return self.received_messages.pop(index)

call invoke_and_get_result(method_name, *method_args) to get response