on_message_in Event

Fired when an incoming message has been received and/or fully acknowledged.

Syntax

class MQTTMessageInEventParams(object):
  @property
  def packet_id() -> int: ...
  @property
  def topic() -> str: ...
  @property
  def qos() -> int: ...
  @property
  def message() -> bytes: ...
  @property
  def retained() -> bool: ...
  @property
  def duplicate() -> bool: ...

# In class MQTT:
@property
def on_message_in() -> Callable[[MQTTMessageInEventParams], None]: ...
@on_message_in.setter
def on_message_in(event_hook: Callable[[MQTTMessageInEventParams], None]) -> None: ...

Remarks

The on_message_in event fires once for each incoming message either immediately after it is received (QoS 0), or after it has been fully acknowledged (QoS 1 and 2).

• PacketId: The message packet Id. This will always be -1 if QOS is 0.
• Topic: The message's topic string.
• QOS: The message's QoS level.
• Message: The message data.
• Retained: Whether or not this message was received as a result of subscribing to a topic.
• Duplicate: Whether or not the server has indicated that this message is a duplicate of another message sent previously.

Refer to on_message_ack for more information about QoS 1 and 2 message processing steps.

// MessageIn event handler.
mqtt1.OnMessageIn += (s, e) => {
  Console.WriteLine("Received message from topic '" + e.Topic + "' with QoS " + e.QOS + ":");
  Console.WriteLine(e.Message);
};