use protocol decoders for all message types (even custom ones)

meshtastic/__init__.py

@@ -101,12 +101,46 @@ class KnownProtocol(NamedTuple):
     """Used to automatically decode known protocol payloads"""
     name: str
     # portnum: int, now a key
-    protobufFactory: Callable
+    protobufFactory: Callable = None # If set, will be called to prase as a protocol buffer
+    onReceive: Callable = None # If set, invoked as onReceive(interface, packet)
+
+def _onTextReceive(iface, asDict):
+    """Special text auto parsing for received messages"""
+    # We don't throw if the utf8 is invalid in the text message.  Instead we just don't populate
+    # the decoded.data.text and we log an error message.  This at least allows some delivery to
+    # the app and the app can deal with the missing decoded representation.
+    #
+    # Usually btw this problem is caused by apps sending binary data but setting the payload type to
+    # text.
+    try:
+        asDict["decoded"]["text"] = meshPacket.decoded.payload.decode(
+            "utf-8")
+    except Exception as ex:
+        logging.error(f"Malformatted utf8 in text message: {ex}")
+
+def _onPositionReceive(iface, asDict):
+    """Special auto parsing for received messages"""
+    p = asDict["decoded"]["position"]
+    iface._fixupPosition(p)
+    # update node DB as needed
+    iface._getOrCreateByNum(asDict["from"])["position"] = p
+
+def _onNodeInfoReceive(iface, asDict):
+    """Special auto parsing for received messages"""
+    p = asDict["decoded"]["user"]
+    # decode user protobufs and update nodedb, provide decoded version as "position" in the published msg
+    # update node DB as needed
+    n = iface._getOrCreateByNum(asDict["from"])
+    n["user"] = p
+    # We now have a node ID, make sure it is uptodate in that table
+    iface.nodes[p["id"]] = n
+
 
 """Well known message payloads can register decoders for automatic protobuf parsing"""
 protocols = {
-    portnums_pb2.PortNum.POSITION_APP: KnownProtocol("position", mesh_pb2.Position),
-    portnums_pb2.PortNum.NODEINFO_APP: KnownProtocol("user", mesh_pb2.User),
+    portnums_pb2.PortNum.TEXT_MESSAGE_APP: KnownProtocol("text", onReceive=_onTextReceive),
+    portnums_pb2.PortNum.POSITION_APP: KnownProtocol("position", mesh_pb2.Position, _onPositionReceive),
+    portnums_pb2.PortNum.NODEINFO_APP: KnownProtocol("user", mesh_pb2.User, _onNodeInfoReceive),
     portnums_pb2.PortNum.ADMIN_APP: KnownProtocol("admin", admin_pb2.AdminMessage),
     portnums_pb2.PortNum.ENVIRONMENTAL_MEASUREMENT_APP: KnownProtocol("environmental", environmental_measurement_pb2.EnvironmentalMeasurement),
     portnums_pb2.PortNum.REMOTE_HARDWARE_APP: KnownProtocol("remotehw", remote_hardware_pb2.HardwareMessage)
@@ -541,22 +575,6 @@ class MeshInterface:
 
         topic = f"meshtastic.receive.data.{portnum}"
 
-        # For text messages, we go ahead and decode the text to ascii for our users
-        if portnum == portnums_pb2.PortNum.Name(portnums_pb2.PortNum.TEXT_MESSAGE_APP):
-            topic = "meshtastic.receive.text"
-
-            # We don't throw if the utf8 is invalid in the text message.  Instead we just don't populate
-            # the decoded.data.text and we log an error message.  This at least allows some delivery to
-            # the app and the app can deal with the missing decoded representation.
-            #
-            # Usually btw this problem is caused by apps sending binary data but setting the payload type to
-            # text.
-            try:
-                asDict["decoded"]["text"] = meshPacket.decoded.payload.decode(
-                    "utf-8")
-            except Exception as ex:
-                logging.error(f"Malformatted utf8 in text message: {ex}")
-
         # decode position protobufs and update nodedb, provide decoded version as "position" in the published msg
         # move the following into a 'decoders' API that clients could register?
         portNumInt = meshPacket.decoded.portnum # we want portnum as an int
@@ -564,23 +582,17 @@ class MeshInterface:
         p = None # The decoded protobuf as a dictionary (if we understand this message)
         if handler is not None:
             topic = f"meshtastic.receive.{handler.name}"
-            pb = handler.protobufFactory()
-            pb.ParseFromString(meshPacket.decoded.payload)
-            p = google.protobuf.json_format.MessageToDict(pb)
-            asDict["decoded"][handler.name] = p
 
-        if portNumInt == portnums_pb2.PortNum.POSITION_APP:
-            self._fixupPosition(p)
-            # update node DB as needed
-            self._getOrCreateByNum(asDict["from"])["position"] = p
+            # Convert to protobuf if possible
+            if handler.protobufFactory is not None:
+                pb = handler.protobufFactory()
+                pb.ParseFromString(meshPacket.decoded.payload)
+                p = google.protobuf.json_format.MessageToDict(pb)
+                asDict["decoded"][handler.name] = p
 
-        # decode user protobufs and update nodedb, provide decoded version as "position" in the published msg
-        if portNumInt == portnums_pb2.PortNum.NODEINFO_APP:
-            # update node DB as needed
-            n = self._getOrCreateByNum(asDict["from"])
-            n["user"] = p
-            # We now have a node ID, make sure it is uptodate in that table
-            self.nodes[p["id"]] = n
+            # Call specialized onReceive if necessary
+            if handler.onReceive is not None:
+                handler.onReceive(self, asDict)
 
         logging.debug(f"Publishing topic {topic}")
         catchAndIgnore(f"publishing {topic}", lambda: pub.sendMessage(