mqtt: add support for publishing klipper status updates

Signed-off-by:  Eric Callahan <arksine.code@gmail.com>

moonraker/components/mqtt.py

@@ -12,7 +12,7 @@ import json
 import pathlib
 from collections import deque
 import paho.mqtt.client as paho_mqtt
-from websockets import WebRequest, JsonRPC, APITransport
+from websockets import Subscribable, WebRequest, JsonRPC, APITransport
 
 # Annotation imports
 from typing import (
@@ -131,7 +131,7 @@ class AIOHelper:
         logging.info("MQTT Misc Loop Complete")
 
 
-class MQTTClient(APITransport):
+class MQTTClient(APITransport, Subscribable):
     def __init__(self, config: ConfigHelper) -> None:
         self.server = config.get_server()
         self.event_loop = self.server.get_event_loop()
@@ -186,11 +186,20 @@ class MQTTClient(APITransport):
             self._handle_subscription_request,
             transports=["http", "websocket"])
 
-
         # Subscribe to API requests
         self.json_rpc = JsonRPC(transport="MQTT")
         self.api_request_topic = f"{self.instance_name}/moonraker/api/request"
         self.api_resp_topic = f"{self.instance_name}/moonraker/api/response"
+        self.klipper_status_topic = f"{self.instance_name}/klipper/status"
+        status_cfg = config.get("status_objects", None)
+        self.status_objs: Dict[str, Any] = {}
+        if status_cfg is not None:
+            status_cfg = status_cfg.strip()
+            self.status_objs = {k.strip(): None for k in status_cfg.split('\n')
+                                if k.strip()}
+            self.server.register_event_handler("server:klippy_identified",
+                                               self._handle_klippy_identified)
+
         self.timestamp_deque: Deque = deque(maxlen=20)
         self.api_qos = config.getint('api_qos', self.qos)
         if config.getboolean("enable_moonraker_api", True):
@@ -233,6 +242,15 @@ class MQTTClient(APITransport):
         self.client.socket().setsockopt(
             socket.SOL_SOCKET, socket.SO_SNDBUF, 2048)
 
+    async def _handle_klippy_identified(self) -> None:
+        if self.status_objs:
+            args = {'objects': self.status_objs}
+            try:
+                await self.server.make_request(
+                    WebRequest("objects/subscribe", args, conn=self))
+            except self.server.error:
+                pass
+
     def _on_message(self,
                     client: str,
                     user_data: Any,
@@ -574,6 +592,15 @@ class MQTTClient(APITransport):
             else:
                 self.timestamp_deque.append(ts)
 
+    def send_status(self,
+                    status: Dict[str, Any],
+                    eventtime: float
+                    ) -> None:
+        if not status:
+            return
+        payload = {'eventtime': eventtime, 'status': status}
+        self.publish_topic(self.klipper_status_topic, payload)
+
     async def close(self) -> None:
         if self.reconnect_task is not None:
             self.reconnect_task.cancel()