power: use a mutex to prevent concurrent device requests

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

moonraker/components/power.py

@@ -13,7 +13,7 @@ import socket
 import gpiod
 from tornado.ioloop import IOLoop
 from tornado.iostream import IOStream
-from tornado import gen
+from tornado.locks import Lock
 from tornado.httpclient import AsyncHTTPClient
 from tornado.escape import json_decode
 
@@ -238,6 +238,7 @@ class HTTPDevice(PowerDevice):
                  default_user=None, default_password=None):
         super().__init__(config)
         self.client = AsyncHTTPClient()
+        self.request_mutex = Lock()
         self.addr = config.get("address")
         self.port = config.getint("port", default_port)
         self.user = config.get("user", default_user)
@@ -265,6 +266,7 @@ class HTTPDevice(PowerDevice):
             "_send_status_request must be implemented by children")
 
     async def refresh_status(self):
+        async with self.request_mutex:
             try:
                 state = await self._send_status_request()
             except Exception:
@@ -275,6 +277,7 @@ class HTTPDevice(PowerDevice):
             self.state = state
 
     async def set_power(self, state):
+        async with self.request_mutex:
             try:
                 state = await self._send_power_request(state)
             except Exception:
@@ -381,6 +384,7 @@ class TPLinkSmartPlug(PowerDevice):
     START_KEY = 0xAB
     def __init__(self, config):
         super().__init__(config)
+        self.request_mutex = Lock()
         self.addr = config.get("address").split('/')
         self.port = config.getint("port", 9999)
 
@@ -448,6 +452,7 @@ class TPLinkSmartPlug(PowerDevice):
         await self.refresh_status()
 
     async def refresh_status(self):
+        async with self.request_mutex:
             try:
                 res = await self._send_tplink_command("info")
                 if len(self.addr) == 2:
@@ -464,6 +469,7 @@ class TPLinkSmartPlug(PowerDevice):
             self.state = "on" if state else "off"
 
     async def set_power(self, state):
+        async with self.request_mutex:
             try:
                 res = await self._send_tplink_command(state)
                 err = res['system']['set_relay_state']['err_code']