power: add support for tplink smartplug (Kasa) devices

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

moonraker/plugins/power.py

@@ -7,8 +7,12 @@
 import logging
 import os
 import asyncio
+import json
+import struct
+import socket
 import gpiod
 from tornado.ioloop import IOLoop
+from tornado.iostream import IOStream
 from tornado import gen
 
 class PrinterPower:
@@ -39,6 +43,8 @@ class PrinterPower:
             dev_type = cfg.get("type")
             if dev_type == "gpio":
                 dev = GpioDevice(cfg, self.chip_factory)
+            elif dev_type == "tplink_smartplug":
+                dev = TPLinkSmartPlug(cfg)
             else:
                 raise config.error(f"Unsupported Device Type: {dev_type}")
             self.devices[dev.get_name()] = dev
@@ -214,6 +220,115 @@ class GpioDevice:
     def close(self):
         self.line.release()
 
+
+#  This implementation based off the work tplink_smartplug
+#  script by Lubomir Stroetmann available at:
+#
+#  https://github.com/softScheck/tplink-smartplug
+#
+#  Copyright 2016 softScheck GmbH
+class TPLinkSmartPlug:
+    START_KEY = 0xAB
+    def __init__(self, config):
+        self.server = config.get_server()
+        self.addr = config.get("address")
+        self.port = config.getint("port", 9999)
+        name_parts = config.get_name().split(maxsplit=1)
+        if len(name_parts) != 2:
+            raise config.error(f"Invalid Section Name: {config.get_name()}")
+        self.name = name_parts[1]
+        self.state = "init"
+        IOLoop.current().spawn_callback(self.initialize)
+
+    async def _send_tplink_command(self, command):
+        out_cmd = {}
+        if command in ["on", "off"]:
+            out_cmd = {'system': {'set_relay_state':
+                       {'state': int(command == "on")}}}
+        elif command == "info":
+            out_cmd = {'system': {'get_sysinfo': {}}}
+        else:
+            raise self.server.error(f"Invalid tplink command: {command}")
+        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        stream = IOStream(s)
+        try:
+            await stream.connect((self.addr, self.port))
+            await stream.write(self._encrypt(out_cmd))
+            data = await stream.read_bytes(2048, partial=True)
+            length = struct.unpack(">I", data[:4])[0]
+            data = data[4:]
+            retries = 5
+            remaining = length - len(data)
+            while remaining and retries:
+                data += await stream.read_bytes(remaining)
+                remaining = length - len(data)
+                retries -= 1
+            if not retries:
+                raise self.server.error("Unable to read tplink packet")
+        except Exception:
+            msg = f"Error sending tplink command: {command}"
+            logging.exception(msg)
+            raise self.server.error(msg)
+        finally:
+            stream.close()
+        return json.loads(self._decrypt(data))
+
+    def _encrypt(self, data):
+        data = json.dumps(data)
+        key = self.START_KEY
+        res = struct.pack(">I", len(data))
+        for c in data:
+            val = key ^ ord(c)
+            key = val
+            res += bytes([val])
+        return res
+
+    def _decrypt(self, data):
+        key = self.START_KEY
+        res = ""
+        for c in data:
+            val = key ^ c
+            key = c
+            res += chr(val)
+        return res
+
+    async def initialize(self):
+        await self.refresh_status()
+
+    def get_name(self):
+        return self.name
+
+    def get_device_info(self):
+        return {
+            'device': self.name,
+            'status': self.state,
+            'type': "tplink_smartplug"
+        }
+
+    async def refresh_status(self):
+        try:
+            res = await self._send_tplink_command("info")
+            state = res['system']['get_sysinfo']['relay_state']
+        except Exception:
+            self.state = "error"
+            msg = f"Error Refeshing Device Status: {self.name}"
+            logging.exception(msg)
+            raise self.server.error(msg) from None
+        self.state = "on" if state else "off"
+
+    async def set_power(self, state):
+        try:
+            res = await self._send_tplink_command(state)
+            err = res['system']['set_relay_state']['err_code']
+        except Exception:
+            err = 1
+            logging.exception(f"Power Toggle Error: {self.name}")
+        if err:
+            self.state = "error"
+            raise self.server.error(
+                f"Error Toggling Device Power: {self.name}")
+        self.state = state
+
 # The power plugin has multiple configuration sections
 def load_plugin_multi(config):
     return PrinterPower(config)