Fix modbus sync/async issues (#34043)

* add pyserial to manifest

pymodbus is very developer oriented and assumes every developer
adapt the requierements.txt to his/hers needs.

Our requirements.txt is different it contains all posibilities allowing
user to later change configuration without having to install extra
packages.

As a consequence manifest.json needs to include the pyserial.

* modbus: make truly async client creation

Make hass call listen_once async.
Integrate content of start_modbus into async_setup.

Do not use the boiler plate create tcp client function from
pymodbus as it is sync, and also does not work well with asyncio,
instead call the init_<type> directly, since that is async.

* both component/modbus and component/serial uses pyserial-async
but with slighty different version requirements.

Combined the 2.

* Review 1

* Review 2

* Review

@staticmethod is no good, because the function uses class variables.

* Review

Pytest is sometimes a bit cryptic, lets hope this does it.

homeassistant/components/modbus/__init__.py

@@ -3,13 +3,21 @@ import asyncio
 import logging
 
 from async_timeout import timeout
-from pymodbus.client.asynchronous import schedulers
+from pymodbus.client.asynchronous.asyncio import (
-from pymodbus.client.asynchronous.serial import AsyncModbusSerialClient as ClientSerial
+    AsyncioModbusSerialClient,
-from pymodbus.client.asynchronous.tcp import AsyncModbusTCPClient as ClientTCP
+    ModbusClientProtocol,
-from pymodbus.client.asynchronous.udp import AsyncModbusUDPClient as ClientUDP
+    init_tcp_client,
+    init_udp_client,
+)
 from pymodbus.exceptions import ModbusException
+from pymodbus.factory import ClientDecoder
 from pymodbus.pdu import ExceptionResponse
-from pymodbus.transaction import ModbusRtuFramer
+from pymodbus.transaction import (
+    ModbusAsciiFramer,
+    ModbusBinaryFramer,
+    ModbusRtuFramer,
+    ModbusSocketFramer,
+)
 import voluptuous as vol
 
 from homeassistant.const import (
@@ -105,13 +113,6 @@ async def async_setup(hass, config):
         for client in hub_collect.values():
             del client
 
-    def start_modbus():
-        """Start Modbus service."""
-        for client in hub_collect.values():
-            client.setup()
-
-        hass.bus.listen_once(EVENT_HOMEASSISTANT_STOP, stop_modbus)
-
     async def write_register(service):
         """Write Modbus registers."""
         unit = int(float(service.data[ATTR_UNIT]))
@@ -136,7 +137,11 @@ async def async_setup(hass, config):
         await hub_collect[client_name].write_coil(unit, address, state)
 
     # do not wait for EVENT_HOMEASSISTANT_START, activate pymodbus now
-    await hass.async_add_executor_job(start_modbus)
+    for client in hub_collect.values():
+        await client.setup(hass)
+
+    # register function to gracefully stop modbus
+    hass.bus.async_listen_once(EVENT_HOMEASSISTANT_STOP, stop_modbus)
 
     # Register services for modbus
     hass.services.async_register(
@@ -189,47 +194,55 @@ class ModbusHub:
             await asyncio.sleep(self._config_delay)
             self._config_delay = 0
 
-    def setup(self):
+    @staticmethod
-        """Set up pymodbus client."""
+    def _framer(method):
-        # pylint: disable = E0633
+        if method == "ascii":
-        # Client* do deliver loop, client as result but
+            framer = ModbusAsciiFramer(ClientDecoder())
-        # pylint does not accept that fact
+        elif method == "rtu":
+            framer = ModbusRtuFramer(ClientDecoder())
+        elif method == "binary":
+            framer = ModbusBinaryFramer(ClientDecoder())
+        elif method == "socket":
+            framer = ModbusSocketFramer(ClientDecoder())
+        else:
+            framer = None
+        return framer
 
+    async def setup(self, hass):
+        """Set up pymodbus client."""
         if self._config_type == "serial":
-            _, self._client = ClientSerial(
+            # reconnect ??
-                schedulers.ASYNC_IO,
+            framer = self._framer(self._config_method)
-                method=self._config_method,
+
-                port=self._config_port,
+            # just a class creation no IO or other slow items
+            self._client = AsyncioModbusSerialClient(
+                self._config_port,
+                protocol_class=ModbusClientProtocol,
+                framer=framer,
+                loop=self._loop,
                 baudrate=self._config_baudrate,
-                stopbits=self._config_stopbits,
                 bytesize=self._config_bytesize,
                 parity=self._config_parity,
-                loop=self._loop,
+                stopbits=self._config_stopbits,
             )
+            await self._client.connect()
         elif self._config_type == "rtuovertcp":
-            _, self._client = ClientTCP(
+            # framer ModbusRtuFramer ??
-                schedulers.ASYNC_IO,
+            # timeout ??
-                host=self._config_host,
+            self._client = await init_tcp_client(
-                port=self._config_port,
+                None, self._loop, self._config_host, self._config_port
-                framer=ModbusRtuFramer,
-                timeout=self._config_timeout,
-                loop=self._loop,
             )
         elif self._config_type == "tcp":
-            _, self._client = ClientTCP(
+            # framer ??
-                schedulers.ASYNC_IO,
+            # timeout ??
-                host=self._config_host,
+            self._client = await init_tcp_client(
-                port=self._config_port,
+                None, self._loop, self._config_host, self._config_port
-                timeout=self._config_timeout,
-                loop=self._loop,
             )
         elif self._config_type == "udp":
-            _, self._client = ClientUDP(
+            # framer ??
-                schedulers.ASYNC_IO,
+            # timeout ??
-                host=self._config_host,
+            self._client = await init_udp_client(
-                port=self._config_port,
+                None, self._loop, self._config_host, self._config_port
-                timeout=self._config_timeout,
-                loop=self._loop,
             )
         else:
             assert False

homeassistant/components/modbus/manifest.json

@@ -2,6 +2,7 @@
   "domain": "modbus",
   "name": "Modbus",
   "documentation": "https://www.home-assistant.io/integrations/modbus",
-  "requirements": ["pymodbus==2.3.0"],
+  "requirements": ["pymodbus==2.3.0",
+                   "pyserial-asyncio==0.4"],
   "codeowners": ["@adamchengtkc", "@janiversen"]
 }

requirements_all.txt

@@ -1528,6 +1528,7 @@ pysdcp==1
 # homeassistant.components.sensibo
 pysensibo==1.0.3
 
+# homeassistant.components.modbus
 # homeassistant.components.serial
 pyserial-asyncio==0.4
 

requirements_test_all.txt

@@ -597,6 +597,10 @@ pyps4-2ndscreen==1.0.7
 # homeassistant.components.qwikswitch
 pyqwikswitch==0.93
 
+# homeassistant.components.modbus
+# homeassistant.components.serial
+pyserial-asyncio==0.4
+
 # homeassistant.components.signal_messenger
 pysignalclirestapi==0.2.4