S allius/issue117 (#118)

* add shutdown flag

* add more register definitions

* add start commando for client side connections

* add first support for port 8899

* fix shutdown

* add client_mode configuration

* read client_mode config to setup inverter connections

* add client_mode connections over port 8899

* add preview build

app/src/modbus_tcp.py

@@ -0,0 +1,70 @@
+import logging
+import traceback
+import asyncio
+from config import Config
+
+# import gc
+from gen3plus.inverter_g3p import InverterG3P
+
+logger = logging.getLogger('conn')
+
+
+class ModbusConn():
+    def __init__(self, host, port):
+        self.host = host
+        self.port = port
+        self.addr = (host, port)
+        self.stream = None
+
+    async def __aenter__(self) -> 'InverterG3P':
+        '''Establish a client connection to the TSUN cloud'''
+        connection = asyncio.open_connection(self.host, self.port)
+        reader, writer = await connection
+        self.stream = InverterG3P(reader, writer, self.addr)
+        logging.info(f'[{self.stream.node_id}:{self.stream.conn_no}] '
+                     f'Connected to {self.addr}')
+        self.stream.inc_counter('Inverter_Cnt')
+        return self.stream
+
+    async def __aexit__(self, exc_type, exc, tb):
+        self.stream.dec_counter('Inverter_Cnt')
+
+
+class ModbusTcp():
+
+    def __init__(self, loop) -> None:
+        inverters = Config.get('inverters')
+        # logging.info(f'Inverters: {inverters}')
+
+        for inv in inverters.values():
+            if (type(inv) is dict
+               and 'monitor_sn' in inv
+               and 'client_mode' in inv):
+                client = inv['client_mode']
+                # logging.info(f"SerialNo:{inv['monitor_sn']} host:{client['host']} port:{client['port']}")  # noqa: E501
+                loop.create_task(self.modbus_loop(client['host'],
+                                                  client['port'],
+                                                  inv['monitor_sn']))
+
+    async def modbus_loop(self, host, port, snr: int) -> None:
+        '''Loop for receiving messages from the TSUN cloud (client-side)'''
+        while True:
+            try:
+                async with ModbusConn(host, port) as stream:
+                    await stream.send_start_cmd(snr)
+                    await stream.loop()
+                    logger.info(f'[{stream.node_id}:{stream.conn_no}] '
+                                f'Connection closed - Shutdown: '
+                                f'{stream.shutdown_started}')
+                    if stream.shutdown_started:
+                        return
+
+            except (ConnectionRefusedError, TimeoutError) as error:
+                logging.info(f'{error}')
+
+            except Exception:
+                logging.error(
+                    f"ModbusTcpCreate: Exception for {(host,port)}:\n"
+                    f"{traceback.format_exc()}")
+
+            await asyncio.sleep(10)