S allius/issue205 (#207)

* Add SolarmanEmu class

* Forward a device ind to establish the EMU connection

* Move SolarmanEmu class into a dedicated file

* Add cloud connection counter

* Send inverter data in emulator mode

* Improve emulator mode

- parse more values from MQTT register
- differ between inverter and logger serial no

* Add some unit tests for SolarmanEmu class

* Send seconds since last sync in data packets

* Increase test coverage

app/src/gen3plus/solarman_emu.py

@@ -0,0 +1,144 @@
+import logging
+import struct
+
+if __name__ == "app.src.gen3plus.solarman_emu":
+    from app.src.async_ifc import AsyncIfc
+    from app.src.gen3plus.solarman_v5 import SolarmanBase
+    from app.src.my_timer import Timer
+    from app.src.infos import Register
+else:  # pragma: no cover
+    from async_ifc import AsyncIfc
+    from gen3plus.solarman_v5 import SolarmanBase
+    from my_timer import Timer
+    from infos import Register
+
+logger = logging.getLogger('msg')
+
+
+class SolarmanEmu(SolarmanBase):
+    def __init__(self, addr, ifc: "AsyncIfc",
+                 server_side: bool, client_mode: bool):
+        super().__init__(addr, ifc, server_side=False,
+                         _send_modbus_cb=None,
+                         mb_timeout=8)
+        logging.debug('SolarmanEmu.init()')
+        self.db = ifc.remote.stream.db
+        self.snr = ifc.remote.stream.snr
+        self.hb_timeout = 60
+        '''actual heatbeat timeout from the last response message'''
+        self.data_up_inv = self.db.get_db_value(Register.DATA_UP_INTERVAL)
+        '''time interval for getting new MQTT data messages'''
+        self.hb_timer = Timer(self.send_heartbeat_cb, self.node_id)
+        self.data_timer = Timer(self.send_data_cb, self.node_id)
+        self.last_sync = self._emu_timestamp()
+        '''timestamp when we send the last sync message (4110)'''
+        self.pkt_cnt = 0
+        '''last sent packet number'''
+
+        self.switch = {
+
+            0x4210: 'msg_data_ind',      # real time data
+            0x1210: self.msg_response,   # at least every 5 minutes
+
+            0x4710: 'msg_hbeat_ind',     # heatbeat
+            0x1710: self.msg_response,   # every 2 minutes
+
+            0x4110: 'msg_dev_ind',        # device data, sync start
+            0x1110: self.msg_response,    # every 3 hours
+
+        }
+
+        self.log_lvl = {
+
+            0x4110: logging.INFO,   # device data, sync start
+            0x1110: logging.INFO,   # every 3 hours
+
+            0x4210: logging.INFO,   # real time data
+            0x1210: logging.INFO,   # at least every 5 minutes
+
+            0x4710: logging.DEBUG,  # heatbeat
+            0x1710: logging.DEBUG,  # every 2 minutes
+
+        }
+
+    '''
+    Our puplic methods
+    '''
+    def close(self) -> None:
+        logging.info('SolarmanEmu.close()')
+        # we have references to methods of this class in self.switch
+        # so we have to erase self.switch, otherwise this instance can't be
+        # deallocated by the garbage collector ==> we get a memory leak
+        self.switch.clear()
+        self.log_lvl.clear()
+        self.hb_timer.close()
+        self.data_timer.close()
+        self.db = None
+        super().close()
+
+    def _set_serial_no(self, snr: int):
+        logging.debug(f'SolarmanEmu._set_serial_no, snr: {snr}')
+        self.unique_id = str(snr)
+
+    def _init_new_client_conn(self) -> bool:
+        logging.debug('SolarmanEmu.init_new()')
+        self.data_timer.start(self.data_up_inv)
+        return False
+
+    def next_pkt_cnt(self):
+        '''get the next packet number'''
+        self.pkt_cnt = (self.pkt_cnt + 1) & 0xffffffff
+        return self.pkt_cnt
+
+    def seconds_since_last_sync(self):
+        '''get seconds since last 0x4110 message was sent'''
+        return self._emu_timestamp() - self.last_sync
+
+    def send_heartbeat_cb(self, exp_cnt):
+        '''send a heartbeat to the TSUN cloud'''
+        self._build_header(0x4710)
+        self.ifc.tx_add(struct.pack('<B', 0))
+        self._finish_send_msg()
+        log_lvl = self.log_lvl.get(0x4710, logging.WARNING)
+        self.ifc.tx_log(log_lvl, 'Send heartbeat:')
+        self.ifc.tx_flush()
+
+    def send_data_cb(self, exp_cnt):
+        '''send a inverter data message to the TSUN cloud'''
+        self.hb_timer.start(self.hb_timeout)
+        self.data_timer.start(self.data_up_inv)
+        _len = 420
+        ftype = 1
+        build_msg = self.db.build(_len, 0x42, ftype)
+
+        self._build_header(0x4210)
+        self.ifc.tx_add(
+            struct.pack(
+                '<BHLLLHL', ftype, 0x02b0,
+                self._emu_timestamp(),
+                self.seconds_since_last_sync(),
+                self.time_ofs,
+                1,  # offset 0x1a
+                self.next_pkt_cnt()))
+        self.ifc.tx_add(build_msg[0x20:])
+        self._finish_send_msg()
+        log_lvl = self.log_lvl.get(0x4210, logging.WARNING)
+        self.ifc.tx_log(log_lvl, 'Send inv-data:')
+        self.ifc.tx_flush()
+
+    '''
+    Message handler methods
+    '''
+    def msg_response(self):
+        '''handle a received response from the TSUN cloud'''
+        logger.debug("EMU received rsp:")
+        _, _, ts, hb = super().msg_response()
+        logger.debug(f"EMU ts:{ts} hb:{hb}")
+        self.hb_timeout = hb
+        self.time_ofs = ts - self._emu_timestamp()
+        self.hb_timer.start(self.hb_timeout)
+
+    def msg_unknown(self):
+        '''counts a unknown or unexpected message from the TSUN cloud'''
+        logger.warning(f"EMU Unknow Msg: ID:{int(self.control):#04x}")
+        self.inc_counter('Unknown_Msg')