Merge branch 'btledev_private' of sqozz/sem6000 into master

This cleans up some rough edges of the initial version.

1. Reconnect support introduces better handling of missing or misbehaving wall sockets.
2. Variable visibility for the internally used ble characteristics just give the reader a slight clue about their (un)importance for them.
3. Variable access was cleaned up to use the provided setter for cmd and payload.
4. Some spaghetti code got slightly more readable.
5. Finally, graceful handling of disconnects is now possible. This allows short lived scripts (e.g. home-assistant components) to access multiple sockets with the same BLE adapter.

example.py

@@ -1,16 +1,23 @@
-from sem6000 import SEMSocket
 import time
-socket = SEMSocket('f0:c7:7f:0d:e7:17')
+from sem6000 import SEMSocket
 
-socket.login("1337")
+# auto_reconnect_timeout enabled auto reconnect if sending a command fails. Valid values:
-socket.changePassword("1234")
+# None (default): everything that fails throws NotConnectedException's
-socket.login("1234")
+# -1: infinite retries
-#socket.changePassword("1337")
+# integer: seconds before exception is thrown
+
+socket = SEMSocket('f0:c7:7f:0d:e7:17', auto_reconnect_timeout=None)
+
+#socket.login("1337")
+#socket.changePassword("1234")
+#socket.login("1234")
 
 while True:
-    break;
     time.sleep(1)
+    try:
         socket.getStatus()
         socket.setStatus(True)
         print("=== {} ({}) ===".format(socket.mac_address, "on" if socket.powered else "off"))
         print("\t{}V {}A → {}W@{}Hz".format(socket.voltage, socket.current, socket.power, socket.frequency))
+    except SEMSocket.NotConnectedException:
+        socket.reconnect(-1) #infinite reconnect attempts

sem6000.py

@@ -1,11 +1,10 @@
 from bluepy import btle
-import struct
 import time
-import pdb
 import uuid
 
 class SEMSocket():
     password = "0000"
+    auto_reconnect_timeout = None
     powered = False
     voltage = 0
     current = 0
@@ -13,104 +12,21 @@ class SEMSocket():
     frequency = 0
     mac_address = ""
     custom_service = None
-    read_char = None
+    _read_char = None
-    write_char = None
+    _write_char = None
-    notify_char = None
+    _notify_char = None
+    _btle_device = None
 
-    def __init__(self, mac):
+    def __init__(self, mac, auto_reconnect_timeout = None):
         self.mac_address = mac
-        self.btle_device = btle.Peripheral(self.mac_address,addrType=btle.ADDR_TYPE_PUBLIC,iface=0)
+        self.auto_reconnect_timeout = auto_reconnect_timeout
-        self.btle_handler = self.BTLEHandler(self)
+        try:
-
+            self.reconnect()
-        self.custom_service = self.btle_device.getServiceByUUID(0xfff0)
+        except self.NotConnectedException:
-        self.read_char      = self.custom_service.getCharacteristics("0000fff1-0000-1000-8000-00805f9b34fb")[0]
+            # initial connection may fail. It is up to the code what to do
-        print(self.read_char.read())
+            pass
-        self.write_char     = self.custom_service.getCharacteristics("0000fff3-0000-1000-8000-00805f9b34fb")[0]
-        self.notify_char    = self.custom_service.getCharacteristics("0000fff4-0000-1000-8000-00805f9b34fb")[0]
-        self.btle_device.setDelegate(self.btle_handler)
-
-    class BTLEMessage():
-        MAGIC_START = bytearray([0x0f])
-        MAGIC_END = bytearray([0xff, 0xff])
-        __data = bytearray()
-        __cmd = bytearray(1) # cmd cannot be empty
-        __payload = bytearray()
-
-        def __init__(self, btle_device, cmd=bytearray(), payload=bytearray()):
-            self.__btle_device = btle_device
-            self.cmd = cmd
-            self.payload = payload
-
-        @property
-        def cmd(self):
-            return self.__cmd
-
-        @cmd.setter
-        def cmd(self, cmd):
-            self.__data = self.MAGIC_START + bytearray(1) + cmd + self.payload + bytearray(1) + self.MAGIC_END
-            self.__cmd = cmd
-            self.__calc_length()
-            self.__calc_checksum()
-
-        @property
-        def payload(self):
-            return self.__payload
-
-        @payload.setter
-        def payload(self, payload):
-            self.__data = self.MAGIC_START + bytearray(1) + self.cmd + payload + bytearray(1) + self.MAGIC_END
-            self.__payload = payload
-            self.__calc_length()
-            self.__calc_checksum()
-
-        def __calc_checksum(self):
-            checksum = 1
-            for i in range(2, self.__data[1] + 2):
-                checksum += self.__data[i]
-            self.__data[-3] = checksum & 0xff
-
-        def __calc_length(self):
-            self.__data[1] = 1 + len(self.__payload) + 1 # cmd + payload + checksum
-
-        def send(self):
-            self.__btle_device.write_char.write(self.__data, True)
-            self.__btle_device.btle_device.waitForNotifications(5)
-
-
-    class BTLEHandler(btle.DefaultDelegate):
-        def __init__(self, btle_device):
-            btle.DefaultDelegate.__init__(self)
-            self.btle_device = btle_device
-
-        def handleNotification(self, cHandle, data):
-            message_type = data[2]
-            if message_type == 0x00:
-                if data[4] == 0x01:
-                    print("Checksum error!")
-                else:
-                    print("Unknown error:", data)
-            elif message_type == 0x03: #switch toggle
-                print("Switch toggled")
-                self.btle_device.getStatus()
-            elif message_type == 0x04: #status related data
-                self.btle_device.voltage = data[8]
-                self.btle_device.current = (data[9] << 8 | data[10]) / 1000
-                self.btle_device.power = (data[5] << 16 | data[6] << 8 | data[7]) / 1000
-                self.btle_device.frequency = data[11]
-                self.btle_device.powered = bool(data[4])
-            elif message_type == 0x17:
-                if data[5] == 0x00 or data[5] == 0x01:
-                    if not data[4]:
-                        print("Login successful")
-                    else:
-                        print("Login failed")
-                else:
-                    print("5th byte of login-response is > 1:", data)
-            else:
-                print ("Unknown message from Handle: 0x" + format(cHandle,'02X') + " Value: "+ format(data))
 
     def getStatus(self):
-        print("GetStatus")
         #15, 5, 4, 0, 0, 0, 5, -1, -1
         cmd = bytearray([0x04])
         payload = bytearray([0x00, 0x00, 0x00])
@@ -118,7 +34,6 @@ class SEMSocket():
         msg.send()
 
     def setStatus(self, status):
-        print("SetStatus:", status)
         # 0f 06 03 00 01 00 00 05 ff ff  -> on
         # 0f 06 03 00 00 00 00 04 ff ff  -> off
         cmd = bytearray([0x03])
@@ -127,16 +42,13 @@ class SEMSocket():
         msg.send()
 
     def login(self, password):
-        print("Login")
         self.password = password
         cmd = bytearray([0x17])
         payload = bytearray()
         payload.append(0x00)
         payload.append(0x00)
-        payload.append(int(self.password[0]))
+        for i in range(4):
-        payload.append(int(self.password[1]))
+            payload.append(int(self.password[i]))
-        payload.append(int(self.password[2]))
-        payload.append(int(self.password[3]))
         payload.append(0x00)
         payload.append(0x00)
         payload.append(0x00)
@@ -145,23 +57,61 @@ class SEMSocket():
         msg.send()
 
     def changePassword(self, newPassword):
-        print("Change Password")
         cmd = bytearray([0x17])
         payload = bytearray()
         payload.append(0x00)
         payload.append(0x01)
-        payload.append(int(newPassword[0]))
+        for i in range(4):
-        payload.append(int(newPassword[1]))
+            payload.append(int(self.newPassword[i]))
-        payload.append(int(newPassword[2]))
+        for i in range(4):
-        payload.append(int(newPassword[3]))
+            payload.append(int(self.password[i]))
-        payload.append(int(self.password[0]))
-        payload.append(int(self.password[1]))
-        payload.append(int(self.password[2]))
-        payload.append(int(self.password[3]))
         self.password = newPassword
         msg = self.BTLEMessage(self, cmd, payload)
         msg.send()
 
+    @property
+    def connected(self):
+        try:
+            if "conn" in self._btle_device.status().get("state"):
+                return True
+            else:
+                return False
+        except:
+            return False
+
+    def __reconnect(self):
+        self.disconnect()
+        self.connect()
+
+    def reconnect(self, timeout = None):
+        if timeout == None:
+            self.__reconnect()
+        else:
+            reconnect_start = time.time()
+            while abs(reconnect_start - time.time()) < timeout or timeout == -1:
+                self.__reconnect()
+
+        if not self.connected:
+            raise self.NotConnectedException
+
+    def connect(self):
+        self.disconnect()
+        if not self._btle_device:
+            self._btle_device = btle.Peripheral(self.mac_address,addrType=btle.ADDR_TYPE_PUBLIC,iface=0)
+        else:
+            self._btle_device.connect(self.mac_address)
+        self._btle_handler = self.BTLEHandler(self)
+
+        self._custom_service = self._btle_device.getServiceByUUID(0xfff0)
+        self._read_char      = self._custom_service.getCharacteristics("0000fff1-0000-1000-8000-00805f9b34fb")[0]
+        self._write_char     = self._custom_service.getCharacteristics("0000fff3-0000-1000-8000-00805f9b34fb")[0]
+        self._notify_char    = self._custom_service.getCharacteristics("0000fff4-0000-1000-8000-00805f9b34fb")[0]
+        self._btle_device.setDelegate(self._btle_handler)
+
+    def disconnect(self):
+        if self.connected == True:
+            self._btle_device.disconnect()
+
     #def SynVer(self):
     #    print("SynVer")
     #    self.read_char.read_value()
@@ -186,4 +136,86 @@ class SEMSocket():
     #    self.GetSynConfig()
     #    #self.GetSN()
 
+    class NotConnectedException(Exception):
+        pass
 
+    class BTLEMessage():
+        MAGIC_START = bytearray([0x0f])
+        MAGIC_END = bytearray([0xff, 0xff])
+        __data = bytearray()
+        __cmd = bytearray(1) # cmd cannot be empty
+        __payload = bytearray()
+
+        def __init__(self, btle_device, cmd=bytearray(), payload=bytearray()):
+            self.__btle_device = btle_device
+            self.cmd = cmd
+            self.payload = payload
+
+        @property
+        def cmd(self):
+            return self.__cmd
+
+        @cmd.setter
+        def cmd(self, cmd):
+            self.__data = self.MAGIC_START + bytearray(1) + cmd + self.__payload + bytearray(1) + self.MAGIC_END
+            self.__cmd = cmd
+            self.__calc_length()
+            self.__calc_checksum()
+
+        @property
+        def payload(self):
+            return self.__payload
+
+        @payload.setter
+        def payload(self, payload):
+            self.__data = self.MAGIC_START + bytearray(1) + self.__cmd + payload + bytearray(1) + self.MAGIC_END
+            self.__payload = payload
+            self.__calc_length()
+            self.__calc_checksum()
+
+        def __calc_checksum(self):
+            checksum = 1
+            for i in range(2, self.__data[1] + 2):
+                checksum += self.__data[i]
+            self.__data[-3] = checksum & 0xff
+
+        def __calc_length(self):
+            self.__data[1] = 1 + len(self.__payload) + 1 # cmd + payload + checksum
+
+        def send(self):
+            if not self.__btle_device.connected:
+                self.__btle_device.reconnect(self.__btle_device.auto_reconnect_timeout)
+
+            self.__btle_device._write_char.write(self.__data, True)
+            self.__btle_device._btle_device.waitForNotifications(5)
+
+
+    class BTLEHandler(btle.DefaultDelegate):
+        def __init__(self, btle_device):
+            btle.DefaultDelegate.__init__(self)
+            self.__btle_device = btle_device
+
+        def handleNotification(self, cHandle, data):
+            message_type = data[2]
+            if message_type == 0x00:
+                if data[4] == 0x01:
+                    print("Checksum error!")
+                else:
+                    print("Unknown error:", data)
+            elif message_type == 0x03: #switch toggle
+                print("Switch toggled")
+                self.__btle_device.getStatus()
+            elif message_type == 0x04: #status related data
+                self.__btle_device.voltage = data[8]
+                self.__btle_device.current = (data[9] << 8 | data[10]) / 1000
+                self.__btle_device.power = (data[5] << 16 | data[6] << 8 | data[7]) / 1000
+                self.__btle_device.frequency = data[11]
+                self.__btle_device.powered = bool(data[4])
+            elif message_type == 0x17:
+                if data[5] == 0x00 or data[5] == 0x01:
+                    if data[4]:
+                        print("Login failed")
+                else:
+                    print("5th byte of login-response is > 1:", data)
+            else:
+                print ("Unknown message from Handle: 0x" + format(cHandle,'02X') + " Value: "+ format(data))