added telegram CRC verification

dsmr_parser/serial.py

@@ -1,11 +1,11 @@
 import asyncio
 import logging
-
 import serial
-
 import serial_asyncio
+
 from dsmr_parser.exceptions import ParseError
-from dsmr_parser.parsers import TelegramParser, TelegramParserV2_2
+from dsmr_parser.parsers import TelegramParser, TelegramParserV2_2, \
+    TelegramParserV4
 
 logger = logging.getLogger(__name__)
 
@@ -32,15 +32,20 @@ SERIAL_SETTINGS_V4 = {
 
 
 def is_start_of_telegram(line):
+    """
+    :type line: line
+    """
     return line.startswith('/')
 
 
 def is_end_of_telegram(line):
+    """
+    :type line: line
+    """
     return line.startswith('!')
 
 
 class SerialReader(object):
-
     PORT_KEY = 'port'
 
     def __init__(self, device, serial_settings, telegram_specification):
@@ -49,8 +54,11 @@ class SerialReader(object):
 
         if serial_settings is SERIAL_SETTINGS_V2_2:
             telegram_parser = TelegramParserV2_2
+        elif serial_settings is SERIAL_SETTINGS_V4:
+            telegram_parser = TelegramParserV4
         else:
             telegram_parser = TelegramParser
+
         self.telegram_parser = telegram_parser(telegram_specification)
 
     def read(self):
@@ -65,7 +73,7 @@ class SerialReader(object):
 
             while True:
                 line = serial_handle.readline()
-                line = line.decode('ascii')
+                line = line.decode('ascii')  # TODO move this to the parser?
 
                 # Telegrams need to be complete because the values belong to a
                 # particular reading and can also be related to eachother.
@@ -75,7 +83,12 @@ class SerialReader(object):
                 telegram.append(line)
 
                 if is_end_of_telegram(line):
-                    yield self.telegram_parser.parse(telegram)
+
+                    try:
+                        yield self.telegram_parser.parse(telegram)
+                    except ParseError as e:
+                        logger.error('Failed to parse telegram: %s', e)
+
                     telegram = []
 
 
@@ -119,7 +132,7 @@ class AsyncSerialReader(SerialReader):
                     parsed_telegram = self.telegram_parser.parse(telegram)
                     # push new parsed telegram onto queue
                     queue.put_nowait(parsed_telegram)
-                except ParseError:
-                    logger.exception("failed to parse telegram")
+                except ParseError as e:
+                    logger.warning('Failed to parse telegram: %s', e)
 
                 telegram = []