Autodetecttelegram

CHANGELOG.rst

@@ -1,6 +1,9 @@
 Change Log
 ----------
 
+**1.5.0** (2024-08-25)
+- Allow the telegram specification to optionally be autodetected (`PR #87 <https://github.com/ndokter/dsmr_parser/pull/87>`_ by `clonerswords <https://github.com/clonerswords>`_)
+
 **1.4.2** (2024-07-14)
 
 - Bump Github Actions to latest versions in favor of Node deprecations (`PR #159 <https://github.com/ndokter/dsmr_parser/pull/159>`_ by `dennissiemensma <https://github.com/dennissiemensma>`_)
@@ -167,7 +170,7 @@ Remove deprecated asyncio coroutine decorator (`PR #76 <https://github.com/ndokt
 **0.12** (2018-09-23)
 
 - Add serial settings for DSMR v5.0 (`PR #31 <https://github.com/ndokter/dsmr_parser/pull/31>`_).
-- Lux-creos-obis-1.8.0 (`PR #32 <https://github.com/ndokter/dsmr_parser/pull/32>`_). 
+- Lux-creos-obis-1.8.0 (`PR #32 <https://github.com/ndokter/dsmr_parser/pull/32>`_).
 
 **0.11** (2017-09-18)
 

dsmr_parser/exceptions.py

@@ -4,3 +4,7 @@ class ParseError(Exception):
 
 class InvalidChecksumError(ParseError):
     pass
+
+
+class TelegramSpecificationMatchError(ParseError):
+    pass

dsmr_parser/parsers.py

@@ -9,7 +9,7 @@
 from dlms_cosem.protocol.xdlms import GeneralGlobalCipher
 
 from dsmr_parser.objects import MBusObject, MBusObjectPeak, CosemObject, ProfileGenericObject, Telegram
-from dsmr_parser.exceptions import ParseError, InvalidChecksumError
+from dsmr_parser.exceptions import ParseError, InvalidChecksumError, TelegramSpecificationMatchError
 from dsmr_parser.value_types import timestamp
 
 logger = logging.getLogger(__name__)
@@ -18,20 +18,17 @@
 class TelegramParser(object):
     crc16_tab = []
 
-    def __init__(self, telegram_specification, apply_checksum_validation=True):
+    def __init__(self, telegram_specification=None, apply_checksum_validation=True):
         """
-        :param telegram_specification: determines how the telegram is parsed
+        :param telegram_specification: determines how the telegram is parsed.
+            Will attempt to autodetect if omitted.
         :param apply_checksum_validation: validate checksum if applicable for
             telegram DSMR version (v4 and up).
         :type telegram_specification: dict
         """
         self.apply_checksum_validation = apply_checksum_validation
         self.telegram_specification = telegram_specification
-        # Regexes are compiled once to improve performance
-        self.telegram_specification_regexes = {
-            object["obis_reference"]: re.compile(object["obis_reference"], re.DOTALL | re.MULTILINE)
-            for object in self.telegram_specification['objects']
-        }
+        self._telegram_specification_regex = None
 
     def parse(self, telegram_data, encryption_key="", authentication_key="", throw_ex=False):  # noqa: C901
         """
@@ -46,6 +43,15 @@ def parse(self, telegram_data, encryption_key="", authentication_key="", throw_e
         :raises ParseError:
         :raises InvalidChecksumError:
         """
+        if not self.telegram_specification:
+            self.telegram_specification = \
+                match_telegram_specification(telegram_data)
+        if not self._telegram_specification_regex:
+            # Regexes are compiled once to improve performance
+            self._telegram_specification_regexes = {
+                object["obis_reference"]: re.compile(object["obis_reference"], re.DOTALL | re.MULTILINE)
+                for object in self.telegram_specification['objects']
+            }
 
         if "general_global_cipher" in self.telegram_specification:
             if self.telegram_specification["general_global_cipher"]:
@@ -85,7 +91,7 @@ def parse(self, telegram_data, encryption_key="", authentication_key="", throw_e
         telegram = Telegram()
 
         for object in self.telegram_specification['objects']:
-            pattern = self.telegram_specification_regexes[object["obis_reference"]]
+            pattern = self._telegram_specification_regexes[object["obis_reference"]]
             matches = pattern.findall(telegram_data)
 
             # Some signatures are optional and may not be present,
@@ -173,6 +179,37 @@ def crc16(telegram):
         return crcValue
 
 
+def match_telegram_specification(telegram_data):
+    """
+    Find telegram specification that matches the telegram data by trying all
+    specifications.
+
+    Could be further optimized to check the actual 0.2.8 OBIS reference which
+    is available for DSMR version 4 and up.
+
+    :param str telegram_data: full telegram from start ('/') to checksum
+            ('!ABCD') including line endings in between the telegram's lines
+    :return: telegram specification
+    :rtype: dict
+    """
+    # Prevent circular import
+    from dsmr_parser import telegram_specifications
+
+    for specification in telegram_specifications.ALL:
+        try:
+            TelegramParser(specification).parse(telegram_data)
+        except ParseError:
+            pass
+        else:
+            return specification
+
+    raise TelegramSpecificationMatchError(
+        'Could automatically match telegram specification. Make sure the data'
+        'is not corrupt. Alternatively manually specify one.'
+    )
+
+
+
 class DSMRObjectParser(object):
     """
     Parses an object (can also be see as a 'line') from a telegram.

dsmr_parser/telegram_specifications.py

@@ -486,8 +486,6 @@
     ]
 }
 
-ALL = (V2_2, V3, V4, V5)
-
 BELGIUM_FLUVIUS = {
     'checksum_support': True,
     'objects': [
@@ -1368,3 +1366,17 @@
         }
     ]
 }
+
+ALL = (
+    V2_2,
+    V3,
+    V4,
+    V5,
+    BELGIUM_FLUVIUS,
+    LUXEMBOURG_SMARTY,
+    SWEDEN,
+    SAGEMCOM_T210_D_R,
+    AUSTRIA_ENERGIENETZE_STEIERMARK,
+    ISKRA_IE,
+    EON_HUNGARY
+)

setup.py

@@ -7,7 +7,7 @@
     author_email='[email protected]',
     license='MIT',
     url='https://github.com/ndokter/dsmr_parser',
-    version='1.4.2',
+    version='1.5.0',
     packages=find_packages(exclude=('test', 'test.*')),
     install_requires=[
         'pyserial>=3,<4',

test/test_match_telegram_specification.py

@@ -0,0 +1,29 @@
+import unittest
+
+from dsmr_parser.exceptions import TelegramSpecificationMatchError
+from dsmr_parser.parsers import match_telegram_specification
+from dsmr_parser import telegram_specifications
+from test import example_telegrams
+
+
+class MatchTelegramSpecificationTest(unittest.TestCase):
+
+    def test_v2_2(self):
+        assert match_telegram_specification(example_telegrams.TELEGRAM_V2_2) \
+           == telegram_specifications.V2_2
+
+    def test_v3(self):
+        assert match_telegram_specification(example_telegrams.TELEGRAM_V3) \
+           == telegram_specifications.V3
+
+    def test_v4_2(self):
+        assert match_telegram_specification(example_telegrams.TELEGRAM_V4_2) \
+           == telegram_specifications.V4
+
+    def test_v5(self):
+        assert match_telegram_specification(example_telegrams.TELEGRAM_V5) \
+           == telegram_specifications.V5
+
+    def test_malformed_telegram(self):
+        with self.assertRaises(TelegramSpecificationMatchError):
+            match_telegram_specification(example_telegrams.TELEGRAM_V5[:-4])

test/test_parse_v2_2.py

@@ -12,6 +12,15 @@
 class TelegramParserV2_2Test(unittest.TestCase):
     """ Test parsing of a DSMR v2.2 telegram. """
 
+    def test_telegram_specification_matching(self):
+        parser = TelegramParser()
+        parser.parse(TELEGRAM_V2_2)
+
+        self.assertEqual(
+            parser.telegram_specification,
+            telegram_specifications.V2_2
+        )
+
     def test_parse(self):
         parser = TelegramParser(telegram_specifications.V2_2)
         try:

test/test_parse_v3.py

@@ -12,6 +12,15 @@
 class TelegramParserV3Test(unittest.TestCase):
     """ Test parsing of a DSMR v3 telegram. """
 
+    def test_telegram_specification_matching(self):
+        parser = TelegramParser()
+        parser.parse(TELEGRAM_V3)
+
+        self.assertEqual(
+            parser.telegram_specification,
+            telegram_specifications.V3
+        )
+
     def test_parse(self):
         parser = TelegramParser(telegram_specifications.V3)
         try:

test/test_parse_v4_2.py

@@ -15,6 +15,15 @@
 class TelegramParserV4_2Test(unittest.TestCase):
     """ Test parsing of a DSMR v4.2 telegram. """
 
+    def test_telegram_specification_matching(self):
+        parser = TelegramParser()
+        parser.parse(TELEGRAM_V4_2)
+
+        self.assertEqual(
+            parser.telegram_specification,
+            telegram_specifications.V4
+        )
+
     def test_parse(self):
         parser = TelegramParser(telegram_specifications.V4)
         try:

test/test_parse_v5.py

@@ -15,6 +15,15 @@
 class TelegramParserV5Test(unittest.TestCase):
     """ Test parsing of a DSMR v5.x telegram. """
 
+    def test_telegram_specification_matching(self):
+        parser = TelegramParser()
+        parser.parse(TELEGRAM_V5)
+
+        self.assertEqual(
+            parser.telegram_specification,
+            telegram_specifications.V5
+        )
+
     def test_parse(self):
         parser = TelegramParser(telegram_specifications.V5)
         try: