Merge pull request #67 from M0r13n/type-27-messages-should-be-signed

Makes type 27 messages lat and lon signed

CHANGELOG.txt

@@ -1,6 +1,14 @@
 ====================
  pyais CHANGELOG
 ====================
+-------------------------------------------------------------------------------
+ Version 2.1.1 24 Apr 2022
+-------------------------------------------------------------------------------
+* Closes https://github.com/M0r13n/pyais/issues/65
+  * makes lat and lon signed for type 27 messages
+* drops nosetest as a development dependency
+
+
 -------------------------------------------------------------------------------
  Version 2.1.0 14 Apr 2022
 -------------------------------------------------------------------------------

pyais/__init__.py

@@ -4,7 +4,7 @@
 from pyais.decode import decode
 
 __license__ = 'MIT'
-__version__ = '2.1.0'
+__version__ = '2.1.1'
 __author__ = 'Leon Morten Richter'
 
 __all__ = (

pyais/messages.py

@@ -1359,8 +1359,8 @@ class MessageType27(Payload):
     accuracy = bit_field(1, bool, default=0, signed=False)
     raim = bit_field(1, bool, default=0, signed=False)
     status = bit_field(4, int, default=0, from_converter=NavigationStatus, to_converter=NavigationStatus, signed=False)
-    lon = bit_field(18, float, from_converter=from_lat_lon_600, to_converter=to_lat_lon_600, default=0)
-    lat = bit_field(17, float, from_converter=from_lat_lon_600, to_converter=to_lat_lon_600, default=0)
+    lon = bit_field(18, float, from_converter=from_lat_lon_600, to_converter=to_lat_lon_600, default=0, signed=True)
+    lat = bit_field(17, float, from_converter=from_lat_lon_600, to_converter=to_lat_lon_600, default=0, signed=True)
     speed = bit_field(6, float, default=0, signed=False)
     course = bit_field(9, float, default=0, signed=False)
     gnss = bit_field(1, bool, default=0, signed=False)

tests/test_decode.py

@@ -8,15 +8,25 @@
 
 from pyais import NMEAMessage, encode_dict
 from pyais.ais_types import AISType
-from pyais.constants import ManeuverIndicator, NavigationStatus, ShipType, NavAid, EpfdType, StationType, TransmitMode
+from pyais.constants import (EpfdType, ManeuverIndicator, NavAid,
+                             NavigationStatus, ShipType, StationType,
+                             TransmitMode)
 from pyais.decode import decode
 from pyais.exceptions import UnknownMessageException
-from pyais.messages import MessageType18, MessageType5, MessageType6, MSG_CLASS, MessageType24PartA, MessageType24PartB, \
-    MessageType25AddressedStructured, MessageType25BroadcastStructured, MessageType25AddressedUnstructured, \
-    MessageType25BroadcastUnstructured, MessageType26AddressedStructured, MessageType26BroadcastStructured, \
-    MessageType26BroadcastUnstructured, MessageType22Addressed, MessageType22Broadcast, to_turn, from_turn
+from pyais.messages import (MSG_CLASS, MessageType5, MessageType6,
+                            MessageType18, MessageType22Addressed,
+                            MessageType22Broadcast, MessageType24PartA,
+                            MessageType24PartB,
+                            MessageType25AddressedStructured,
+                            MessageType25AddressedUnstructured,
+                            MessageType25BroadcastStructured,
+                            MessageType25BroadcastUnstructured,
+                            MessageType26AddressedStructured,
+                            MessageType26BroadcastStructured,
+                            MessageType26BroadcastUnstructured, from_turn,
+                            to_turn)
 from pyais.stream import ByteStream
-from pyais.util import bytes2bits, bits2bytes, b64encode_str
+from pyais.util import b64encode_str, bits2bytes, bytes2bits
 
 
 def ensure_type_for_msg_dict(msg_dict: typing.Dict[str, typing.Any]) -> None:
@@ -679,6 +689,12 @@ def test_msg_type_27(self):
 
         ensure_type_for_msg_dict(msg)
 
+    def test_msg_type_27_signed(self):
+        msg = decode('!AIVDO,1,1,,A,K01;FQh?PbtE3P00,0*75').asdict()
+        assert msg['mmsi'] == 1234567
+        assert msg['lon'] == -13.368333
+        assert msg['lat'] == -50.121667
+
     def test_broken_messages(self):
         # Undefined epfd
         assert decode(b"!AIVDM,1,1,,B,4>O7m7Iu@<9qUfbtm`vSnwvH20S8,0*46").asdict()['epfd'] == EpfdType.Undefined