WIP on ws gateway, it now works

[loctrkd.git] / gps303 / zmsg.py

diff --git a/gps303/zmsg.py b/gps303/zmsg.py
index 56392007f1ff74ecd61cf59b8a95b1b9c2c06c48..0ccef007db6a0ddc5a9491b6d661ec89a63c1a57 100644 (file)
--- a/gps303/zmsg.py
+++ b/gps303/zmsg.py
@@ -1,9 +1,11 @@
 """ Zeromq messages """
 
+from datetime import datetime, timezone
+from json import dumps, loads
 import ipaddress as ip
 from struct import pack, unpack
 
-__all__ = "Bcast", "Resp"
+__all__ = "Bcast", "LocEvt", "Resp"
 
 
 def pack_peer(peeraddr):
@@ -58,15 +60,20 @@ class _Zmsg:
             ),
         )
 
+    def __eq__(self, other):
+        return all(
+            [getattr(self, k) == getattr(other, k) for k, _ in self.KWARGS]
+        )
+
     def decode(self, buffer):
-        raise RuntimeError(
-            self.__class__.__name__ + "must implement `encode()` method"
+        raise NotImplementedError(
+            self.__class__.__name__ + "must implement `decode()` method"
         )
 
     @property
     def packed(self):
-        raise RuntimeError(
-            self.__class__.__name__ + "must implement `encode()` method"
+        raise NotImplementedError(
+            self.__class__.__name__ + "must implement `packed()` property"
         )
 
 
@@ -119,3 +126,53 @@ class Resp(_Zmsg):
     def decode(self, buffer):
         self.imei = buffer[:16].decode()
         self.packet = buffer[16:]
+
+
+class LocEvt(_Zmsg):
+    """Zmq message with original or approximated location from lookaside"""
+
+    KWARGS = (
+        ("imei", "0000000000000000"),
+        ("devtime", datetime(1970, 1, 1, tzinfo=timezone.utc)),
+        ("lat", 0.0),
+        ("lon", 0.0),
+        ("is_gps", True),
+    )
+
+    # This message is for external consumption, so use json encoding,
+    # except imei that forms 16 byte prefix that can be used as the
+    # topic to subscribe.
+    @property
+    def packed(self):
+        return (
+            self.imei.encode()
+            + dumps(
+                {
+                    "devtime": str(self.devtime),
+                    "latitude": self.lat,
+                    "longitude": self.lon,
+                    "is-gps": self.is_gps,
+                }
+            ).encode()
+        )
+
+    # And this is full json that can be sent over websocket etc.
+    @property
+    def json(self):
+        return dumps(
+            {
+                "imei": self.imei,
+                "devtime": str(self.devtime),
+                "latitude": self.lat,
+                "longitude": self.lon,
+                "is-gps": self.is_gps,
+            }
+        )
+
+    def decode(self, buffer):
+        self.imei = buffer[:16].decode()
+        json_data = loads(buffer[16:])
+        self.devtime = datetime.fromisoformat(json_data["devtime"])
+        self.lat = json_data["latitude"]
+        self.lon = json_data["longitude"]
+        self.is_gps = json_data["is-gps"]