chore: initial mobile api

apps/counter/api/mobile/serializers.py

@@ -34,3 +34,9 @@ class DeviceInfoMobileSerializer(serializers.ModelSerializer):
     def get_status(self, obj) -> int:
         return obj.online
 
+    def get_coordinate(self, obj):
+        if self.cur_device:
+            lon, lat = [self.cur_device.longitude, self.cur_device.latitude]
+            if lon and lat:
+                return [lon, lat]
+        return None