check that all GeometryMixin subclasses have a geometry field

src/c3nav/mapdata/apps.py

@@ -1,14 +1,18 @@
+from typing import List
+
 from django.apps import AppConfig
+from django.core.exceptions import FieldDoesNotExist
 from django.db import models
+from django.utils.translation import ugettext_lazy as _
 
 
 class MapdataConfig(AppConfig):
     name = 'c3nav.mapdata'
 
-    def _get_submodels(self, cls: type):
+    def _get_submodels(self, cls: type) -> List[models.Model]:
         submodels = []
         for subcls in cls.__subclasses__():
-            if issubclass(subcls, models.Model):
+            if issubclass(subcls, models.Model) and not subcls._meta.abstract:
                 submodels.append(subcls)
             submodels.extend(self._get_submodels(subcls))
         return submodels
@@ -21,6 +25,14 @@ class MapdataConfig(AppConfig):
         from c3nav.mapdata.models.geometry.base import GeometryMixin, GEOMETRY_MODELS
         for cls in self._get_submodels(GeometryMixin):
             GEOMETRY_MODELS[cls.__name__] = cls
+            geometry = None
+            try:
+                geometry = cls._meta.get_field('geometry')
+            except FieldDoesNotExist:
+                pass
+
+            if geometry is None:
+                raise TypeError(_('Model %s has GeometryMixin as base class but has no geometry field.') % cls)
 
         from c3nav.mapdata.models.geometry.section import SectionGeometryMixin, SECTION_MODELS
         for cls in self._get_submodels(SectionGeometryMixin):