add MapUpdate

src/c3nav/mapdata/models/update.py

@@ -0,0 +1,22 @@
+from django.conf import settings
+from django.db import models
+from django.utils.translation import ugettext_lazy as _
+
+
+class MapUpdate(models.Model):
+    """
+    A map update. created whenever mapdata is changed.
+    """
+    datetime = models.DateTimeField(auto_now_add=True, db_index=True)
+    user = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, on_delete=models.PROTECT)
+    type = models.CharField(max_length=32)
+
+    class Meta:
+        verbose_name = _('Map update')
+        verbose_name_plural = _('Map updates')
+        default_related_name = 'mapupdates'
+        get_latest_by = 'datetime'
+
+    def save(self, **kwargs):
+        if self.pk is not None:
+            raise TypeError