# Remove ExternalIdentifier

* adds removing of ExternalIdentifier entries if a BaseObject is removed from the database
* removes unused import statements
* adds ExternalIdentifier view to admin backend

konova/models/object.py

@@ -146,6 +146,33 @@ class BaseObject(BaseResource, DeletableObjectMixin):
     class Meta:
         abstract = True
 
+    def delete(self, using=None, keep_parents=False):
+        """ Base deleting of a BaseObject instance
+
+        Args:
+            using:
+            keep_parents:
+
+        Returns:
+
+        """
+        self.__delete_external_identifier()
+        super().delete(using, keep_parents)
+
+    def __delete_external_identifier(self):
+        """ Checks on existing external identifier linking and drops them
+
+        Returns:
+
+        """
+        from api.models import ExternalIdentifier
+        try:
+            external_identifier = ExternalIdentifier.objects.filter(internal_id=self.id)
+            external_identifier.delete()
+        except ObjectDoesNotExist:
+            pass
+
+
     @abstractmethod
     def set_status_messages(self, request: HttpRequest):
         raise NotImplementedError