Raise exception to not allow project to disconnect labeling front end

Author: Val Brodsky

libs/labelbox/src/labelbox/orm/db_object.py

@@ -192,10 +192,10 @@ def connect(self, other):
         self.source.client.execute(query_string, params)
 
     def disconnect(self, other):
+        """ Disconnects source object of this manager from the `other` object. """
         if not self.config.disconnect_supported:
             raise OperationNotSupportedException(
                 "Disconnect is not supported for this relationship")
-        """ Disconnects source object of this manager from the `other` object. """
 
         query_string, params = query.update_relationship(
             self.source, other, self.relationship, "disconnect")

libs/labelbox/src/labelbox/schema/project.py

@@ -132,7 +132,9 @@ class Project(DbObject, Updateable, Deletable):
     # Relationships
     created_by = Relationship.ToOne("User", False, "created_by")
     organization = Relationship.ToOne("Organization", False)
-    labeling_frontend = Relationship.ToOne("LabelingFrontend")
+    labeling_frontend = Relationship.ToOne(
+        "LabelingFrontend",
+        config=Relationship.Config(disconnect_supported=False))
     labeling_frontend_options = Relationship.ToMany(
         "LabelingFrontendOptions", False, "labeling_frontend_options")
     labeling_parameter_overrides = Relationship.ToMany(

libs/labelbox/tests/integration/test_labeling_frontend.py

@@ -1,6 +1,8 @@
-from labelbox import LabelingFrontend
 import pytest
 
+from labelbox import LabelingFrontend
+from labelbox.exceptions import OperationNotSupportedException
+
 
 def test_get_labeling_frontends(client):
     filtered_frontends = list(
@@ -18,5 +20,5 @@ def test_labeling_frontend_connecting_to_project(project):
     project.labeling_frontend.connect(default_labeling_frontend)
     assert project.labeling_frontend() == default_labeling_frontend
 
-    project.labeling_frontend.disconnect(default_labeling_frontend)
-    assert project.labeling_frontend() == None
+    with pytest.raises(OperationNotSupportedException):
+        project.labeling_frontend.disconnect(default_labeling_frontend)