fix: delete anonymous sessions right after pausing (#907)

Author: olevski

components/renku_data_services/notebooks/blueprints.py

@@ -432,7 +432,7 @@ async def _handler(
                     extraContainers=extra_containers,
                     initContainers=extra_init_containers,
                     extraVolumes=extra_volumes,
-                    culling=get_culling(resource_pool, self.nb_config),
+                    culling=get_culling(user, resource_pool, self.nb_config),
                     authentication=Authentication(
                         enabled=True,
                         type=AuthenticationType.oauth2proxy

components/renku_data_services/notebooks/core_sessions.py

@@ -435,12 +435,20 @@ async def repositories_from_session(
     return repositories_from_project(project, git_providers)
 
 
-def get_culling(resource_pool: ResourcePool, nb_config: NotebooksConfig) -> Culling:
+def get_culling(
+    user: AuthenticatedAPIUser | AnonymousAPIUser, resource_pool: ResourcePool, nb_config: NotebooksConfig
+) -> Culling:
     """Create the culling specification for an AmaltheaSession."""
     idle_threshold_seconds = resource_pool.idle_threshold or nb_config.sessions.culling.registered.idle_seconds
-    hibernation_threshold_seconds = (
-        resource_pool.hibernation_threshold or nb_config.sessions.culling.registered.hibernated_seconds
-    )
+    if user.is_anonymous:
+        # NOTE: Anonymous sessions should not be hibernated at all, but there is no such option in Amalthea
+        # So in this case we set a very low hibernation threshold so the session is deleted quickly after
+        # it is hibernated.
+        hibernation_threshold_seconds = 1
+    else:
+        hibernation_threshold_seconds = (
+            resource_pool.hibernation_threshold or nb_config.sessions.culling.registered.hibernated_seconds
+        )
     return Culling(
         maxAge=format_duration(timedelta(seconds=nb_config.sessions.culling.registered.max_age_seconds)),
         maxFailedDuration=format_duration(timedelta(seconds=nb_config.sessions.culling.registered.failed_seconds)),
@@ -529,7 +537,7 @@ async def patch_session(
         patch.spec.affinity = node_affinity_from_resource_class(rc, nb_config.sessions.affinity_model)
         # Priority class (if a quota is being used)
         patch.spec.priorityClassName = rc.quota
-        patch.spec.culling = get_culling(rp, nb_config)
+        patch.spec.culling = get_culling(user, rp, nb_config)
 
     # If the session is being hibernated we do not need to patch anything else that is
     # not specifically called for in the request body, we can refresh things when the user resumes.