Add retry decorator for DB locked errors, remove coach hook cleaning …

…up syncs

kolibri/core/utils/lock.py

@@ -3,6 +3,7 @@
 
 from django.db import connection
 from django.db import transaction
+from django.utils.functional import wraps
 
 
 class DummyOperation(object):
@@ -73,3 +74,24 @@ def db_lock():
                 vendor=connection.vendor
             )
         )
+
+
+def retry_on_db_lock(func, retries=5):
+    """
+    Decorator that retries a function if it fails due to a database lock.
+    """
+
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        attempts = 0
+        while True:
+            try:
+                attempts += 1
+                result = func(*args, **kwargs)
+                break
+            except OperationalError as e:
+                if "database is locked" not in str(e) or attempts >= retries:
+                    raise e
+        return result
+
+    return wrapper

kolibri/plugins/coach/kolibri_plugin.py

@@ -5,8 +5,6 @@
 import logging
 
 from kolibri.core.auth.constants.user_kinds import COACH
-from kolibri.core.device.utils import get_device_setting
-from kolibri.core.discovery.hooks import NetworkLocationDiscoveryHook
 from kolibri.core.hooks import NavigationHook
 from kolibri.core.hooks import RoleBasedRedirectHook
 from kolibri.core.webpack import hooks as webpack_hooks
@@ -59,19 +57,3 @@ def plugin_data(self):
         return {
             "practice_quizzes_exist": practice_quizzes_exist,
         }
-
-
-@register_hook
-class NetworkDiscoveryForSoUDHook(NetworkLocationDiscoveryHook):
-    def on_disconnect(self, network_location):
-        """
-        :type network_location: kolibri.core.discovery.models.NetworkLocation
-        """
-        from kolibri.core.auth.tasks import queue_soud_server_sync_cleanup
-
-        if (
-            not get_device_setting("subset_of_users_device")
-            and network_location.subset_of_users_device
-        ):
-            logger.debug("SoUD listener: triggering cleanup of SoUD sync")
-            queue_soud_server_sync_cleanup(network_location.instance_id)

kolibri/plugins/learn/kolibri_plugin.py

@@ -15,6 +15,7 @@
 from kolibri.core.discovery.hooks import NetworkLocationDiscoveryHook
 from kolibri.core.hooks import NavigationHook
 from kolibri.core.hooks import RoleBasedRedirectHook
+from kolibri.core.utils.lock import retry_on_db_lock
 from kolibri.core.webpack import hooks as webpack_hooks
 from kolibri.plugins import KolibriPluginBase
 from kolibri.plugins.hooks import register_hook
@@ -109,6 +110,7 @@ def node_url(self, node):
             )
 
 
+@retry_on_db_lock
 def request_soud_sync(network_location):
     """
     :type network_location: kolibri.core.discovery.models.NetworkLocation