Acquire a lock regardless of the authentication sources while getting the database server connection.

web/pgadmin/utils/locker.py

@@ -0,0 +1,50 @@
+##########################################################################
+#
+# pgAdmin 4 - PostgreSQL Tools
+#
+# Copyright (C) 2013 - 2022, The pgAdmin Development Team
+# This software is released under the PostgreSQL Licence
+#
+##########################################################################
+
+"""
+Kerberos Environment Locker class
+"""
+
+from threading import Lock
+from os import environ
+from flask import session, current_app
+
+import config
+from pgadmin.utils.constants import KERBEROS
+
+
+class ConnectionLocker:
+    """Implementing lock while setting/unsetting
+     the Kerberos environ variables."""
+    lock = Lock()
+
+    def __init__(self, _is_kerberos_conn=False):
+        self.is_kerberos_conn = _is_kerberos_conn
+
+    def __enter__(self):
+        if config.SERVER_MODE:
+            current_app.logger.info("Waiting for a lock.")
+            self.lock.acquire()
+            current_app.logger.info("Acquired a lock.")
+
+            if session['auth_source_manager']['current_source'] == \
+                KERBEROS and 'KRB5CCNAME' in session \
+                    and self.is_kerberos_conn:
+                environ['KRB5CCNAME'] = session['KRB5CCNAME']
+            else:
+                environ.pop('KRB5CCNAME', None)
+
+        return self
+
+    def __exit__(self, type, value, traceback):
+        if config.SERVER_MODE:
+            environ.pop('KRB5CCNAME', None)
+            if self.lock.locked():
+                current_app.logger.info("Released a lock.")
+                self.lock.release()