[pgAdmin4][patch] sqleditor connection status minor patch

[Aditya Toshniwal]

Hi Hackers,

PFA a minor patch for sqleditor. When you disconnect the server with an
open sqleditor tab, exception occurs at the back end. Also, after
connecting server, the sqleditor is not able to connect back because of the
exception. The patch is to handle it.
Kindly review.

Thanks and Regards,
Aditya Toshniwal
Software Engineer | EnterpriseDB Software Solutions | Pune
"Don't Complain about Heat, Plant a tree"

diff --git a/web/pgadmin/tools/sqleditor/__init__.py b/web/pgadmin/tools/sqleditor/__init__.py
index 013e4dc..a9460dd 100644
--- a/web/pgadmin/tools/sqleditor/__init__.py
+++ b/web/pgadmin/tools/sqleditor/__init__.py
@@ -1480,19 +1480,24 @@ def query_tool_status(trans_id):
     if conn and trans_obj and session_obj:
         status = conn.transaction_status()
 
-        # Check for the asynchronous notifies statements.
-        conn.check_notifies(True)
-        notifies = conn.get_notifies()
+        if status is not None:
+            # Check for the asynchronous notifies statements.
+            conn.check_notifies(True)
+            notifies = conn.get_notifies()
 
-        return make_json_response(
-            data={
-                'status': status,
-                'message': gettext(
-                    CONNECTION_STATUS_MESSAGE_MAPPING.get(status),
-                ),
-                'notifies': notifies
-            }
-        )
+            return make_json_response(
+                data={
+                    'status': status,
+                    'message': gettext(
+                        CONNECTION_STATUS_MESSAGE_MAPPING.get(status),
+                    ),
+                    'notifies': notifies
+                }
+            )
+        else:
+            return internal_server_error(
+                errormsg=gettext("Transaction status check failed.")
+            )
     else:
         return internal_server_error(
             errormsg=gettext("Transaction status check failed.")