ServiceNow Catalog Client Script for Async Server Validation

Create a ServiceNow Catalog Client Script (onSubmit) that validates a selected server's related parent records asynchronously. It prevents submission if operational servers are found (displaying an alert) and allows submission otherwise.

Prompt

Role & Objective

Act as a ServiceNow Client Scripting expert. Create an onSubmit Catalog Client Script that validates a selected server reference variable against related CMDB records using asynchronous GlideAjax.

Operational Rules & Constraints

1. Trigger: The script must run on

   onSubmit

   .
2. Input: Identify the reference variable (e.g.,

   select_server

   ) referring to

   cmdb_ci_server

   .
3. Async Check:
   • Use

     g_form.getReference

     to fetch the server record and get its

     ip_address

     .
   • Use

     GlideAjax

     to call a server-side Script Include (e.g.,

     CheckOpStatus

     ).
   • Pass the

     ip_address

     to the Script Include.
4. Server-Side Logic (Context): The Script Include queries

   cmdb_rel_ci

   for parent records where

   child.ip_address

   matches the input IP and checks if `operational_status == '1'.
5. Response Handling:
   • If operational servers are found:
     • Parse the JSON response.
     • Display an alert box listing the names of the operational servers.
     • Clear the value of the reference variable (

       g_form.clearValue

       ).
     • Prevent form submission.
   • If no operational servers are found:
     • Allow the form to submit.
6. Asynchronous Submission Control:
   • Because

     GlideAjax

     is asynchronous, the initial

     onSubmit

     must return

     false

     to block submission while waiting.
   • Use a mechanism (e.g.,

     sessionStorage

     or global flags) to persist the validation state across the callback.
   • If validation passes (no operational servers), programmatically trigger

     g_form.submit()

     or

     g_form.save()

     within the callback.
   • Ensure flags are cleared after submission to prevent loops.

Anti-Patterns

• Do not use synchronous

  getXMLWait()

  as it blocks the browser.
• Do not rely solely on in-memory variables if the page might reload or state needs to persist across the async boundary without complex flag management.

Interaction Workflow

1. User clicks Submit.
2. Script checks if server is selected. If not, allow submit.
3. If selected, initiate GlideAjax call and return

   false

   .
4. On callback:
   • If error/block condition: Alert user, clear field, keep submission blocked.
   • If success condition: Set success flag, trigger

     g_form.submit()

     .

Triggers

• servicenow catalog client script onsubmit validation
• prevent submission based on server status
• glideajax check before submit
• alert and block catalog request
• check parent server operational status