attachment size on workspace

Raze00 · ‎01-05-2026

Hi i want to display the message as soon as possible whenever an attachment is attached to the case and the combine size of attachments exceed 18mb then i want to show the error message immediately is this possible?

Ankur Bawiskar · ‎01-08-2026

@Raze00

Small change in my Script & it worked fine for me

-> I added size bytes for the current file also, I forgot it earlier

(function executeRule(current, previous /*null when async*/ ) {
    // Define your limit in bytes (e.g., 10MB)
    var maxSize = 18 * 1024 * 1024; // 18 MB

    var totalSize = 0;
    var gr = new GlideRecord("sys_attachment");
    gr.addQuery("table_sys_id", current.table_sys_id);
    gr.query();
    while (gr.next()) {
        totalSize = totalSize + parseInt(gr.size_bytes);
    }

    totalSize = totalSize + parseInt(current.size_bytes);

    if (totalSize > maxSize) {
        gs.addErrorMessage('Total Attachment size exceeds the limit of 18 MB.'); // User-friendly message
        current.setAbortAction(true); // Prevents the attachment from being saved
    }
})(current, previous);

Output: I tried to add 3rd file and it exceeded 18MB and error message thrown and file not added

💡 If my response helped, please mark it as correct ✅ and close the thread 🔒— this helps future readers find the solution faster! 🙏

Regards,
Ankur
✨ Certified Technical Architect || ✨ 10x ServiceNow MVP || ✨ ServiceNow Community Leader

View solution in original post

UmesH77 · ‎01-05-2026

Hello @Raze00 ,

In ServiceNow:

Attachments are saved after upload
Client scripts cannot read attachment sizes directly
Total size exists only on the server

So the solution must be:

Client Script (detect upload) → Script Include (calculate size) → Client response

You have to go Like this .
User attaches file
↓
onSubmit / onChange (Client Script)
↓
GlideAjax call
↓
Script Include (sum attachment sizes)
↓
Return size
↓
Show error message immediately

it is possible, but only by calling a Script Include via GlideAjax from a Client Script to calculate the total attachment size server-side and return it immediately to the UI.
if you want script include just reply I will provide that as well.

If my solution is helpful , Accept it as solution 🙏or mark is as helpful as well👍.
Regards,
UmesH
Technical Consultant.

Raze00 · ‎01-05-2026

Hi, Yes if you can provide it. Thankyou.

Ankur Bawiskar · ‎01-05-2026

@Raze00

did you try to use before insert BR on sys_attachment table and show some info message?

what did you try so far and where are you stuck?

💡 If my response helped, please mark it as correct ✅ and close the thread 🔒— this helps future readers find the solution faster! 🙏

Regards,
Ankur
✨ Certified Technical Architect || ✨ 10x ServiceNow MVP || ✨ ServiceNow Community Leader

Raze00 · ‎01-06-2026

Hi ankur, i have created a br on hr core table as display br whenever the attachment is added and agent saves the form or reload it the error will show. what i want is that message to display immediately after the attachment is added because sometimes agent wont save the form after uploading an attachment .