Regex Variable Validation on mandatory variables [workaround]

Hi there,

With the release of Madrid, a nice new feature was introduced: "Variable Validation Regex". In short, you can add a validation on (single-line text) variables through selecting a record from a reference field. The reference field displaying regex choices. This way, you can easily add validations, re-use validations, you won't have to write Catalog Client Scripts over and over anymore, etc.. You can read more about this in one of my previous articles: Service Portal Catalog Items: Regex Field Validation [Madrid].

Issue

Unfortunately though, this new feature does not work flawlessly. There's a nasty bug (and still on New York)… When applying the Regex Variable Validation on a mandatory variable, and the validation triggered to display the error message, the user gets stuck when trying to submit the Catalog Item. For non-mandatory variables, this is not an issue.

ServiceNow has this listed as a PRB, PRB1355430.
"If there's a mandatory variable validated by a regex, it's still possible to submit the catalog item, however, it'll get stuck on submit.
If the variable isn't mandatory, it'll be validated correctly and the item can't be submitted"

There is no targeted fix at this moment.

Workaround

Because this is a nice feature, saves creating a Catalog Client Script over and over, a no/low-code admin can use this as well, we wanted to use this feature a.s.a.p.. During our investigation on this issue, we came up with a workaround. It's not a 100% workaround, though very workable. In short: if the mandatory variable is filled, change the mandatory attribute to false. This prevents the Catalog Item from getting stuck if the Regex Variable Validation wasn't correct and the user tried to submit the Catalog Item.

So how to make a mandatory variable not mandatory? There are multiple situations.
- A variable which is made mandatory on the variable itself, thru the mandatory flag
- A variable which is conditionally made mandatory thru Catalog UI Policies and Catalog UI Policy Actions
- A variable which is conditionally made mandatory thru Catalog Client Scripts

Easiest are the variables which have the mandatory attribute flag checked on the variable itself, and no conditional mandatory in place. On these you could simply set up one Catalog UI Policy and Catalog UI Policy Action (no-code) or one Catalog Client Script (low-code). Don't forget to uncheck the mandatory attribute flag on the variable itself!

Catalog UI Policy and Catalog UI Policy Action

Catalog Client Script

Tougher are the conditional mandatory variables. Especially when there multi-level deep. Though, the basic thought will be the same. If the variable is filled, change the mandatory attribute flag to false. How to apply this is just a little different. Create two Catalog UI Policies with each one Catalog UI Policy Action. The first Catalog UI Policy Action is for if the variable is empty (and the Catalog UI Policy Action contains mandatory=true), and create a second Catalog UI Policy Action for if the variable is not empty. Two Catalog UI Policy Actions because… you have to uncheck the "Reverse if false" flag!

The regular Catalog UI Policy you would already have for conditional show/hide the variable:

Note: The "Clear the variable value" is used on the Catalog UI Policy Action. Read more about this in one of my previous articles: Clear the field value / Clear the variable value

Result

The result on the Service Portal with the conditional visible mandatory variable:

Variable being mandatory if left empty:

Variable made not mandatory if not empty, the actual workaround 🙂

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And that's it actually! Not a perfect / 100% workaround, though workable. And with this, the no-code Variable Validation Regex could be applied. Also, ones this issue is fixed by ServiceNow, you could easily revert the workarounds put in place. Too easily identify which Catalog UI Policies or Catalog Client Scripts have been set up for this workaround, for example mention the PRB in the description of the Catalog UI Policy / Catalog Client Script.

Kind regards,
Mark

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