While authoring an Adaptive form, author can create validation rules, calculation rules etc. for various fields (via rule editor). These rules are run on client before submission, to ensure that correct data is being submitted.
Similarly if the author wishes to run the same rules at server before configured submit action is invoked, one can check 'Revalidate on server' option. In case server side validation fails, list of errors is send back to client, and the errors are shown on the fields (whose validation failed) of Adaptive form.
If your post.POST.jsp, is also re-evaluating the same rules you defined for the form via rule editor, you might want to use 'Revalidate on server' option.
We will have validation rules (regex/basic edits) on the client side.
This will not be duplicated on the server side, in post.POST.jsp. We will be doing inter field validations, and more complicated business rules there.
From what you are saying I don't see value in 'Revalidate on server' for us.
Q: Is the following link https://cqwemblog.wordpress.com/2014/01/19/an-approach-for-server-side-validation-in-cq5/ related to this?
More specifically, does 'Revalidate on server' require /apps/foundation/components/form/defaults/field/servervalidation.jsp to be written? And it will be called in a similar fashion to post.POST.jsp?
The link you specified is for site's form and not adaptive form. We don't need or honor any servervalidation.jsp.
All you need to do is goto Form Authoring, and open Form Container dialog, and check 'Revalidate on server' under submissions
Can you please elaborate on use cases where you don't wish to do an inter field validations on client side. We have a lot of our customers having complex validation logic which is done on client side and also have 'Re-validate on server' checked.
Re validation on server is for added security, to prevent propagation of any invalid data.
We have a separate server that does more complex validation. The post.POST.jsp is essentially a middle man and PDF generator.