JS-evaluation in ajax-enabled forms

[asaage]

Affected version(s)

5.3.7

Description

When a form is ajax enabled, script-tags are not loaded and executed (exept in the initial page-load).
Not sure, if that is by design, a known limitation or just a missing eval(); somewhere.
It occured first to me in a mp_form but the problem seems to be in the xhr-handler.
Such a script-tag exists especially in the captcha-field/widget (maybe others too).
To recreate: make a form, enable ajax, add an email-field, a captcha-field and a submit. In the FE force a validation error by submitting example@foo (mailaddress without tld). As a result the form will return with the usual errormessage but the captcha-field will be visible and not hidden as usual.

related:

• https://community.contao.org/de/showthread.php?86809-mp_forms-mit-captcha
• javascript-loading / execution in ajax-enabled forms terminal42/contao-mp_forms#82

[fritzmg]

I can confirm the issue.

[ausi]

To fix this we should IMO not evaluate the <script>s of the ajax response, but instead add an ajax-form-onload event listener to the captcha script.

[fritzmg]

Or may be implement it as a mutation observer instead?

[asaage]

... add ... event listener to the captcha script.

I would prefer if a solution does not depend on a special widget.
If you add js to other widgets (like for example displaying the value of a range-slider) you would face the same problem again.

[fritzmg]

@asaage The solution will be done within the captcha widget's JavaScript. And any other widget of course needs to implement their JavaScript in a way that is independent from whether the form is submitted via AJAX or not (and that has always been the case).

[asaage]

i figure, that would probably not solve the original issue i had in mp_forms and complicate enhancing formfield templates with js unneccessary 🤷‍♂️

[fritzmg]

that would probably not solve the original issue i had in mp_form

May be ask on the Contao Community Forum or Community Slack for help regarding that issue.

and complicate enhancing formfield templates with js unneccessary 🤷‍♂️

I am not sure what you mean here. May be also ask on the Contao Community Forum or Community Slack for advice on how to handle forms that are submitted via AJAX properly (this is a general topic unrelated to Contao itself).