Disabled settings trigger errors upon saving

[leofeyer]

Affected version(s)

Contao 4.10

Description

Since #1382, settings defined in the app configuration are disabled in the back end. When trying to save the form, however, these fields trigger errors:

[ausi]

Adding $GLOBALS['TL_DCA']['tl_settings']['fields'][$field]['eval']['mandatory'] = false; to

contao/core-bundle/src/EventListener/DataContainer/DisableAppConfiguredSettingsListener.php

Lines 55 to 57 in 5324c34

	$GLOBALS['TL_DCA']['tl_settings']['fields'][$field]['eval']['disabled'] = true;
	$GLOBALS['TL_DCA']['tl_settings']['fields'][$field]['eval']['helpwizard'] = false;
	$GLOBALS['TL_DCA']['tl_settings']['fields'][$field]['xlabel'][] = [self::class, 'renderHelpIcon'];

fixed the issue in my test.

[fritzmg]

But that's not really how disabled fields are supposed to work, is it? 🤔

[ausi]

I don’t know. Setting a disabled field to mandatory could be seen as a misconfiguration I guess?

[fritzmg]

Yeah, I guess you are right.

[ausi]

But intuitively I would also expect the disabled option to take precedence over all other settings.

To make this work we could change

contao/core-bundle/src/Resources/contao/library/Contao/Widget.php

Lines 809 to 812 in af6fbee

	if (!$this->mandatory)
	{
	return '';
	}

to if (!$this->mandatory || !$this->blnSubmitInput)

[leofeyer]

Should we not return immediately if we know that the widget does not submit anything?

	protected function validator($varInput)
	{
		if (!$this->submitInput())
		{
			return null;
		}

		if (\is_array($varInput))

[leofeyer]

And is this not the actual cause of the error?

contao/core-bundle/src/Resources/contao/classes/DataContainer.php

Lines 375 to 388 in af6fbee

	// Validate and save the field
	if (\in_array($this->strInputName, $paletteFields) || Input::get('act') == 'overrideAll')
	{
	$objWidget->validate();
	if ($objWidget->hasErrors())
	{
	// Skip mandatory fields on auto-submit (see #4077)
	if (!$objWidget->mandatory || $objWidget->value != '' || Input::post('SUBMIT_TYPE') != 'auto')
	{
	$this->noReload = true;
	}
	}
	elseif ($objWidget->submitInput())

Why validate a widget that does not submit any input?

[ausi]

I honestly don’t know for what submitInput() is meant to be used for. Maybe the widget could get the value from somwhere else but still needs to be validated and saved?

I think I would just extend the check in

contao/core-bundle/src/Resources/contao/library/Contao/Widget.php

Line 809 in af6fbee

if (!$this->mandatory)

this should most likely not break existing code.

[aschempp]

I don't think returning on empty content is correct (as suggested by @ausi). We must not validate a widget that does not submit input (which is the case if it is disabled, or the widget has only presentational purpose).

[leofeyer]

That is what I think, too.

[ausi]

I just looked at this again: If $objWidget->submitInput() is false the save method is never called. So I think @aschempp is right “We must not validate a widget that does not submit input” 👍