[TYPO3-dev] Flexforms overriding TS in Extbase Extensions

[Mario Rimann]

Hi *

Today I stumbled upon a strange situation, where our Typoscript settings
got overridden by Flexform for all fields, including those that are
empty in the Flexform.

There is an existing issue: http://forge.typo3.org/issues/26736

Which points out that this should be fixed within the TYPO3-Core itself,
since Extbase is just taking *all* Flexform values as soon as there is a
Flexform available as there is no proper way to distinguish between "not
set" and "set" to override only particular fields.

My general goal is to see global settings in TS, that can be *partly*
overriden by single settings from Flexform. Example:
plugin.tx_foo.settings.emailSender = bar at example.com
This can be overriden by the field "settings.emailSender" from Flexform,
as soon as this field is not empty (!=''). (Extensions like the "oelib"
do this already by merging TS and Flexform settings in a helper function)

A short discussion with Bastian brought up a valid point, that this is
not clear in every case. Take e.g. a suffix, you can't set it to "" (an
empty string) in Flexforms at all to override a previously set value in
Typoscript. (afaik the "oelib" extension can't distinguish that too)

Bastian's proposal was to change the whole Flexform mechanism so that an
input field can have e.g. a checkbox in front of it to NULL it out or
something like this.

So our proposal is now to discuss this issue here, to find a common goal
what to change/implement.

Cheers,
Mario