[TYPO3-dev] What is the purpose of sysexts?

[Franz Holzinger]

Ries van Twisk a écrit :
> 
> On May 20, 2009, at 2:36 AM, Franz Holzinger wrote:
> 
>> Ries van Twisk a écrit :
>>> On May 19, 2009, at 12:08 PM, Steffen Kamper wrote:
>>>
>>>> Hi,
>>>>
>>>> Niels Pardon schrieb:
>>>>> Hi!
>>>>>
>>>>> While following the threads about adding some extensions as sysexts in
>>>>> the core and dev newsgroups I asked myself what the purpose of those
>>>>> sysexts is.
>>>>>
>>>>
>>>> long post, short answer:
>>>>
>>>> Main purpose is that the maintainance of sys extension is done by the
>>>> core team. They will always use the latest API calls and should be a
>>>> good example of "how-to-do"
>>>>
>>>> vg Steffen
>>>
>>>
>>> I believe that once was said (on a typo3 core meeting on IRC)  a sysext
>>> depends on a specific core version.
>>>
>>> For example you cannot put css_styled_content on TER because the latest
>>> version that is compatible with 4.2.0
>>> will properly not work on older versions of TYPO3. Same goes for DBAl
>>> and other highly TYPO3 version depend extensions.
>> No, this is wrong. You can add a dependancy of TYPO3 4.2.0 to each
>> extension. This is no reason to define an extension as a sysext.
>>
>> I would favour to have a small TYPO3 Core. Also in the past many
>> extensions have been removed from the Core for this reason.
>>
>> - Franz
>>
> 
> Franz, I was writing down what I remembered from a IRC core meeting
> a couple of years ago. Since a sysextension depends on a specific 
> version TYPO3 (API calls)
> it can break a TYPO3 installation badly with PHP errors and unusable BE
> when a user decided to ignore the requirement, something that is possible
> using the extension manager.

Hello Ries,

every extension which has a dependancy on TYPO3 4.2. will break the 
whole system if it is installed. The EM must take care to avoid this.

> For this reason I believe we have several extensions delivered in core
> rather then put in TER, even though TER 'supports' TYPO3 versions.

This is not the best decision. It would have been better to improve the EM.

> Also the extensions manager always tries to install the latest version
> and not a version that fits a TYPO3 version, whish makes it more 
> problematic
> and error prone.
The EM lacks to check the installed version of TYPO3.
IMHO it would be better to improve the EM than to ship TYPO3 with so 
many extensions which only few experts will need.

- Franz