[TYPO3-50-general] XML schema for PackageInfo.xsd

[David Bruehlmeier]

Hi all,

thanks for your feedback.

I have now created a RelaxNG schema trying to incorporate your feedback 
as well as the discussions and drafts on forge [1].

The schema:
http://www.bruehlmeier.com/fileadmin/flow3/Package.rng

And an example XML:
http://www.bruehlmeier.com/fileadmin/flow3/Package.xml


Some comments:

1. I have seen on forge that the name PackageInfo.xml doesn't seem to be 
untouchable. What about just naming it Package.xml?

2. The namespace would be xmlns="http://typo3.org/ns/2008/flow3/package"

3. The root element would be just <package>

4. I would refrain from having a version "history" in this file, as 
suggested in one of the files on forge (multiple <version> elements). 
IMO, it is up to the Repository to version the packages and it should 
not be done within this single file.

5. The schema is less permissive now, most of the elements are required.

6. Instead of introducing <author>, <maintainer> et al, why not "borrow" 
the concept from OASIS xPIL [2] and introduce a <party> element with 
zero or more <person> and/or <company> elements? Each party can have a 
"role" attribute, like "LeadDeveloper", "Maintainer", "Sponsor", etc. Of 
course, we don't need full-fledged xPIL elements, but why re-invent the 
wheel? Something like "roles" was also suggested by Ingo Renner for 4.x 
on forge.

7. Each constraint (depends/conflicts/suggests) can contain three 
different elements:
* <package>
* <component> (was suggested by Robert on forge)
* <system>

8. The <system> element has a "type" attribute and only allows for 
parameters which can actually be checked in PHP:
* PHP: Checked with phpversion()
* PHPExtension: Checked with php_uname()
* Memory: Checked with memory_get_usage()

9. All constraints can have an (optional) minVersion and/or an 
(optional) maxVersion. The versions are defined to be inclusive, so 
checking should be easy using version_compare(). No operator signs are 
needed as suggested on forge.

10. Please use ISO8601 [3] only when representing dates and or times. It 
is a built-in type in both XSD and RNG and will never cause trouble. I 
suggest the full representation including time zone, such as: 
2008-04-22T17:23:09Z

11. As for the question XSD or RNG: I get the feeling that RNG seems to 
be the choice that is better accepted for FLOW3. In some circumstances 
(like for the FLOW3 Development Environment, which is written in Java), 
it would still be nice to have an XSD. What about if we declare the RNG 
schema to be normative, but still offer a non-normative XSD which can 
easily be generated from RNG using the Trang Converter [4]. It would 
look like this:

http://www.bruehlmeier.com/fileadmin/flow3/Package.xsd


Regards,
Dave


[1] http://forge.typo3.org/issues/show/14
[2] http://www.oasis-open.org/committees/ciq/
[3] http://en.wikipedia.org/wiki/ISO_8601
[4] http://www.thaiopensource.com/relaxng/trang.html