8 Apr
2016
8 Apr
'16
12:18 p.m.
On Fri, Apr 8, 2016 at 12:03 PM, Anca Luca <lucaa(a)xwiki.com> wrote:
Hello all,
I think the best would be 2, but it could be discussed on an app by app
basis and, in my opinion, the options need to be looked in the context of
what does it mean that an "application needs to pass to Nested Spaces".
This is my view on it:
- Requirement of a nested spaces version should be
done if the
functionalities of the application demand it (there is a feature that is
added to the functionality that needs nested spaces in order to work)
+1. IMO it's also very important to distinguish between:
* works with Nested Pages
* uses Nested Pages
At first we should just make sure the applications continue to work with
XWiki 7.2+, i.e. with Nested Pages enabled (without actually using the
Nested Pages feature). This is mostly a matter of using correctly the
entity reference APIs which have been supporting Nested Spaces from the
start (we just assumed so far that there is only one space). The APIs we
added after 7.2 are mostly helpers to ease the work with Nested Pages.
After we make the application work with XWiki 7.2+ we can discuss whether
it should use Nested Pages or not (i.e. whether it should create Nested
Pages or not). As Anca said, it needs to bring some value to the
application as perceived by its users. To give you an example, the reason I
would modify the File Manager to use Nested Pages is to have Access Rights
inheritance for folders and files.
Thanks,
Marius
- Note that application can *work* on nested
spaces without
*requiring* nested spaces (because of the general backwards
compatibility of nested spaces feature), this bullet above is about
requiring nested spaces.
- Even if previous versions can still be supported by an application
migrated to nested spaces, if this adds a lot of bloat and "if"s in the
code and extra complexity, the benefits are probably not worth it (it
should still be discussed though) - this would be option 0
- A particular case is when an application does not work on nested
spaces in its current form and needs to be modified to support nested
spaces. In this case, there needs to be an effort to find a reasonable
approach that would allow the application to work, with the same code,
on
both nested spaces and non-nested spaces (which could be possible
because
of the generic backwards compat of nested spaces)
Otherwise put, I am fine that there are applications on which we apply 2
(and even 3) , but there needs to be a good reason to pass to Nested
Spaces for an application, potentially joined by a validation discussion
with the community. If we decide we go to nested for an app, both 2 and 3
are fine. In such a case I would be against option 0 that Vincent
mentioned: adds complexity and bloats the code for an application, raises
the learning curve and it will be removed in the future.
Now please note that applying 2 means that if you're in the middle of the
developpement for a version of an application, on which some issues were
already fixed, and you want to move to a nested spaces version, it would be
nice to release current work first as the "last version before nested
spaces" and only then break compat. This is also valid for planning the
versions of the application: bugfixes / features that don't require nested
spaces should be planned in earlier, separate versions than features that
would require nested spaces.
On Fri, Apr 1, 2016 at 8:48 AM, Alexandru Cotiuga <
alexandru.cotiuga(a)xwiki.com> wrote:
Hello devs,
Since I already experimented the Nested Spaces behaviour on the Forum
application and there are other applications that might need it also, I
think it's time to start discussing this topic and to decide what
strategy
should be implemented on contrib applications.
What I have done in the Forum app was to handle both Pre NS and NS
versions
of XWiki, writing specific code for each case
(wrapped in if-else
statements), which proved to be the most complex and hard to maintain
way,
without much benefit. Sooner or later, everybody
will have a NS Xwiki
version and then all the support for Pre NS would become useless and then
the code should be cleaned, which would be a lot of work again.
Besides this already tried strategy, there are some others to be
discused:
1: Support both Pre NS and NS versions but in different branches.
2: Move to NS, but keep fixing bugs for Pre NS in a separate branch.
(This
is what I'm proposing)
3: Move to NS without any maintance on Pre NS.
4: Others?
In all the cases, a data migration should be performed.
Depends on what we understand by data migration: if the data format changes
(e.g. the data of the application needs to have a new hierarchical
structure because a functionality requires this hierarchy - e.g. inheriting
rights) then we need to have a data migration, as in take into account the
fact that there will be upgrades of the application, and that we should
have an unique format of data for the application in question (e.g. there
is no reason that the data structure is different between a user that has
installed the app on a fresh 7.4 and a user that has upgraded the
application from a previous version on a 7.4 xwiki).
If "data migration" is about just transforming all existing pages of
an/created by an application (which are terminal) into non-terminal pages,
then it should not be done unless there is a feature that requires it. I
think this data migration needs to be looked at as a change in the
application data structure (from a 2 levels hierarchy to an infinite
hierarchy) and should be done only if there is a functional benefit that
justifies it. In this context, breaking compat of the FAQ app by moving the
FAQ pages to a "Data" subspace of the FAQ space for the sole reason that
this is what AWM is doing now is not ok, because the reason is not good
enough. So, imo, since these reasons will really differ from app to app and
evaluation of what "good reason" means depends on the evaluator, we should
try to reach consensus by discussing it on a case by case basis, and not
have a single rule applied blindly.
I think I repeated myself 3 times, sorry you had to read through all of it
:D
Have fun,
Anca
What we decide to do?
Thanks,
Alex
_______________________________________________
devs mailing list
devs(a)xwiki.org
http://lists.xwiki.org/mailman/listinfo/devs
_______________________________________________
devs mailing list
devs(a)xwiki.org
http://lists.xwiki.org/mailman/listinfo/devs