Proposal: Rework the current xdg-utils. (with implementation details)

[洪任諭]

Hello,
I'm the lead developer of LXDE. < http://lxde.org/ >
I have some thoughts regarding to some limitations of current xdg-utils.
Here are some proposals to rework it and make it totally extensible.

Limitations of current implementation:
1. It only recognize gnome, xfce, and kde and is far from being truely
cross-desktop.
2. Authors of new desktop environment need to hack xdg-utils to support their
desktop environments, and hope someday Portland project will include
their patch.
3. The number of desktop environments is still increasing, and in this way,
xdg-utils will finally become very complicated and full of dirty hacks.
4. Even if I only get xfce installed on my distro, xdg-utils still
needs to check all the others.
5. Portland project is hard to participate. I sent mails to the
mailing list, and they just got ignored.

Easy and backward-compatible solution for all the preceding problems -
Let desktop environments install their own scripts.

Implementation Details (Advantages and disadvantages are listed later
in this mail)
Taking xdg-utils for example, it should work like this:

Looking for scripts in "/usr/share/xdg-utils/xdg-open.d" (or other
places are ok).
Scripts from various desktop environments can be installed there.
50-gnome
50-kde
60-kde3
50-xfce
99-generic
The numbers means "priority". The generic one, of course, has the
lowest priority.
This is common practice on UNIX systems.
Then, run the scripts installed by various desktop environments one by one.
Every script in that dir checks if current desktop session is theirs.
If it is, the script opens the file/url with their own mechanism, and returns 0.
Otherwise, it returns an error codes.
Once failed, the next script with lower priority will be tried.

Advantages:
1. Highly extensible.
2. Won't break any compatibility with current implementation.
3. Easy to maintain. (The scripts are all maintained by authors from
respective desktop environments, not you guys from Portland)
It's impossible for Portland developers to maintain hacks for all kinds of
desktop environment and constantly fix them for future versions of those
desktop environment. It's quite inefficient and hard to get things right.
4. Don't need to hard code detection for all kinds of desktop
environments in one
very large and complicated xdg-* script.
5. Only the desktop environments *really* installed on the system are
checked since those scripts are provided by the DEs themselves. So you'll
never always try to find gnome or kde, like the current xdg-utils,
even if they are not installed.

Disadvantages:
1. The performance is slightly worse. (Since this command won't be
executed continuously in a large loop, it's not a real issue.)
2. Potential conflicts between scripts installed by various desktops.
(This is not possible if those scripts are well-written)

For xdg-mime and others, the same method can be used.

This can solve all of the problems in current implementation.
Any comments? Is it possible to get this new design into Portland xdg-utils?

Thank you all in advance.