Re: ZeroInstall & Package systems [Was: Re: Dock padding_pixels suggestion]

On Tue, 10 Jul 2007 21:05:58 +0000, Tuomo Valkonen wrote:
> On 2007-07-10, Thomas Leonard <[email protected]> wrote:
[...]
> No, I was not even aware of zeroinstall, and from quick glance, can  
> spot a few real or potential problems:
> 
>   * Package creation seems to be a choice between WIMPshit and XMLshit, 
>     judging from the packaging tutorial. No thanks.

The third option is 0publish (non-GUI):

 http://0install.net/0publish.html

On the other hand, you've already written a download page in HTML, so how
much worse can XML be?

>   * How about dependencies? That's where these decentralised 
>     packaging systems tend to fail compared to distros.

ROX-Filer doesn't list any (it just assumes everyone has GTK), but if you
want some examples that do, try:

$ 0alias svn http://0install.net/2007/3rd-party/Subversion.xml

That will also download up to 11 other libraries, although it might
default to fewer if you're on a Debian-type system and you have some of
them already, and a new enough version of 0alias. You can choose whether
to use the distribution's packages or download the Zero Install ones, in
that case.

Another example of dependencies is if you compile ROX-Filer from source:

$ 0alias 0compile http://0install.net/2006/interfaces/0compile.xml
$ 0compile setup http://rox.sourceforge.net/2005/interfaces/ROX-Filer

That will download old versions of the GTK header files to compile
against, so that the resulting binary works everywhere, not just on new
systems.

> On the positive side, it seems to use URLs and local aliases
> (that apply to binaries too!), instead of relying on a fully 
> centralised naming scheme. It's not fully decentralised, though,
> because DNS is centralised.

True, although you can use IP addresses (same problem ultimately, though).

> I've actually been thinking lately a bit about decentralised
> packaging systems, and have been meaning to write about it
> in the non-blog in more detail. In summary, the key 
> features/principles would, however be:
> 
>   * Uses application directories (with relocatable binaries, so
>     can be installed anywhere). That's absolutely necessary for
>     decentralised packaging.

Of course.

[ Capabilities ]

We don't really support those at the moment. Maybe when there are more
packages...

>   * The package system would be integrated with the build system.
>     Presently there's a _lot_ of redudancy between distributions'
>     package descriptions and autocrap. But a decent build system
>     would include all the dependency information in an easily
>     accessible format [1].

Certainly. If you can download libraries on demand then you don't need to
test to find out what you've got; you just ask for what you want.


-- 
Dr Thomas Leonard		http://rox.sourceforge.net
GPG: 9242 9807 C985 3C07 44A6  8B9A AE07 8280 59A5 3CC1