Re: [ZMapServer-Developers] Re: [ZMapServer-Users] 0.7.6 release and update

[Sean G. <sgi...@fr...>]

On Aug 17, 2004, at 1:25 AM, Silke Reimer wrote:

> Hi Sean,
>
> On Mon, Aug 16, 2004 at 10:48:40AM -0600, Sean Gillies wrote:
>> Hi,
>>
>> I've made a new release of ZMapServer which enables it to work
>> with MapServer 4.2 and take advantage of major improvements in
>> MapServer 4.2.2.  There are no new features (other than improved
>> stability) in this release.
>>
>> Future work on ZMapServer is going to involve major refactoring.
>> I have spent the past months learning more about MapServer, and
>> about programming mapscript apps using other frameworks like
>> Twisted and mod_python.  I plan to factor out of ZMapServer
>> everything that can be useful to non-Zope applications and call
>> this package 'Python Cartographic Library' or something like that.
>> It will be a more Python-friendly facade in front of the awkward
>> MapServer mapscript module and will, in the future, rely more or
>> less upon MapServer depending on the future development of the
>> MapServer software.  The future ZMapServer product will then
>> contain only Zope-specific code and will draw upon the new package
>> for cartographic capabilities.
>
> These are great news for me. I often thought about using the
> ZMapServer for my projects and I always had the problem that I would
> like to use my applications within the Zope as well as without Zope
> mainly depending on whether a user management is needed or not. It
> has never been very urgent for me so I didn't find the time to
> seperate the code into Zope and non-Zope specific parts.
>
>>
>> If you are at all interested in contributing to discussion or work
>> on a new and improved Python cartographic/MapServer module, please
>> email me.  I am also on the #mapserver channel on freenode.net
>> and happy to discuss it in that forum.
>
> At the moment we are considering of developing such a
> cartographic/MapServer module that you are talking about (as Free
> Software of course). So it will be possible that I can and will
> contribute some parts to it.  Do you already have some concrete
> plans how you want to set up the architecture?
>
> Greetings,
>
> 	Silke
>

Hi Silke,

Thanks for the feedback.  Concrete plans?  No class diagrams yet if
that's what you mean, but I can tell you the general plan so far by
comparison to MapServer -- since I still intend to use MapServer for
much of the low-level stuff, replacing it as necessary with new code.

- Focus on Layers: good bye to the MapServer map/layer/class hierarchy.
   As with WMS, complicated maps will be formed from a tree of Layers.
   Have you used the elementtree module for XML?  I think this could
   be a good model for a tree of mapping layers.  Any layer will have
   full mapping capbility: drawing, querying, etc.

- Separation of data and presentation: pull style directives out of
   layer/class and instead use some sort of stylesheet.  Maybe CSS-like,
   maybe more like OGC SLD?

Major conceptual change from MapServer is that instead of loading a
mapfile from disk, parsing map file, parsing expressions, and drawing
an output map we will start with persistable Python objects that are
factories for MapServer objects.  I'm no longer interested in improving
the fundamental mapscript objects, we'll just use them as transient
things for drawing and querying and then throw them away just as
the CGI mapserver applications do.

cheers,
Sean

--
Sean Gillies
sgillies at frii dot com
http://users.frii.com/sgillies