[osgeo4w-dev] Progress Update

[Frank Warmerdam]

Folks,

Jeff McKenna, Yewondwossen Assefa and I met Thursday at the DMSG offices
to discuss OSGeo4W, the main topic being what installer technology to utilize
going forward.

Jeff and Assefa demonstrated progress with the MS4W "net installer" using
NSIS which worked quite smoothly.  But they explained that it was not so
clear to them how to accomplish some of the other things handled by the
cygwin style installer.  In particular, it was challenging to have a dynamic
installer that understand what updates had become available since an earlier
install.

We reviewed the Cygwin derived installer and agreed that the approach as it
stands is to complex and technical for many of the "Getting Started with FOSS"
users we want to support.  The main tree list is intimidating for a starting
user, and several of the other preliminary steps (selecting a mirror,
one user vs. all users) are mostly just confusing.

The decision was to engineer an "express install" path into the cygwin derived
installer.  One that would have the following sequence of steps:

1) User selects Express vs. Advanced install.  Advanced would take them into
the existing set of steps, likely with the mirror selection step removed.  The
rest assumes express.

2) The user is presented with a short list (8-12) of major packages they can
install.  This would include things like MapServer, Apache, QGIS, GRASS.  Each
item would have a checkbox to select it.  If it is already installed the
checkbox would be shown checked.

3) If Apache is selected a custom page would be presented to select the port
number, and indicate if it should be installed as a service.

4) The normal progress monitor style page as things are being installed.

5) The completed page.

A few other notes:

  * We are inclined to drop the option of creating a desktop icon and menu
    entry believing that these are essentially always useful, and can be easily
    removed if not needed.

  * The express install would operate "For All Users".  There is some question
    what happens if the installing user does not have administrative access.

  * We believe we need a small .exe that can be used from post-install .bat
    files to add menu items and new desktop icons.

  * For the express install, we would take tend to be generation in selecting
    fine grained packages that are associated.  So, for instance, installing
    GRASS would automatically trigger installing GDAL, but we might also
    throw in optional GDAL plugins.  Installing MapServer might also result
    in some MapServer applications being installed that aren't too large.

There was also substantial discussion on whether we pick a stable version of
a package and stick to it (for a year) or whether we have a way of offering
new releases.  It is felt that OSGeo4W will be substantially hampered if it
has no option to let people install new releases of our major packages when
these releases occur and that in fact it is desirable to offer a way to
delivery "development" versions of some packages.

For instance, if we pick MapServer 5.0.0 as "our stable rev" for OSGeo4W 2008
what do we do as new releases come out through 2008? For point releases
the answer is fairly clearly that we upgrade to the point releases.  So
5.0.2, 5.0.3, etc.  No problem as these are generally very careful to remain
compatible with the major release they originate from.

But we hope for a 5.2 MapServer release in the spring or early summer.  Will
this remain unavailable to OSGeo4W users till 2009?  We hesitate to just
treat this as a direct upgrade since there is a fairly high probability that
it will at least subtly break applications fairly tightly tied to MapServer
such as Chameleon as well as applications that include complex map files.

It was decided that we will explore how to off the ability for a user to
install these newer revisions through the Advanced Install using either the
"Experimental" version support in the installer or some related means.  A
way for the user to explicitly select to install the newer version.  The idea
being that it will not be automatically upgraded and the less sophisticated
user will get the safe experience.  But someone who wants to will have options
to install newer versions.

Likewise we would like to explore ways of providing frequently rebuilt
development versions.

Significant additional thinking will need to go into how to accomplish this
without degrading the safety of the standard install.

I have agreed to try and develop the express install mechanism in the next
week or two.  Jeff and Assefa will launch into "clean" packaging most of
the MapServer and web mapping applications currently in MS4W for OSGeo4W.

I would add that since our meeting I have been seriously thinking about
how deliver the FWTools experience (bleeding edge dev versions of GDAL,
PROJ and MapServer) via OSGeo4W.  If that seems practical, would love to
be able to end production of the FWTools win32 releases to focus all my
energy on OSGeo4W for that role.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org