[platform-update-dev] eclipse installation site types cleanup

[Dorian Birsan <birsan@xxxxxxxxxx>]

Currently, there are 3 types of local
installation sites:

1. product site - where eclipse plugins
are located. This is the regular eclipse installation directory and has
the following layout:
    <eclipse_product_site>\
           
                     
                 eclipse\
           
                     
                     
      .eclipseproduct
           
                     
                     
      features\
           
                     
                     
      plugins\
           
                     
                     
      startup.jar
           
                     
                     
      etc.
2. extension site - a site pointed to
by .link files. The eclipse product site contains a "links" directory
with one or more .link files as follows:
    <eclipse_product_site>\
           
                     
                 eclipse\
           
                     
                     
      .eclipseproduct
           
                     
                     
      features\
           
                     
                     
      plugins\
           
                     
                     
      startup.jar
           
                     
                     
      links\
           
                     
                     
                  <some_extension>.link
 

  The content of the link file
<some_extension>.link is
  path=[rw]
<eclipse_product_extension_site>
  (eg: path=/home/user/my_own_plugins)

  where the r(ead)/w(rite) flags
are optional, and the <eclipse_product_extension_site> is the full
path to an extension site, with the following layout:

  <eclipse_product_extension_site>\
           
                     
                 eclipse\
           
                     
                     
      .eclipseextension
           
                     
                     
      features\
         
                     
               plugins\


3. private site - created in the install
wizard when the user wants to install features into a new location.
   The site has the following
layout:
   <eclipse_private_site>
\
           
                     
     features \
           
                     
     plugins \
           
                     
     .eclipseUM


Then, in the UI (Manage Configuration),
someone can add an extension site, but no .link file is dropped into the
links folder, the info is maintained in the platform configuration file
(platform.xml) only. This appears to be a hybrid of product extension and
private site. 
Also,  private site cannot be added,
so if you update to a new driver, with a new configuration, you will have
to reinstall all the features already installed in a private site.
No site can be removed at all (they
can be disabled, though).
Unlike in 2.x, in 3.0 the configuration
data is maintained in a well-known location inside the configuration directory,
so new workspaces will inherit all the updates done while working on another
workspace.

My question is: do we still need "private"
sites? 

What I propose is this:
- have only two sites: product site
and product extension sites.
- a product extension site can be linked
with a .link file as before
- a product extension site can be added
in the UI (configuration manager)
- a product extension site can be created
by the install wizard
- a product extension site should be
removable via the configuration manager, as long as it was not linked by
a .link file (the links directory should be only managed by native installers)
- a product extension site can be unconfigured/disabled
- for consistency with the path specified
in a .link file, the add site dialog should allow selecting the actual
product extension (i.e. the folder containing the eclipse directory), as
opposed to having to select the eclipse folder itself as done now. Also,
when creating a site in the install wizard, instead of creating features
and plugins folders inside the selected location, create an eclipse parent
directory first.

Any suggestions/thoughts/concerns ?

-Dorian