Support Community Modules Collections Safely

Sites may wish to include community based packages use the module system. However not all users at a site want to know about a specialized group of modules. Also the community may provide bugg modules. There is a way to protect your regular users from the different collections.

The goals of this method are the following:

1. All users just see a gateway module for each collection.

2. The modules in the collection do not show up in avail or spider for regular users.

3. To see the collection a user must load the gateway module.

4. After loading the gateway module then will “module avail” and “module spider” show the collection.

5. Optionally sites can provide a spider cache for each separate collection if it is large.

Suppose you have a group that provides a collection of biology packages. Lets call the gateway module “biology”. Here is a prototype module where you are going provide a spider cache for the collection:

if ( mode() ~= "spider" ) then
   prepend_path("MODULEPATH",    "/path/to/biology/modulefiles")
end

-- Only do the following if you are providing a spider cache for
-- this collection
prepend_path("LMOD_RC",         "/path/to/biology/lmodrc.lua")

If you are providing a spider cache for the collection then your site will need a lmodrc.lua file for the collection:

scDescriptT = {
  {
    ["dir"]      =  "/path/to/biology/spider_cache",
    ["timestamp"] = "/path/to/biology/timestamp",
  },
}

Finally you need to build the spider cache. This can be done with update_lmod_system_cache_files:

% $LMOD_DIR/update_lmod_system_cache_files -d /path/to/biology/spider_cache -t /path/to/biology/timestamp /path/to/modulefiles

This command to update the cache files must be done every time there are new modulefiles added to the collection and typically has to be run with a privileged account or one that can write to the directories. It may be best if the cache file is regenerated automatically (say every 30 minutes) to keep it up-to-date.

Also it is important that all the paths match between the gateway modulefile, the lmodrc.lua file and command line above.