copy: templates

[Will Lowe]

I'm using cfengine 2.x (right now 2.0.4, but I don't mind upgrading)
under Debian woody.  Let's say I have several variables set in my
cfagent program named $cfgroot, $site, $type, and $host, with the
obvious meanings.

I'd like to do something like this:

copy:

        $cfgroot/$host/etc/resolv.conf dest=/etc/resolv.conf recurse=inf
# if it exists, otherwise try:
        $cfgroot/$type/etc/resolv.conf dest=/etc/resolv.conf recurse=inf
# if it exists, otherwise try:
        $cfgroot/$site/etc/resolv.conf dest=/etc/resolv.conf recurse=inf
# if it exists, otherwise try:
        $cfgroot/default/etc/resolv.conf dest=/etc/resolv.conf recurse=inf

... in other words, I'd like to be able to maintain (possibly partial)
sets of configs for each of $site, $type, $host, and a default set,
and have cfengine automatically find the "most specific" action to
apply.

An additonal catch is that I'd like to do it for *every* *single* copy
statement anywhere in the cfagent config (find the most specific
resolv.conf, the most specific set of apache configs, the most
specific /etc/nsswitch.conf, etc.) -- a generic templating system.

Using groups/classes might be possible:

sitefoo.farma:
        copy resolv.conf.1234

sitefoo.!farmb.farmc.!sitebar:
        copy resolv.conf.4321

siteBaz.farmF:
        copy resolv.conf.0987

... but with 15 farms, 1000 servers, and 10 sites, the number of
possibly needed rules becomes insane.  It'd be a lot simpler if
cfengine could find the "best match" somehow on its own ... any ideas?

-- 
                                        thanks,
                
                                        Will