Forum: Cfengine Help
Subject: Re: bundlesequence and module protocol
Author: sauer
Link to topic: https://cfengine.com/forum/read.php?3,21208,21212#msg-21212
elwood Wrote:
-------------------------------------------------------
> Why is commands so far down on the list? Given the module protocol it would
> seem that commands is one of the few types that needs to be executed as soon
> as possible.
...
> The workaround I have to use right now is have my modules emit a special
> "module_name_has_run" class to use as a guard for anything that uses a
> variable that is generated by a module. This works, but yuch.
It might be worth looking into the usemodule function. Same module protocol,
but applies in the classes: section. Bonus points: sets the class specified
when execution is finished, freeing you from having to set that class with the
module protocol. That way you can have commands be later on for things which
depend on the other stuff, but have your stuff which use the module protocol
run early. This might be about the only "have cake and eat it too" thing in
Cfengine, actually. :) The only difference is that this one requires the
modules to be located under $WORKDIR/modules, which isn't a huge deal. At
worst, you write a thin wrapper and put it in that directory.
classes:
program_is_done expression => usemodule("awesomemodule", "args")
The scoping thing can also be addressed using methods if you're not excited
about having to "and" a zillion classes in a bunch of places. Just do
something like
methods:
dependencyone&dependencytwo::
"thisstringisirrelevant" usebundle => superduperbundle("$arg", "$otherarg");
and put all the files / commands / whatever promises into superduperbundle. I
think I use that for scope consolidation more than any other more legitimate
purpose.
FWIW, I'm doing roughtly what you are; integrating cfengine into a very large
existing environment with a lot of (often ill-conceived) legacy junk, slowly
migrating legacy processes into native Cfengine. It works fine, but takes some
doing to wrap your head around it enough to creatively shoehorn everything into
what's actually a pretty well thought-out system. And it doesn't require
learning an otherwise worthless language like Ruby. ;)
_______________________________________________
Help-cfengine mailing list
Help-cfengine@cfengine.org
https://cfengine.org/mailman/listinfo/help-cfengine
