Advice on modelling some behaviour
Ross.Mc...@sophos.com
Having trouble trying to model some behaviour in puppet and would
appreciate some suggestions on how I could achieve it.
I'm trying to write out multiple similar items to a file, think shares in
smb.conf to take one example I'll use throughout (although there's other
places I need to do this aswell).
So the end result I'd like is roughly, to say:
node my-smb-server {
smb_share{ "myshare":
path => "/path/to/share",
users=> "user1,user2,user3"
}
}
An extra caveat is that I'd like to be able to define these shares in a
few places. So say, some shares under a node definition and some shares in
an included class (e.g. all servers have one share, but only some servers
have another share).
Then in my ruby template, I'd guess I'd loop over some list, writing out
the config as I go.
So the problems I'm having are:
The naive solutions results in me trying to manage the same file multiple
times, which obviously isn't possible
Trying to bring them all together by, in my resource definition, importing
a class and assigning to a list in that class but fails because 1) I dont
think the +> syntax works for lists and 2) you cant assign to variables in
another class.
I've got a nasty feeling I'm missing a really obvious nice way to do this,
but I just cant get my head round it, hence any advice would be
appreciated. It's really easy for services like apache that allow you to
do "include /etc/.../conf.d" as you can just stick in seperate files but
when you cant I get stuck :)
-ross
--
Ross McKerchar
Systems Analyst, Sophos
Tel: 01235 559933
Web: http://www.sophos.com
Sophos - security and control
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Al @ Lab42
file or line:
http://git.black.co.at/?p=module-common;a=tree;f=manifests/defines;hb=HEAD
Al
Ross.McKerc...@sophos.com ha scritto:
Luke Kanies
>
> Hi Guys,
>
> Having trouble trying to model some behaviour in puppet and would
> appreciate some suggestions on how I could achieve it.
>
> I'm trying to write out multiple similar items to a file, think
> shares in
> smb.conf to take one example I'll use throughout (although there's
> other
> places I need to do this aswell).
>
> So the end result I'd like is roughly, to say:
>
> node my-smb-server {
> smb_share{ "myshare":
> path => "/path/to/share",
> users=> "user1,user2,user3"
> }
> }
>
> An extra caveat is that I'd like to be able to define these shares
> in a
> few places. So say, some shares under a node definition and some
> shares in
> an included class (e.g. all servers have one share, but only some
> servers
> have another share).
>
> Then in my ruby template, I'd guess I'd loop over some list, writing
> out
> the config as I go.
This is a relatively common problem, and people who don't write native
resource types use a kind of file snippet system -- make a definition
that writes the appropriate samba config for each share to something
like /etc/samba.d, then have an exec that combines these into the
correct configuration file, using 'subscribe' to trigger the exec.
Make sense?
Isn't there one of these published somewhere?
--
The most likely way for the world to be destroyed, most experts agree,
is by accident. That's where we come in; we're computer professionals.
We cause accidents. --Nathaniel Borenstein
---------------------------------------------------------------------
Luke Kanies | http://reductivelabs.com | http://madstop.com
Peter Meier
> This is a relatively common problem, and people who don't write native
> resource types use a kind of file snippet system -- make a definition
> that writes the appropriate samba config for each share to something
> like /etc/samba.d, then have an exec that combines these into the
> correct configuration file, using 'subscribe' to trigger the exec.
>
> Make sense?
>
> Isn't there one of these published somewhere?
DavidS' common module [1] has something like that integrated.
[1] http://git.black.co.at/?p=module-common;a=summary
greets pete
Ross.Mc...@sophos.com
> On Jun 27, 2008, at 10:32 AM, Ross.Mc...@sophos.com wrote:
>
> > Having trouble trying to model some behaviour in puppet and would
> > appreciate some suggestions on how I could achieve it.
> >
> > I'm trying to write out multiple similar items to a file, think
> > shares in
> > smb.conf to take one example I'll use throughout (although there's
> > other
> > places I need to do this aswell).
> >
> > <snip>
> >
> > Then in my ruby template, I'd guess I'd loop over some list, writing
> > out
> > the config as I go.
>
> This is a relatively common problem, and people who don't write native
> resource types use a kind of file snippet system -- make a definition
> that writes the appropriate samba config for each share to something
> like /etc/samba.d, then have an exec that combines these into the
> correct configuration file, using 'subscribe' to trigger the exec.
Thanks for all the help.
I've checked out David's common module: it can definitely achieve some
(but not all) of what I'm looking for.
The "natural" way that I first tried to model this kind of behaviour is as
follows (please forgive my slightly wacky puppet-pseudocode, hopefully
you'll get the idea):
class a {
$settings = [a,b]
file {"/etc/file.conf": content => template('erb file with
content: settings.join(",")') #Contents of file.conf will be out a,b
}
class b inherits a {
$settings +> [c,d] #Contents of file.conf will be out a,b,c,d
}
Of course this doesn't work - lists are immutable and it appears you
actually have to explicitly duplicate the file definition in all
subclasses to use the assoicated overridden variable.
Is this, or something similar (the above is obv. limited to each "setting"
only having one variable), a sensible feature request? It seems to be
quite a natural thing to be able to do with resorting to any exec-based
black magic.
regards,