Puppet users - Oct 2007 - Setting variables in modules - order important?

Puppeteers,

For some reason I have to assign my variable before I include my class
for the assignment to ''take''.  I though the ordering was
immaterial.  Am
I doing something wrong (again) or is this a funny?

-----------------------

This works:

<0> sa_dewha@engpsr0000.intranetdev.barcapdev.com (0 jobs)
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/examples
  % cat setup.pp
$int_var = "Set in setup.pp example"
include ztest::setup

<0> sa_dewha@engpsr0000.intranetdev.barcapdev.com (0 jobs)
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/examples
  % ./test.sh; cat /var/tmp/test
++ pwd
+
MODULEDIR=/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztes
t/examples/../..
+ puppet --color=false -v --server=localhost 
+ --modulepath=/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules
+ /ztest/examples/../.. --libdir=/var/lib/puppet/plugins ./setup.pp
info: Autoloaded module ztest
notice: ztest::setup: Hello.  Testing.
notice: ztest::setup: int_var = Set in setup.pp example TEST FILE

int_var = Set in setup.pp example

-----------------------

This does not:
<0> sa_dewha@engpsr0000.intranetdev.barcapdev.com (0 jobs)
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/examples
  % cat setup.pp                
include ztest::setup
$int_var = "Set in setup.pp example"

<0> sa_dewha@engpsr0000.intranetdev.barcapdev.com (0 jobs)
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/examples
  % ./test.sh                   
++ pwd
+
MODULEDIR=/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztes
t/examples/../..
+ puppet --color=false -v --server=localhost 
+ --modulepath=/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules
+ /ztest/examples/../.. --libdir=/var/lib/puppet/plugins ./setup.pp
info: Autoloaded module ztest
notice: ztest::setup: Hello.  Testing.
notice: ztest::setup: int_var Failed to parse template ztest/test: Could not
find value for ''int_var''
at
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/examples
/../../ztest/manifests/init.pp:13

-----------------------

Support files:
<0> sa_dewha@engpsr0000.intranetdev.barcapdev.com (0 jobs)
 
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/manifest
s
  % cat init.pp

class ztest::setup {
    notice "Hello.  Testing."
    notice "int_var = $int_var"
    file { "/var/tmp/test":
        content => template("ztest/test")
    }
}

<0> sa_dewha@engpsr0000.intranetdev.barcapdev.com (0 jobs)
 
/users/unix/sa_dewha/SVNCheckOut/bootstrap/puppet/modules/ztest/template
s
  % cat test 
TEST FILE

int_var = <%= int_var %>

-----------------------

Derek

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On Oct 29, 2007, at 12:38 PM, <Derek.Whayman@barclayscapital.com> wrote:
> For some reason I have to assign my variable before I include my class
> for the assignment to ''take''.  I though the ordering was
> immaterial.  Am
> I doing something wrong (again) or is this a funny?
This is something I''ve actually fixed in the code, although I have  
not yet determined whether I''ll be able to include it in the next  
release, because it''s a huge chunk of work that might introduce more  
change than I''m comfortable with right now.

Basically, in the current release, ''include'' evaluates the
class
immediately.  What I''ve done is convert it to do lazy evaluation --  
it only evaluates the included class once the whole including class  
is evaluated.

This works by creating a ''class'' resource internally, one that
behaves almost exactly as a defined resource does.  Puppet was  
already iterating over these defined resources until all remaining  
resources were builtin (e.g., file, service); now it does the same  
thing with class resources.  This has a strange side effect in that  
you don''t have any guarantee of when a given class will be evaluated,  
other than that it''s after the including class is done being evaluated.

  --
  Tobacco stocks have taken a big tumble," says Jay Leno. "Phillip  
Morris
  fell 6 points.  They lost so much money they may have to lay off two
  senators."
  ---------------------------------------------------------------------
  Luke Kanies | http://reductivelabs.com | http://madstop.com

--On Monday, October 29, 2007 5:38 PM +0000 
Derek.Whayman@barclayscapital.com wrote:
> For some reason I have to assign my variable before I include my class
> for the assignment to ''take''.  I though the ordering was
immaterial.  Am
> I doing something wrong (again) or is this a funny?
There as been much discussion about variables and overriding variables and 
making variables order dependent.  In my opinion, this is a violation of 
what Puppet is trying to strive for, which is order independent, 
idempotency.

I personally prefer explicitly using declarations and overrides.  So in 
cases were we have a default "variable" and then are interested in
possibly
changing that "variable" in other classes, we simply use a definition
to
handle that variable and doing what it must with that variable and override 
that definition as needed.  This works great and I think it makes manifests 
easier to follow because you can see where a definition is being declared 
and where a definition is being overridden instead of trying to trace 
through chains of includes to see where things are being changed.