Installing a puppet module from a manifest script

I'm using puppet to provision a vagrant (ubuntu based) virtual machine. In my script I need to:

sudo apt-get build-dep python-lxml

I know I can install the apt puppet module so I can use:

apt::builddep { 'python-lxml': }

But I can't find any reference about installing a module from the script and how to include/require it. Seems to me that the puppet docs refer only to installing from the command line puppet tool

I also tried doing something like:

define build_dep($pkgname){
    exec {
    "builddepend_$pkgname":
    commmand => "sudo apt-get build-dep $pkgname";
    }
}
build_dep{
    "python-imaging":
    pkgname => "python-imaging";

    "python-lxml":
    pkgname => "python-lxml";
}

But puppet exited with an error on this. And also:

exec{"install apt module":

    command => "puppet module install puppetlabs/apt"
}

class { 'apt':
        require => Exec["install apt module"]}
include apt

apt::builddep { 'python-imaging':
 }

but got could not find declared class apt at..

any ideas? directions? I know I'm missing something obvious but can't figure this out.

EDIT: If I pre-install (with puppet module install from the commandline) the apt:builddep works fine. But I need puppet to handle the module downloading and installation. Some of the other work arounds also work for the basic use case but won't answer my main question.

Solution

I ran into this problem as well. The trick is to download the modules using a vagrant shell command before the puppet provisioner runs.

config.vm.provision :shell do |shell|
  shell.inline = "mkdir -p /etc/puppet/modules;
                  puppet module install puppetlabs/nodejs;
                  puppet module install puppetlabs/apache"
end

config.vm.provision :puppet do |puppet|
  puppet.manifests_path = "puppet/manifests"
  puppet.manifest_file = "site.pp"
end

Order is important here, and since the puppet provisioner hasn't run the folder /etc/puppet/modules does not exist yet.

The reason I decided, like alonisser, to install the modules using the puppet module tool instead of using a module folder with the vagrant puppet provisioner was because I didn't want to have to download all of the dependencies of the modules I was going to use and store all of those modules in my source control. Running these two commands results in 5 dependencies that would otherwise sit in my git repository taking up space.