Creating user with random password (only once)

Hi,

I want to create a user with a random password. Is there a way to only
execute the manifest once when the user does not exist but not once
the user is created?

I know how to create a random password and can use generate to execute
this function (or make it a custom fact provided I get this fact
executed).

So far I call an add_user method define in a users module out of my
base class. Here is the code:

  include users

  users::add_user { 'testuser':
    name     => 'testuser',
    uid      => '777',
    password => generate('/usr/local/bin/new_hash'),
    shell    => '/bin/csh',
    groups   => 'testuser',
  }

But alas this will get executed every time the client runs since the
password will have changed due to the new generate call.

One work-around I could think of is to create the user on the client
(FreeBSD) using an exec calling the makepassword and pw command.

Then I could check for existance of the user in the masterpasswd file
with an unless check.

But I much prefer do this with Puppet natively.

Any suggestions will be greatly appreciated.

Werner