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Accepted
thinice
Asked: 2013-08-14 12:31:49 +0800 CST

Puppet - conditionally overriding a built-in default value

  • 772

Take this wrapper around ssh_authorized_key for example:

define sshauthkeys::helper ($user,$ensure='present') {


        ssh_authorized_key { "puppet: ${name2} ${user}":
          ensure => $ensure,
          type => $ssh_keys["${name2}"]["type"],
          key => $ssh_keys["${name2}"]["key"],
          user => "${user}"
        }
}

Let's say I wanted to introduce support of the 'target' parameter for that resource type, I'd do something like:

define sshauthkeys::helper ($user,$ensure='present', $target='') {

The problem is, if I want to use the sensible default from puppet derived from $user 's homedir - and override it on fringe cases, I lose the benefit of the work done to set the default in all of the other circumstances.

Is there a way to optionally override the value without having to write two functions?

Better description of the issue:

define sshauthkeys::helper ($user,$ensure='present', $target='') {

    ssh_authorized_key { "puppet: ${name2} ${user}":
      // etc etc...
      target = $target 
      // ^--- Here, I'm forcing it to '' - how do I use the puppet 
      // built-in derivation, and only override optionally?
    }

}

puppet

1 Answers

  1. Best Answer

    In this case, setting target => undef is the same thing as not specifying it at all, so you can write your wrapper like this:

    define sshauthkeys::helper ($user,
  $ensure='present',
  $target=undef
) {
    ssh_authorized_key { "puppet: ${name2} ${user}":
      ensure => $ensure,
      target => $target,
      type   => $ssh_keys["${name2}"]["type"],
      key    => $ssh_keys["${name2}"]["key"],
      user   => "${user}"
    }
}
    • 5