pin.pp

# pin.pp
# pin a release in apt, useful for unstable repositories

define apt::pin(
  $ensure     = present,
  $explanation = "${::caller_module_name}: ${name}",
  $order      = '',
  $packages   = '*',
  $priority   = 0,
  $release    = '',
  $origin     = '',
  $originator = '',
  $version    = '',
  $codename   = '',
  $component  = '',
  $label      = '',
) {

  include apt::params

  $preferences_d = $apt::params::preferences_d

  if $order != '' and !is_integer($order) {
    fail('Only integers are allowed in the apt::pin order param')
  }

  # Read the manpage 'apt_preferences', chapter 'The Effect of APT Preferences'
  # to understand the following logic
  if $packages != '*' { # specific form

    # keywords version, release and origin are mutually exclusive
    if ( $version != '' and ( $release != '' or $origin  != '' )) or 
       ( $release != '' and ( $version != '' or $origin  != '' )) or
       ( $origin  != '' and ( $version != '' or $release != '' )) {
    
      fail('keywords version, release and origin are mutually exclusive')

    }


    $pin = 

  } else { # specific form

  }

  if $release != '' {
    $pin = "release a=${release}"
  } elsif $origin != '' {
    $pin = "origin \"${origin}\""
  } elsif $originator != '' {
    $pin = "release o=${originator}"
  } elsif $version != '' {
    $pin = "version ${version}"
  } elsif $codename != '' {
    $pin = "release n=${codename}"
  } elsif $component != '' {
    $pin = "release c=${component}"
  } elsif $label != '' {
    $pin = "release l=${label}"
  } else {
    $pin = "release a=${name}"
  }

  $path = $order ? {
    ''      => "${preferences_d}/${name}.pref",
    default => "${preferences_d}/${order}-${name}.pref",
  }
  file { "${name}.pref":
    ensure  => $ensure,
    path    => $path,
    owner   => root,
    group   => root,
    mode    => '0644',
    content => template('apt/pin.pref.erb'),
  }
}