apt:🔑 Be explicit about the keyserver.

The behaviour of passing down undef through multiple layers gets fuzzy
so for now be explicit about the keyserver.

Once Puppet 4 is out and this behaviour has been crystallised and tested
we can revisit it.

manifests/key.pp

@@ -42,9 +42,7 @@
 #   _default_: +undef+
 #
 #   The keyserver from where to fetch our GPG key. It can either be a domain
-#   name or url. It defaults to
-#   undef which results in apt_key's default keyserver being used,
-#   currently +keyserver.ubuntu.com+.
+#   name or url. It defaults to +keyserver.ubuntu.com+.
 #
 # [*options*]
 #   _default_: +undef+
@@ -55,7 +53,7 @@ define apt::key (
   $ensure  = present,
   $content = undef,
   $source  = undef,
-  $server  = undef,
+  $server  = $::apt::keyserver,
   $options = undef,
 ) {
 

manifests/params.pp

@@ -11,6 +11,7 @@ class apt::params {
   $conf_d         = "${root}/apt.conf.d"
   $preferences    = "${root}/preferences"
   $preferences_d  = "${root}/preferences.d"
+  $keyserver      = 'keyserver.ubuntu.com'
 
   if $::osfamily != 'Debian' {
     fail('This module only works on Debian or derivatives like Ubuntu')
@@ -52,7 +53,7 @@ class apt::params {
   }
 
   $source_key_defaults = {
-    'server'  => $default_keyserver,
+    'server'  => $keyserver,
     'options' => undef,
     'content' => undef,
     'source'  => undef,