Allow to specify a custom network server hostname

When sending metrics to multiple services on distinct ports on the same
node, in order to avoid conflicts we need to allow overriding the server
hostname on a per resource basis.

Example use case:

```puppet
class { 'collectd::plugin::network':
  servers => {
    'collectd' => {
      hostname => 'remote.example.com',
      port     => 25826,
    },
    'influxdb' => {
      hostname => 'remote.example.com',
      port     => 25827,
    },
  },
}
```

REFERENCE.md

@@ -8812,6 +8812,7 @@ The collectd::plugin::network::server class.
 
 The following parameters are available in the `collectd::plugin::network::server` defined type:
 
+* [`hostname`](#-collectd--plugin--network--server--hostname)
 * [`ensure`](#-collectd--plugin--network--server--ensure)
 * [`username`](#-collectd--plugin--network--server--username)
 * [`password`](#-collectd--plugin--network--server--password)
@@ -8821,6 +8822,14 @@ The following parameters are available in the `collectd::plugin::network::server
 * [`forward`](#-collectd--plugin--network--server--forward)
 * [`resolveinterval`](#-collectd--plugin--network--server--resolveinterval)
 
+##### <a name="-collectd--plugin--network--server--hostname"></a>`hostname`
+
+Data type: `String[1]`
+
+The hostname of the server to connect to
+
+Default value: `$name`
+
 ##### <a name="-collectd--plugin--network--server--ensure"></a>`ensure`
 
 Data type: `Enum['present', 'absent']`

manifests/plugin/network/server.pp

@@ -1,6 +1,8 @@
 #
+# @param hostname The hostname of the server to connect to
 define collectd::plugin::network::server (
   Enum['present', 'absent'] $ensure                         = 'present',
+  String[1] $hostname                                       = $name,
   Optional[String] $username                                = undef,
   Optional[String] $password                                = undef,
   Optional[Stdlib::Port] $port                              = undef,

spec/defines/collectd_plugin_network_server_spec.rb

@@ -14,6 +14,7 @@
         let(:title) { 'node1' }
         let :params do
           {
+            hostname: 'node1.example.com',
             port: 1234,
             interface: 'eth0',
             securitylevel: 'Encrypt',
@@ -26,7 +27,7 @@
           is_expected.to contain_file("#{options[:plugin_conf_dir]}/network-server-node1.conf").with(
             ensure: 'present',
             path: "#{options[:plugin_conf_dir]}/network-server-node1.conf",
-            content: "<Plugin network>\n  <Server \"node1\" \"1234\">\n    SecurityLevel \"Encrypt\"\n    Username \"foo\"\n    Password \"bar\"\n    Interface \"eth0\"\n\n  </Server>\n</Plugin>\n"
+            content: "<Plugin network>\n  <Server \"node1.example.com\" \"1234\">\n    SecurityLevel \"Encrypt\"\n    Username \"foo\"\n    Password \"bar\"\n    Interface \"eth0\"\n\n  </Server>\n</Plugin>\n"
           )
         end
       end

templates/plugin/network/server.conf.erb

@@ -1,6 +1,6 @@
 <Plugin network>
 <% if scope.lookupvar('collectd::collectd_version_real') and (scope.function_versioncmp([scope.lookupvar('collectd::collectd_version_real'), '4.7']) >= 0) -%>
-  <Server "<%= @name %>" "<%= @port %>">
+  <Server "<%= @hostname %>" "<%= @port %>">
 <% if @securitylevel -%>
     SecurityLevel "<%= @securitylevel %>"
 <% end -%>