following instances pattern for twemproxy integration

Author: swwolf

manifests/integrations/twemproxy.pp

@@ -11,7 +11,7 @@
 # Sample Usage:
 #
 #  class { 'datadog_agent::integrations::twemproxy' :
-#    servers => [
+#    instances => [
 #      {
 #        'host' => 'localhost',
 #        'port' => '22222',
@@ -24,11 +24,22 @@
 #  }
 #
 class datadog_agent::integrations::twemproxy(
-  $servers = [{'host' => 'localhost', 'port' => '22222'}]
+  $host = 'localhost',
+  $port = '22222',
+  $instances = [],
 ) inherits datadog_agent::params {
   include datadog_agent
 
-  validate_array($servers)
+  if !$instances and $host {
+    $_instances = [{
+      'host' => $host,
+      'port' => $port,
+    }]
+  } elsif !$instances{
+    $_instances = []
+  } else {
+    $_instances = $instances
+  }
 
   file { "${datadog_agent::params::conf_dir}/twemproxy.yaml":
     ensure  => file,

templates/agent-conf.d/twemproxy.yaml.erb

@@ -5,7 +5,7 @@
 init_config:
 
 instances:
-<% @servers.each do |server| -%>
+<% @instances.each do |server| -%>
   - host: <%= server['host'] %>
     port: <%= server['port'] %>
 <% end -%>