Allow puppet to configure Gerrit's download protocols

Gerrit 2.11 has a download[1] option that allows customization
of download commands and schemes.  Allow puppet to configure
this so we can customize it.

[1] https://review.openstack.org/Documentation/config-gerrit.html#download

Change-Id: Ia6a3a28cce62b6bd1570fd0ab5b1224fc35d8284

manifests/init.pp

@@ -118,6 +118,15 @@
 #     Set this to false to disable drafts feature
 #   receive_max_object_size_limit
 #     Maximum allowed Git object size that 'receive-pack' will accept.
+#   download:
+#     The allowed download commands and schemes.  The data structor for this
+#     should be a hash with keys and array of values (i.e. {key => [values]})
+#     Example:
+#       download      => {
+#           'command' => ['checkout', 'cherry_pick', 'pull', 'format_patch'],
+#           'scheme'  => ['ssh', 'anon_http', 'anon_git'],
+#           'archive' => ['tar', 'tbz2', 'tgz', 'txz'],
+#       },
 # TODO: make more gerrit options configurable here
 #
 class gerrit(
@@ -212,6 +221,7 @@ class gerrit(
   $receive_max_object_size_limit = '',
   $cache_diff_timeout = '',
   $cache_diff_intraline_timeout = '',
+  $download = {},
 ) {
   include ::httpd
 
@@ -394,6 +404,7 @@ class gerrit(
   # - $receive_max_object_size_limit
   # - $cache_diff_timeout
   # - $cache_diff_intraline_timeout
+  # - $download
 
   file { '/home/gerrit2/review_site/etc/gerrit.config':
     ensure  => present,

templates/gerrit.config.erb

@@ -180,6 +180,14 @@
 	threads = <%= @index_threads %>
 <% end -%>
 <% end -%>
+<% unless @download.empty? -%>
+[download]
+  <% @download.each do |key, item| -%>
+    <% item.each do |value| -%>
+      <%= key %> = <%= value %>
+    <% end -%>
+  <% end -%>
+<% end -%>
 [groups]
         newGroupsVisibleToAll = <%= @new_groups_visible_to_all %>
 [mimetype "image/*"]