Added list_pages method to avoid loading all wiki pages content

Inside a wiki, when we show the sidebar or browse to the `pages`,
all page contents are retrieved from Gitaly and that is a waste
of resources, since no content from that pages are going to be
showed.

This MR introduces the method `ProjectWiki#list_pages`,
which uses new wiki_list_pages RPC call to retrieve
pages without content

Also in the `WikisController` we're using the method to show
pages in the sidebar and also on the `pages` page.

1 files changed, 22 insertions, 1 deletions

diff --git a/lib/gitlab/gitaly_client/wiki_service.rb b/lib/gitlab/gitaly_client/wiki_service.rb
index e036cdcd800..ce9faad825c 100644
--- a/lib/gitlab/gitaly_client/wiki_service.rb
+++ b/lib/gitlab/gitaly_client/wiki_service.rb
@@ -87,7 +87,27 @@ module Gitlab
         wiki_page_from_iterator(response)
       end
 
-      def get_all_pages(limit: 0, sort: nil, direction_desc: false)
+      def list_all_pages(limit: 0, sort: nil, direction_desc: false)
+        sort_value = Gitaly::WikiListPagesRequest::SortBy.resolve(sort.to_s.upcase.to_sym)
+
+        params = { repository: @gitaly_repo, limit: limit, direction_desc: direction_desc }
+        params[:sort] = sort_value if sort_value
+
+        request = Gitaly::WikiListPagesRequest.new(params)
+        stream = GitalyClient.call(@repository.storage, :wiki_service, :wiki_list_pages, request, timeout: GitalyClient.medium_timeout)
+        stream.each_with_object([]) do |message, pages|
+          page = message.page
+
+          next unless page
+
+          wiki_page = GitalyClient::WikiPage.new(page.to_h)
+          version = new_wiki_page_version(page.version)
+
+          pages << [wiki_page, version]
+        end
+      end
+
+      def load_all_pages(limit: 0, sort: nil, direction_desc: false)
         sort_value = Gitaly::WikiGetAllPagesRequest::SortBy.resolve(sort.to_s.upcase.to_sym)
 
         params = { repository: @gitaly_repo, limit: limit, direction_desc: direction_desc }
@@ -95,6 +115,7 @@ module Gitlab
 
         request = Gitaly::WikiGetAllPagesRequest.new(params)
         response = GitalyClient.call(@repository.storage, :wiki_service, :wiki_get_all_pages, request, timeout: GitalyClient.medium_timeout)
+
         pages = []
 
         loop do