Fix the NGINX configuration for GitLab Pages with Cache-Control headers

files/gitlab-cookbooks/gitlab/templates/default/nginx-gitlab-pages-http.conf.erb

@@ -70,6 +70,19 @@ server {
     proxy_set_header <%= header[0] %> <%= header[1] %>;
     <% end %>
 
+    # Prevent NGINX from caching pages in response to the pages `Cache-Control`
+    # header.
+    #
+    # Browsers already respect this directive and Pages can handle the request
+    # volume without help from NGINX.
+    #
+    # If this changes in the future, ensure `proxy_cache_key` is set to a value
+    # like `$scheme$host$request_uri`, as the default value does not take the
+    # Pages hostname into account, leading to incorrect responses being served.
+    #
+    # See https://gitlab.com/gitlab-org/gitlab-pages/issues/73
+    proxy_cache off;
+
     proxy_pass          http://<%= @pages_listen_proxy %>;
   }