Merge branch 'sh-optimize-read-only-check' into 'master'

Optimize read-only middleware so that it does not consume as much CPU

Closes #40185 and gitlab-com/infrastructure#3240

See merge request gitlab-org/gitlab-ce!15504

(cherry picked from commit 6c3398165469de7890cd7881b175858f7c6be8e5)

3c52e2f0 Optimize read-only middleware so that it does not consume as much CPU
cba68d33 use `Gitlab::Routing.url_helpers` instead of `Rails.application.routes.url_helpers`
91075c82 check for `read_only?` first before seeing if request is disallowed
aeb2f49f Revert "check for `read_only?` first before seeing if request is disallowed"

1 files changed, 7 insertions, 1 deletions

diff --git a/lib/gitlab/middleware/read_only.rb b/lib/gitlab/middleware/read_only.rb
index 5e4932e4e57..c26656704d7 100644
--- a/lib/gitlab/middleware/read_only.rb
+++ b/lib/gitlab/middleware/read_only.rb
@@ -58,7 +58,7 @@ module Gitlab
       end
 
       def last_visited_url
-        @env['HTTP_REFERER'] || rack_session['user_return_to'] || Rails.application.routes.url_helpers.root_url
+        @env['HTTP_REFERER'] || rack_session['user_return_to'] || Gitlab::Routing.url_helpers.root_url
       end
 
       def route_hash
@@ -74,10 +74,16 @@ module Gitlab
       end
 
       def grack_route
+        # Calling route_hash may be expensive. Only do it if we think there's a possible match
+        return false unless request.path.end_with?('.git/git-upload-pack')
+
         route_hash[:controller] == 'projects/git_http' && route_hash[:action] == 'git_upload_pack'
       end
 
       def lfs_route
+        # Calling route_hash may be expensive. Only do it if we think there's a possible match
+        return false unless request.path.end_with?('/info/lfs/objects/batch')
+
         route_hash[:controller] == 'projects/lfs_api' && route_hash[:action] == 'batch'
       end
     end