Batch load only data from same repository when lazy object is accessed

By specifying `key`, we get a different lazy batch loader for each
repository, which means that accessing a lazy object from one repository
will only result in that repository's objects being fetched, not those
of other repositories, saving us some unnecessary Gitaly lookups.

1 files changed, 4 insertions, 3 deletions

diff --git a/app/graphql/resolvers/full_path_resolver.rb b/app/graphql/resolvers/full_path_resolver.rb
index 8d3da33e8d2..0f1a64b6c58 100644
--- a/app/graphql/resolvers/full_path_resolver.rb
+++ b/app/graphql/resolvers/full_path_resolver.rb
@@ -11,10 +11,11 @@ module Resolvers
     end
 
     def model_by_full_path(model, full_path)
-      BatchLoader.for(full_path).batch(key: "#{model.model_name.param_key}:full_path") do |full_paths, loader|
+      BatchLoader.for(full_path).batch(key: model) do |full_paths, loader, args|
         # `with_route` avoids an N+1 calculating full_path
-        results = model.where_full_path_in(full_paths).with_route
-        results.each { |project| loader.call(project.full_path, project) }
+        args[:key].where_full_path_in(full_paths).with_route.each do |project|
+          loader.call(project.full_path, project)
+        end
       end
     end
   end