Use `#use_open_file` for NuGet metadata extraction

instead of `#use_file` which will use an exclusive lock

Changelog: fixed

app/services/packages/nuget/metadata_extraction_service.rb

@@ -28,7 +28,7 @@ module Packages
       def execute
         raise ExtractionError, 'invalid package file' unless valid_package_file?
 
-        extract_metadata(nuspec_file)
+        extract_metadata(nuspec_file_content)
       end
 
       private
@@ -39,6 +39,10 @@ module Packages
         end
       end
 
+      def project
+        package_file.package.project
+      end
+
       def valid_package_file?
         package_file &&
           package_file.package&.nuget? &&
@@ -89,18 +93,39 @@ module Packages
         tags.split(::Packages::Tag::NUGET_TAGS_SEPARATOR)
       end
 
-      def nuspec_file
-        package_file.file.use_file do |file_path|
-          Zip::File.open(file_path) do |zip_file|
-            entry = zip_file.glob('*.nuspec').first
+      def nuspec_file_content
+        with_zip_file do |zip_file|
+          entry = zip_file.glob('*.nuspec').first
 
-            raise ExtractionError, 'nuspec file not found' unless entry
-            raise ExtractionError, 'nuspec file too big' if entry.size > MAX_FILE_SIZE
+          raise ExtractionError, 'nuspec file not found' unless entry
+          raise ExtractionError, 'nuspec file too big' if entry.size > MAX_FILE_SIZE
 
-            entry.get_input_stream.read
+          entry.get_input_stream.read
+        end
+      end
+
+      def with_zip_file(&block)
+        if ::Feature.enabled?(:packages_nuget_archive_new_file_reader, project, default_enabled: :yaml)
+          with_new_file_reader(&block)
+        else
+          with_legacy_file_reader(&block)
+        end
+      end
+
+      def with_legacy_file_reader
+        package_file.file.use_file do |file_path|
+          Zip::File.open(file_path) do |zip_file|
+            yield(zip_file)
           end
         end
       end
+
+      def with_new_file_reader
+        package_file.file.use_open_file do |open_file|
+          zip_file = Zip::File.new(open_file, false, true)
+          yield(zip_file)
+        end
+      end
     end
   end
 end

config/feature_flags/development/packages_nuget_archive_new_file_reader.yml

+---
+name: packages_nuget_archive_new_file_reader
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/62471
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/331799
+milestone: '13.13'
+type: development
+group: group::package
+default_enabled: false

spec/services/packages/nuget/metadata_extraction_service_spec.rb

@@ -3,7 +3,8 @@
 require 'spec_helper'
 
 RSpec.describe Packages::Nuget::MetadataExtractionService do
-  let(:package_file) { create(:nuget_package).package_files.first }
+  let_it_be(:package_file) { create(:nuget_package).package_files.first }
+
   let(:service) { described_class.new(package_file.id) }
 
   describe '#execute' do
@@ -23,12 +24,27 @@ RSpec.describe Packages::Nuget::MetadataExtractionService do
         package_tags: []
       }
 
-      it { is_expected.to eq(expected_metadata) }
+      context 'with packages_nuget_archive_new_file_reader enabled' do
+        before do
+          expect(service).to receive(:with_new_file_reader).and_call_original
+        end
+
+        it { is_expected.to eq(expected_metadata) }
+      end
+
+      context 'with packages_nuget_archive_new_file_reader disabled' do
+        before do
+          stub_feature_flags(packages_nuget_archive_new_file_reader: false)
+          expect(service).to receive(:with_legacy_file_reader).and_call_original
+        end
+
+        it { is_expected.to eq(expected_metadata) }
+      end
     end
 
     context 'with nuspec file' do
       before do
-        allow(service).to receive(:nuspec_file).and_return(fixture_file(nuspec_filepath))
+        allow(service).to receive(:nuspec_file_content).and_return(fixture_file(nuspec_filepath))
       end
 
       context 'with dependencies' do
@@ -57,7 +73,7 @@ RSpec.describe Packages::Nuget::MetadataExtractionService do
       let_it_be(:nuspec_filepath) { 'packages/nuget/with_metadata.nuspec' }
 
       before do
-        allow(service).to receive(:nuspec_file).and_return(fixture_file(nuspec_filepath))
+        allow(service).to receive(:nuspec_file_content).and_return(fixture_file(nuspec_filepath))
       end
 
       it { expect(subject[:license_url]).to eq('https://opensource.org/licenses/MIT') }