Remove feature flag for GPG cleanup

This will make sure that when cleanup fails, an exception will be
raised.

This also increases the time we'll try to cleanup in Sidekiq, as it
appeared we still had some failures there.

changelogs/unreleased/bvl-remove-cleanup-feature-flag.yml

+---
+title: Try longer to clean up after using a gpg-keychain and raise exption if the
+  cleanup fails
+merge_request: 20718
+author:
+type: fixed

lib/gitlab/gpg.rb

@@ -5,7 +5,7 @@ module Gitlab
     extend self
 
     CleanupError = Class.new(StandardError)
-    BG_CLEANUP_RUNTIME_S = 2
+    BG_CLEANUP_RUNTIME_S = 10
     FG_CLEANUP_RUNTIME_S = 0.5
 
     MUTEX = Mutex.new
@@ -107,19 +107,18 @@ module Gitlab
       begin
         cleanup_tmp_dir(tmp_dir)
       rescue CleanupError => e
+        folder_contents = Dir.children(tmp_dir)
         # This means we left a GPG-agent process hanging. Logging the problem in
         # sentry will make this more visible.
         Gitlab::Sentry.track_exception(e,
                                        issue_url: 'https://gitlab.com/gitlab-org/gitlab/issues/20918',
-                                       extra: { tmp_dir: tmp_dir })
+                                       extra: { tmp_dir: tmp_dir, contents: folder_contents })
       end
 
       tmp_keychains_removed.increment unless File.exist?(tmp_dir)
     end
 
     def cleanup_tmp_dir(tmp_dir)
-      return FileUtils.remove_entry(tmp_dir, true) if Feature.disabled?(:gpg_cleanup_retries)
-
       # Retry when removing the tmp directory failed, as we may run into a
       # race condition:
       # The `gpg-agent` agent process may clean up some files as well while

spec/lib/gitlab/gpg_spec.rb

@@ -177,6 +177,25 @@ describe Gitlab::Gpg do
       end.not_to raise_error
     end
 
+    it 'tracks an exception when cleaning up the tmp dir fails' do
+      expected_exception = described_class::CleanupError.new('cleanup failed')
+      expected_tmp_dir = nil
+
+      expect(described_class).to receive(:cleanup_tmp_dir).and_raise(expected_exception)
+      allow(Gitlab::Sentry).to receive(:track_exception)
+
+      described_class.using_tmp_keychain do
+        expected_tmp_dir = described_class.current_home_dir
+        FileUtils.touch(File.join(expected_tmp_dir, 'dummy.file'))
+      end
+
+      expect(Gitlab::Sentry).to have_received(:track_exception).with(
+        expected_exception,
+        issue_url: 'https://gitlab.com/gitlab-org/gitlab/issues/20918',
+        extra: { tmp_dir: expected_tmp_dir, contents: ['dummy.file'] }
+      )
+    end
+
     shared_examples 'multiple deletion attempts of the tmp-dir' do |seconds|
       let(:tmp_dir) do
         tmp_dir = Dir.mktmpdir
@@ -211,15 +230,6 @@ describe Gitlab::Gpg do
 
         expect(File.exist?(tmp_dir)).to be false
       end
-
-      it 'does not retry when the feature flag is disabled' do
-        stub_feature_flags(gpg_cleanup_retries: false)
-
-        expect(FileUtils).to receive(:remove_entry).with(tmp_dir, true).and_call_original
-        expect(Retriable).not_to receive(:retriable)
-
-        described_class.using_tmp_keychain {}
-      end
     end
 
     it_behaves_like 'multiple deletion attempts of the tmp-dir', described_class::FG_CLEANUP_RUNTIME_S