Memoize GitLab logger to reduce open file descriptors

We see that in gitlab-org/gitlab-ee#3664 that if we log a lot of
data in Sidekiq workers, the number of open file descriptors
reaches over 1000. To avoid this, we can memoize the logger per
thread via RequestStore.

Closes gitlab-org/gitlab-ee#3664

1 files changed, 12 insertions, 0 deletions

diff --git a/spec/lib/gitlab/app_logger_spec.rb b/spec/lib/gitlab/app_logger_spec.rb
new file mode 100644
index 00000000000..c86d30ce6df
--- /dev/null
+++ b/spec/lib/gitlab/app_logger_spec.rb
@@ -0,0 +1,12 @@
+require 'spec_helper'
+
+describe Gitlab::AppLogger, :request_store do
+  subject { described_class }
+
+  it 'builds a logger once' do
+    expect(::Logger).to receive(:new).and_call_original
+
+    subject.info('hello world')
+    subject.error('hello again')
+  end
+end