Migrate correlation and tracing code to LabKit

This change is a fairly straightforward refactor to extract the tracing
and correlation-id code from the gitlab rails codebase into the new
LabKit-Ruby project.

The corresponding import into LabKit-Ruby was in
https://gitlab.com/gitlab-org/labkit-ruby/merge_requests/1

The code itself remains very similar for now.

Extracting it allows us to reuse it in other projects, such as
Gitaly-Ruby. This will give us the advantages of correlation-ids and
distributed tracing in that project too.

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/gitlab/gitaly_client.rb b/lib/gitlab/gitaly_client.rb
index 726c4d95da9..c432317eb24 100644
--- a/lib/gitlab/gitaly_client.rb
+++ b/lib/gitlab/gitaly_client.rb
@@ -52,9 +52,9 @@ module Gitlab
     end
 
     def self.interceptors
-      return [] unless Gitlab::Tracing.enabled?
+      return [] unless Labkit::Tracing.enabled?
 
-      [Gitlab::Tracing::GRPCInterceptor.instance]
+      [Labkit::Tracing::GRPCInterceptor.instance]
     end
     private_class_method :interceptors
 
@@ -218,7 +218,7 @@ module Gitlab
       feature = feature_stack && feature_stack[0]
       metadata['call_site'] = feature.to_s if feature
       metadata['gitaly-servers'] = address_metadata(remote_storage) if remote_storage
-      metadata['x-gitlab-correlation-id'] = Gitlab::CorrelationId.current_id if Gitlab::CorrelationId.current_id
+      metadata['x-gitlab-correlation-id'] = Labkit::Correlation::CorrelationId.current_id if Labkit::Correlation::CorrelationId.current_id
 
       metadata.merge!(server_feature_flags)