Change order of sidekiq LoadBalancing middleware

lib/gitlab/sidekiq_middleware.rb

@@ -26,12 +26,14 @@ module Gitlab
         chain.add ::Gitlab::SidekiqMiddleware::BatchLoader
         chain.add ::Labkit::Middleware::Sidekiq::Server
         chain.add ::Gitlab::SidekiqMiddleware::InstrumentationLogger
-        chain.add ::Gitlab::Database::LoadBalancing::SidekiqServerMiddleware if load_balancing_enabled?
         chain.add ::Gitlab::SidekiqMiddleware::AdminMode::Server
         chain.add ::Gitlab::SidekiqVersioning::Middleware
         chain.add ::Gitlab::SidekiqStatus::ServerMiddleware
         chain.add ::Gitlab::SidekiqMiddleware::WorkerContext::Server
+        # DuplicateJobs::Server should be placed  at the bottom, but before the SidekiqServerMiddleware,
+        # so we can compare the latest WAL location against replica
         chain.add ::Gitlab::SidekiqMiddleware::DuplicateJobs::Server
+        chain.add ::Gitlab::Database::LoadBalancing::SidekiqServerMiddleware if load_balancing_enabled?
       end
     end
 
@@ -42,13 +44,15 @@ module Gitlab
       lambda do |chain|
         chain.add ::Gitlab::SidekiqMiddleware::WorkerContext::Client # needs to be before the Labkit middleware
         chain.add ::Labkit::Middleware::Sidekiq::Client
+        # Sidekiq Client Middleware should be placed before DuplicateJobs::Client middleware,
+        # so we can store WAL location before we deduplicate the job.
+        chain.add ::Gitlab::Database::LoadBalancing::SidekiqClientMiddleware if load_balancing_enabled?
         chain.add ::Gitlab::SidekiqMiddleware::DuplicateJobs::Client
         chain.add ::Gitlab::SidekiqStatus::ClientMiddleware
         chain.add ::Gitlab::SidekiqMiddleware::AdminMode::Client
-        # Size limiter should be placed at the bottom, but before the metrics midleware
+        # Size limiter should be placed at the bottom, but before the metrics middleware
         chain.add ::Gitlab::SidekiqMiddleware::SizeLimiter::Client
         chain.add ::Gitlab::SidekiqMiddleware::ClientMetrics
-        chain.add ::Gitlab::Database::LoadBalancing::SidekiqClientMiddleware if load_balancing_enabled?
       end
     end
 

spec/lib/gitlab/sidekiq_middleware_spec.rb

@@ -66,12 +66,12 @@ RSpec.describe Gitlab::SidekiqMiddleware do
         ::Gitlab::SidekiqMiddleware::BatchLoader,
         ::Labkit::Middleware::Sidekiq::Server,
         ::Gitlab::SidekiqMiddleware::InstrumentationLogger,
-        ::Gitlab::Database::LoadBalancing::SidekiqServerMiddleware,
         ::Gitlab::SidekiqMiddleware::AdminMode::Server,
         ::Gitlab::SidekiqVersioning::Middleware,
         ::Gitlab::SidekiqStatus::ServerMiddleware,
         ::Gitlab::SidekiqMiddleware::WorkerContext::Server,
-        ::Gitlab::SidekiqMiddleware::DuplicateJobs::Server
+        ::Gitlab::SidekiqMiddleware::DuplicateJobs::Server,
+        ::Gitlab::Database::LoadBalancing::SidekiqServerMiddleware
       ]
     end
 
@@ -177,12 +177,12 @@ RSpec.describe Gitlab::SidekiqMiddleware do
       [
         ::Gitlab::SidekiqMiddleware::WorkerContext::Client,
         ::Labkit::Middleware::Sidekiq::Client,
+        ::Gitlab::Database::LoadBalancing::SidekiqClientMiddleware,
         ::Gitlab::SidekiqMiddleware::DuplicateJobs::Client,
         ::Gitlab::SidekiqStatus::ClientMiddleware,
         ::Gitlab::SidekiqMiddleware::AdminMode::Client,
         ::Gitlab::SidekiqMiddleware::SizeLimiter::Client,
-        ::Gitlab::SidekiqMiddleware::ClientMetrics,
-        ::Gitlab::Database::LoadBalancing::SidekiqClientMiddleware
+        ::Gitlab::SidekiqMiddleware::ClientMetrics
       ]
     end