Debug Redis calls

ruby/lib/ci/queue.rb

@@ -24,6 +24,13 @@ module Warnings
       RESERVED_LOST_TEST = :RESERVED_LOST_TEST
     end
 
+    def logger
+      @logger ||= begin
+        FileUtils.mkdir_p("log")
+        Logger.new('log/ci-queue.log')
+      end
+    end
+
     def requeueable?(test_result)
       requeueable.nil? || requeueable.call(test_result)
     end

ruby/lib/ci/queue/redis/base.rb

@@ -11,6 +11,20 @@ class Base
           ::SocketError, # https://github.com/redis/redis-rb/pull/631
         ].freeze
 
+        module RedisInstrumentation
+          def call(command, redis_config)
+            result = super
+            CI::Queue.logger.info("#{command}: #{result}") if ENV['CI_QUEUE_DEBUG']
+            result
+          end
+
+          def call_pipelined(commands, redis_config)
+            result = super
+            CI::Queue.logger.info("#{command}: #{result}") if ENV['CI_QUEUE_DEBUG']
+            result
+          end
+        end
+
         def initialize(redis_url, config)
           @redis_url = redis_url
           if ::Redis::VERSION > "5.0.0"
@@ -19,6 +33,7 @@ def initialize(redis_url, config)
               # Booting a CI worker is costly, so in case of a Redis blip,
               # it makes sense to retry for a while before giving up.
               reconnect_attempts: [0, 0, 0.1, 0.5, 1, 3, 5],
+              middlewares: [RedisInstrumentation]
             )
           else
             @redis = ::Redis.new(url: redis_url)