Add BuildQueueWorker for injecting redis-keys

app/models/ci/build.rb

@@ -81,6 +81,12 @@ module Ci
     end
 
     state_machine :status do
+      after_transition any => [:pending] do |build|
+        build.run_after_commit do
+            BuildQueueWorker.perform_async(id)
+        end
+      end
+
       after_transition pending: :running do |build|
         build.run_after_commit do
           BuildHooksWorker.perform_async(id)

app/workers/build_queue_worker.rb

@@ -0,0 +1,18 @@
+class BuildQueueWorker
+  include Sidekiq::Worker
+  include BuildQueue
+
+  def perform(build_id)
+    Ci::Build.find_by(id: build_id).try do |build|
+      project.runners.select do |runner|
+        if runner.can_pick?(build)
+          # Inject last_update into Redis
+          Gitlab::Redis.with do |redis]
+            new_update = Time.new.inspect
+            redis.set(current_runner_redis_key, new_update, ex: 60.minutes)
+          end
+        end
+      end
+    end
+  end
+end

lib/ci/api/helpers.rb

@@ -62,6 +62,7 @@ module Ci
 
       def current_runner_redis_key
         @runner_redis_key ||= "#{current_runner.token}_#{current_runner.tag_list}"
+      end
 
       def get_runner_version_from_params
         return unless params["info"].present?