WIP: put info into redis that server is restarting

Author: Flink

lib/docker_manager/upgrader.rb

@@ -53,6 +53,7 @@ def upgrade
     percent(5)
 
     log("Cycling #{@web_server.server_name}, to free up memory")
+    Discourse.redis.setex("docker_manager:upgrade:server_restarting", 2.minutes.to_i, 1)
     @web_server.reload(launcher_pid, method(:log))
 
     percent(10)
@@ -167,6 +168,7 @@ def upgrade
     raise ex
   ensure
     @repos.each(&:stop_upgrading)
+    Discourse.redis.del("docker_manager:upgrade:server_restarting")
   end
 
   def publish(type, value)