Websocket-rails不能在哈希中添加新密钥

Question

我目前正在开发一个应用程序，它使用Rails、Puma和Websocket-rails向客户端推送Twitter流消息。由于某些原因，在导航到索引页(单页应用程序)后，我随机地得到以下错误。我不知道项目代码中的错误发生在哪里，也不知道为什么会发生错误。我非常迷茫，因此任何帮助都是值得感激的。

整个回购可以找到这里。问题肯定出现在lib/twitter_stream.rb中。结果是这样的:在restart_stream的内部是Twitter流连接，每当请求新的搜索词时，我希望它重新启动；但是，每当我连续发出两三次请求时，我就会得到这个错误。

RuntimeError - can't add a new key into hash during iteration:
   () Users/Nasty1/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/bundler/gems/websocket-rails-712fd4e35325/lib/websocket_rails/connection_manager.rb:83:in `open_connection'
   () Users/Nasty1/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/bundler/gems/websocket-rails-712fd4e35325/lib/websocket_rails/connection_manager.rb:55:in `call'
  actionpack (4.2.0) lib/action_dispatch/routing/mapper.rb:51:in `serve'
  actionpack (4.2.0) lib/action_dispatch/journey/router.rb:43:in `block in serve'
  actionpack (4.2.0) lib/action_dispatch/journey/router.rb:30:in `serve'
  actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:802:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/rack/agent_hooks.rb:30:in `traced_call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:55:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/rack/browser_monitoring.rb:23:in `traced_call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:55:in `call'
  rack (1.6.0) lib/rack/etag.rb:24:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/conditionalget.rb:25:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/head.rb:13:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/flash.rb:260:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/session/abstract/id.rb:225:in `context'
  rack (1.6.0) lib/rack/session/abstract/id.rb:220:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/cookies.rb:560:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  activerecord (4.2.0) lib/active_record/query_cache.rb:36:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  activerecord (4.2.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:647:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  activerecord (4.2.0) lib/active_record/migration.rb:378:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:88:in `_run_callbacks'
  activesupport (4.2.0) lib/active_support/callbacks.rb:734:in `_run_call_callbacks'
  activesupport (4.2.0) lib/active_support/callbacks.rb:81:in `run_callbacks'
  actionpack (4.2.0) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/reloader.rb:73:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call'
  better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call'
  better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  web-console (2.0.0) lib/action_dispatch/debug_exceptions.rb:18:in `middleware_call'
  web-console (2.0.0) lib/action_dispatch/debug_exceptions.rb:13:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  railties (4.2.0) lib/rails/rack/logger.rb:38:in `call_app'
  railties (4.2.0) lib/rails/rack/logger.rb:20:in `block in call'
  activesupport (4.2.0) lib/active_support/tagged_logging.rb:68:in `block in tagged'
  activesupport (4.2.0) lib/active_support/tagged_logging.rb:26:in `tagged'
  activesupport (4.2.0) lib/active_support/tagged_logging.rb:68:in `tagged'
  railties (4.2.0) lib/rails/rack/logger.rb:20:in `call'
  quiet_assets (1.1.0) lib/quiet_assets.rb:27:in `call_with_quiet_assets'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/request_id.rb:21:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/methodoverride.rb:22:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/runtime.rb:18:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  activesupport (4.2.0) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  actionpack (4.2.0) lib/action_dispatch/middleware/static.rb:113:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/sendfile.rb:113:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  railties (4.2.0) lib/rails/engine.rb:518:in `call'
  railties (4.2.0) lib/rails/application.rb:164:in `call'
  newrelic_rpm (3.9.9.275) lib/new_relic/agent/instrumentation/middleware_tracing.rb:57:in `call'
  rack (1.6.0) lib/rack/content_length.rb:15:in `call'
  puma (2.11.0) lib/puma/server.rb:507:in `handle_request'
  puma (2.11.0) lib/puma/server.rb:375:in `process_client'
  puma (2.11.0) lib/puma/server.rb:262:in `block in run'
  puma (2.11.0) lib/puma/thread_pool.rb:104:in `block in spawn_thread'

Answer 1

在我的套接字控制器中，我执行了一个单线程阻塞操作，这将最终使所允许的并发连接的数量达到最大值。