面向nil：NilClass的Rails ActionCable未定义方法`debug'

Question

我正在尝试将ActionCable实现到Rails 5.2.1应用程序。我添加了congif / cable.yml文件，因为它丢失了，并且生成了频道，但是我尝试使用commant从Rails控制台广播消息

ActionCable.server.broadcast 'comments:1', { asd: true }

它返回我错误消息：

undefined method `debug' for nil:NilClass

channels / comments_channel.rb

class CommentsChannel < ApplicationCable::Channel
  def subscribed
    stream_from "comments:1"
  end

  def unsubscribed
    stop_all_streams
  end
end

assets / javascripts / channels / comments.js

App.comments = App.cable.subscriptions.create("CommentsChannel", {
  connected: function() {
    // Called when the subscription is ready for use on the server
  },

  disconnected: function() {
    // Called when the subscription has been terminated by the server
  },

  received: function(data) {
    console.log(data)
  }
});

config / cable.yml

development:
 adapter: redis
 url: redis://localhost:6379/1

test:
  adapter: async

production:
  adapter: redis
  url: redis://localhost:6379/1