控制台中的ActionCable.server.broadcast始终返回0

Question

我正在尝试使actioncable正常工作，但是当我在Rails控制台中发出ActionCable.server.broadcast“ discussion”，{asdf：true}时，它总是返回0。

我在cable.yml中运行并配置了Redis服务器。

任何有关我在做错事情的建议都会得到赞赏。

铁路

DiscussionChannel is transmitting the subscription confirmation
DiscussionChannel is streaming from discussion_channel

Rails控制台

Running via Spring preloader in process 17262
Loading development environment (Rails 5.2.2)
2.6.0 :001 > ActionCable.server.broadcast "discussion", {asdf: true}
[ActionCable] Broadcasting to discussion: {:asdf=>true}
 => 0 

discussion_channel.rb

class DiscussionChannel < ApplicationCable::Channel
  def subscribed
     stream_from "discussion_channel"
  end

  def unsubscribed
  end

end

discussion.coffee

App.discussion = App.cable.subscriptions.create "DiscussionChannel",
  connected: ->

  disconnected: ->

  received: (data) ->
     console.log(data)