Question

David has a great video on how to use Action Cable for Rails 5，对我来说，我在Rails 5上使用的是beta 3版本。

问题是，Action Cable是否只适用于只有一个参数作为data传递的聊天应用？我可以将多个参数传递给speak吗？

RoomChannel（咖啡）：

App.room = App.cable.subscriptions.create "RoomChannel",
  connected: ->
    # Called when the subscription is ready for use on the server

  disconnected: ->
    # Called when the subscription has been terminated by the server

  received: (data) ->
    alert data['message']
    # Called when there's incoming data on the websocket for this channel

  speak: (message) -> # Could I pass in more than one params?
    @perform 'speak', message: message

room_channel.rb：

# Be sure to restart your server when you modify this file. Action Cable runs in a loop that does not support auto reloading.
class RoomChannel < ApplicationCable::Channel
  def subscribed
    stream_from "room_channel"
  end

  def unsubscribed
    # Any cleanup needed when channel is unsubscribed
  end

  def speak(data)
    ActionCable.server.broadcast 'room_channel', message: data['message']
  end
end

如果我可以传递多个参数，那么它适用于哪里：

App.room.speak("foo bar"); # one param so far here.

编辑：

我现在收到两个对象的警报：[object object]

App.room.speak(
    {
      data1: "Data 1 mate",
      data2: "Data 2 mate"
    }
  )

room.coffee：

received: (data1, data2) ->
    alert data1['message']

room_channel.rb：

def speak(data1, data2)
    ActionCable.server.broadcast 'room_channel', message: data1['message'], data2['message']
  end

控制台：

RoomChannel#speak({"message"=>{"data1"=>"Data 1 mate", "data2"=>"Data 2 mate"}})

Answer 1

要将另一个参数传递给actioncable服务器，您可以传递Javascript对象。

然后在服务器端，此Javascript对象表示为哈希。

示例：

客户端

App.room.speak(
    {
      param1: "Data 1 mate",
      param2: "Data 2 mate"
    }
  )

服务器端

def speak(data)
    ActionCable.server.broadcast 'room_channel', param1: data['param1'], param2: data['data2']
  end

并返回客户端

received: (data) ->
    alert data['param1']
    alert data["param2"]

Answer 2

我想我现在可以回答这个问题了。两个参数都被传递但是作为哈希。在控制台中，您将看到两个参数，因此您需要从message中提取值。

保持speak方法正常：

def speak(data)
  ActionCable.server.broadcast 'room_channel', message: data['message']
end

您的receive功能（咖啡）应如下所示：

received: (data) ->
  alert(data.message.data1)
  alert(data.message.data2)

Answer 3

您必须在广播呼叫上传递哈希值，例如：

def broadcast_to_room_channel(title, message)
    data = { title: title, message: message }
    ActionCable.server.broadcast 'room_channel', data
end

Answer 4

我遇到了类似的情况，我需要传递关联的id参数。我使用了form_with辅助函数和数据属性，通过语音传递了参数以创建Post的实例。我发现类似这样的方法有效：

view.html.erb

<%= form_with(model: Post.new) do |f| %>
    <div>
      <%= f.text_area :content, 
          id: 'text', 
          data: { first_id: @first.id, second_id: @second.id } %>
    </div>
<% end %>

chat_room.coffee

speak: (post) ->
firstId = document.getElementById('text').dataset.firstId
secondId = document.getElementById('text').dataset.secondId

@perform 'speak', post: post, first_id: firstId, second_id: secondId

chat_room_channel.rb

def speak(data)
    Post.create! content: data['post'], first_id: data['first_id'], second_id: data['second_id']
end

在引用的同一视频上，我将broadcast逻辑移到了一个工作程序中，在这里您将新创建的Post实例广播到您可以通过{{1}访问的部分内容中}。

使用Rails 5 Action Cable的多个参数

4 个答案: