Redis 未连接到 channel.js

Question

我还没有在网上的任何地方看到这个问题的解决方案，所以这里是。我正在使用 ActionCable 设置简单的通知。当我通过控制台或我的应用程序发送广播时，ActionCable 成功并且没有错误。

    ActionCable.server.broadcast("notifications_channel_1", { notification: "Testing" })

[ActionCable] Broadcasting to notifications_channel_1: {:notification=>"Testing"} => 0

我也可以在我的 redis 服务器上看到它

1605237545.900905 [1 127.0.0.1:52106] "publish" "notifications_channel_1" "{"notification":"Testing"}"

问题是我的 channel.js 中没有收到任何数据，它目前只是写入控制台以进行故障排除。

通知_channel.js

    import consumer from "./consumer"
    
    
    consumer.subscriptions.create("NotificationsChannel", {
    
      connected() {
        console.log("connected to the server!")
      },
    
      disconnected() {
        console.log("disconnected from the server")
      },
    
      received(data) {
          console.log("Receiving:");
          console.log(data.content);
      }
      }

);

在浏览器中，我可以看到我的“已连接到服务器！”显示，所以我知道我已连接，但按下我设置的测试按钮不会产生“接收：[数据]”。以下是我的应用程序中所有相关代码部分：

config/initializers/redis.rb

    redis_host = Rails.application.secrets.redis && Rails.application.secrets.redis['host'] || 'localhost'
    redis_port = Rails.application.secrets.redis && Rails.application.secrets.redis['port'] || 6379
    
    # The constant below will represent ONE connection, present globally in models, controllers, views etc for the instance. No need to do Redis.new everytime
    REDIS = Redis.new(host: redis_host, port: redis_port.to_i)

environments/development.rb

      Rails.root.join('config/cable.yml')
      config.action_cable.url = "ws://localhost:3000/cable"

cable.yml

    development:
      adapter: redis
      url: redis://127.0.0.1:6379/1

index.html.erb

    <%= link_to "Test Notifications", test_path, method: :post %>

notification_test 控制器动作

      def notification_test
        @project = Project.first
        create_notification(current_user, @project, "teammate",
                            "#{@project.name}: Added to the team! Check out your new dashboard by visiting the project!")
      end

create_notification application_controller.rb

中的函数

      def create_notification(user, project, link, body)
        notification = Notification.new(user_id: user.id, project_id: project.id, 
                                        link: link, body: body)
        notification.save
      end

notification.rb

  after_create_commit { NotificationBroadcastJob.perform_later self }

notification_broadcast_job.rb

    class NotificationBroadcastJob < ApplicationJob
      queue_as :default
    
      def perform(notification)
        ActionCable.server.broadcast("notifications_channel_#{notification.user_id}", { 
        notification: render_notification(notification) })
      end
    
      private
    
      def render_notification(notification)
        ApplicationController.renderer.render(partial: 'notifications/alerts', locals: { notification: notification })
      end
    end

notifications_channel.rb

    class NotificationsChannel < ApplicationCable::Channel
      def subscribed
        stream_from "notifications_#{current_user.id}"
    
      end
    
      def unsubscribed
        stop_all_streams
      end
    end

notifications/_alerts.html.erb

    <% if defined?(notification) %>>
      <div class="uk-container">
        <div uk-alert="animation">
          <a class="uk-alert-close" uk-close></a>
          <%= notification.body %>
        </div>
      </div>
    <% end %>

申请.html.erb

    <%= render 'notifications/alerts' %>

我看到有人说这是一个 rails 5 的问题，用 rails 6 解决了，但我是运行 rails 6 并且仍然有这个问题问题。

    rails --version

Rails 6.0.3.4

有解决办法吗？如何让漂亮的“接收：[数据]”显示在我的控制台中？

Answer 1

问题源于您订阅的方式 NotificationsChannel 您没有传递用户 ID，所以您只是订阅了“NotificationsChannel”

如果您将广播替换为

ActionCable.server.broadcast("notifications_channel", { notification: "Testing" })

你的流

class NotificationsChannel < ApplicationCable::Channel
  def subscribed
    stream_from "notifications_channel"
  end
end

然后客户端订阅中的接收回调将起作用，但由于您想要的是向特定用户发送通知，因此有多种方法可以完成此操作

使用 stream_for 并直接流式传输到模型，这对您来说超级简单
订阅您正在创建的确切频道。

如果您选择加入选项一，那么您只需将 stream_from 替换为 stream_for

class NotificationsChannel < ApplicationCable::Channel
  def subscribed
    stream_for current_user
  end
end

此处无需更改，保持客户端代码不变。

如果您选择加入选项二，则使用

进行流式传输

class NotificationsChannel < ApplicationCable::Channel
  def subscribed
    stream_from "notifications_#{params[:user_id]}"
  end
end

你的客户应该像这样创建一个订阅

consumer.subscriptions.create({channel: "NotificationsChannel", user_id: 1}), {
  connected() {
    console.log("connected to the server!");
  },

  disconnected() {
    console.log("disconnected from the server");
  },

  received(data) {
    console.log("Receiving:");
    console.log(data.content);
  },
});

Redis 未连接到 channel.js

Redis not connecting to channel.js

ruby

ruby-on-rails

redis

actioncable