背景：

最近需要做个服务端消息推送的事情，首先就考虑到了Laravel自带的广播功能，它是利用redis的发布订阅功能和前端利用node.js实现的一套集合了Websocket 的功能

前置条件：
后端：

1，安装redis扩展
      composer require predis/predis
2，在config/app.php中打开注释：
      App\Providers\BroadcastServiceProvider::class,
3，在.env中
    APP_URL=http://your_domain.com  #域名
    APP_NAME=YourAppName   #默认laravel即可
    QUEUE_CONNECTION=redis  #redis队列
    BROADCAST_DRIVER=redis  #broadcast的驱动使用redis

前端：

1,npm Install
2,npm install -g laravel-echo-server #https://github.com/tlaverdure/laravel-echo-server
3,npm install --save socket.io-client

公有频道

1,后端代码：

<?php

namespace App\Events;

use Illuminate\Broadcasting\Channel;
use Illuminate\Queue\SerializesModels;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Broadcasting\InteractsWithSockets;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;

class PublicEvent implements ShouldBroadcast
{
    use Dispatchable, InteractsWithSockets, SerializesModels;
    /**
     * Create a new event instance.
     *
     * @return void
     */
    public $msg = '';
    public function __construct($msg)
    {
        $this->msg = $msg;
    }

    /**
     * Get the channels the event should broadcast on.
     *
     * @return \Illuminate\Broadcasting\Channel|array
     */
    public function broadcastOn()
    {
        return new Channel('public');
    }

//    public function broadcastWith()
//    {
//        return [
//            'data' => 'this is public'
//        ];
//    }
}

2,前端代码

<script>
import Echo from 'laravel-echo'

window.io = require('socket.io-client');
window.Echo = new Echo({
    broadcaster: 'socket.io',
    host: window.location.hostname + ':6001',
});

window.Echo.channel('public')
    .listen('PublicEvent', (e) => {
        console.log(e);
    });
</script>

3，打开页面在console,即可以看到我们发送的数据

{msg: "this is public", socket: null}
msg: "this is public"
socket: null
__proto__: Object
}

私有频道

PrivateEvent：

<?php

namespace App\Events;

use App\Models\UserModel;
use Illuminate\Queue\SerializesModels;
use Illuminate\Broadcasting\PrivateChannel;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Broadcasting\InteractsWithSockets;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;

class PrivateEvent implements ShouldBroadcast
{
    use Dispatchable, InteractsWithSockets, SerializesModels;

    public $user;
    public $userId = '';

    /**
     * Create a new event instance.
     *
     * @return void
     */
    public function __construct(UserModel $user)
    {

        $this->user = $user;
        $this->userId = 3590;

        // dd('user.' . $this->user->u_id);
    }

    /**
     * Get the channels the event should broadcast on.
     *
     * @return \Illuminate\Broadcasting\Channel|array
     */
    public function broadcastOn()
    {
        // dd(Auth::user());
        return new PrivateChannel('user.' . $this->userId);
    }

// 精细化返回的数据，如果加了这个函数，公有属性才不会返回而是以这个函数内放回的字段为主
//    public function broadcastWith()
//    {
//        return [
//            'data' => '2424',
//        ];
//    }
}

BroadcastServiceProvider:

<?php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use Illuminate\Support\Facades\Broadcast;

class BroadcastServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        //Broadcast::routes();
        Broadcast::routes(['middleware' => 'api']);
        #routes()参数如果不配置 默认走的是web中间件
        #'middleware' => 'api' 然后广播路由走api中间件，自己也可以定义其他类型的中间件

        require base_path('routes/channels.php'); #加载检查权限的广播路由
    }
}

routes/channels：#广播路由只针对广播的

<?php

/*
|--------------------------------------------------------------------------
| Broadcast Channels
|--------------------------------------------------------------------------
|
| Here you may register all of the event broadcasting channels that your
| application supports. The given channel authorization callbacks are
| used to check if an authenticated user can listen to the channel.
|
*/

//占位符模式
\Illuminate\Support\Facades\Broadcast::channel('user.{userId}', function ($user, $userId) {
    return true;
}, ['guards' => ['api']]);

#{userId}只是占位符
#$user 闭包默认的第一个参数，授权的用户
#$userId 时间模板的公有属性(此时该值为3590即在PrivateEvent构造函数上所赋的值)，也可以是其他的对象
#闭包函数接受多个参数，这个参数由事件里的broadcastOn函数声明的频道决定,如：'user.' . $this->userId . $this->userName 那么就可以接受2个参数userId和userName

//显式的路由模型绑定
\Illuminate\Support\Facades\Broadcast::channel('user.{user2}', function ($user, \App\Models\UserModel $user2) {
    \Illuminate\Support\Facades\Log::info($user);
    return true;
}, ['guards' => ['api']]);
# 注意这里的占位符{user2} 必须 \App\Models\UserModel $user2  这个变量名一样。否则会报错

前端代码

<script>
import Echo from 'laravel-echo'

window.io = require('socket.io-client');
window.Echo = new Echo({
    broadcaster: 'socket.io',
    host: window.location.hostname + ':6001',
    auth: {
         headers: {
             Authorization: 'Bearer ' + 'WVP25lQfJFTpCcuA1rmdadgeXQplMOtobWjL4TvkDD8dMbjOX5pBF4kBwiC9'
         },
     },
});

window.Echo.private('user.3590')
    .listen('PrivateEvent', (e) => { 
            alert(11);
           console.log(1111);
        console.log(e);
    });
</script>

#user.3590 监听的频道
#PrivateEvent 监听的事件
#Authorization 授权，后端会检测如果不对会报错403

页面展示：不出意外会把公有属性全部展示出来，其他的属性不会展示

{
user: {…}, userId: 3590, socket: null}
socket: null
user: {u_id: 3590, u_username: "02125", u_job_number: "", u_warehouse_id: 1, u_department_id: 0, …}
userId: 3590
__proto__: Object
}

参考：
https://xueyuanjun.com/post/19505
http://silverd.cn/2018/06/01/laravel-broadcasting-adv.html