Authorizing Channels

Remember, users must be authorized to listen on private channels. We may define our channel authorization rules in the routes/channels.php file. In this example, we need to verify that any user attempting to listen on the private order.1 channel is actually the creator of the order:

Broadcast::channel('order.{orderId}', function ($user, $orderId) {
    return $user->id === Order::findOrNew($orderId)->user_id;
});

The channel method accepts two arguments: the name of the channel and a callback which returns true or false indicating whether the user is authorized to listen on the channel.

All authorization callbacks receive the currently authenticated user as their first argument and any additional wildcard parameters as their subsequent arguments. In this example, we are using the {orderId} placeholder to indicate that the “ID” portion of the channel name is a wildcard.

Listening For Event Broadcasts
Next, all that remains is to listen for the event in our JavaScript application. We can do this using Laravel Echo. First, we’ll use the private method to subscribe to the private channel. Then, we may use the listen method to listen for the ShippingStatusUpdated event. By default, all of the event’s public properties will be included on the broadcast event:

Echo.private(`order.${orderId}`)
    .listen('ShippingStatusUpdated', (e) => {
        console.log(e.update);
    });

To inform Laravel that a given event should be broadcast, implement the Illuminate\Contracts\Broadcasting\ShouldBroadcast interface on the event class. This interface is already imported into all event classes generated by the framework so you may easily add it to any of your events.

The ShouldBroadcast interface requires you to implement a single method: broadcastOn. The broadcastOn method should return a channel or array of channels that the event should broadcast on. The channels should be instances of Channel, PrivateChannel, or PresenceChannel. Instances of Channel represent public channels that any user may subscribe to, while PrivateChannels and PresenceChannels represent private channels that require channel authorization:

namespace App\Events;

use Illuminate\Broadcasting\Channel;
use Illuminate\Queue\SerializesModels;
use Illuminate\Broadcasting\PrivateChannel;
use Illuminate\Broadcasting\PresenceChannel;
use Illuminate\Broadcasting\InteractsWithSockets;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;

class ServerCreated implements ShouldBroadcast
{
    use SerializesModels;

    public $user;

    /**
     * Create a new event instance.
     *
     * @return void
     */
    public function __construct(User $user)
    {
        $this->user = $user;
    }

    /**
     * Get the channels the event should broadcast on.
     *
     * @return Channel|array
     */
    public function broadcastOn()
    {
        return new PrivateChannel('user.'.$this->user->id);
    }
}

ほんまや、broadcastonって書いてる。
Then, you only need to fire the event as you normally would. Once the event has been fired, a queued job will automatically broadcast the event over your specified broadcast driver.

Broadcast Name
By default, Laravel will broadcast the event using the event’s class name. However, you may customize the broadcast name by defining a broadcastAs method on the event:
なに、次はbroadcastAs

public function broadcastAs()
{
    return 'server.created';
}

When an event is broadcast, all of its public properties are automatically serialized and broadcast as the event’s payload, allowing you to access any of its public data from your JavaScript application. So, for example, if your event has a single public $user property that contains an Eloquent model, the event’s broadcast payload would be:

{
    "user": {
        "id": 1,
        "name": "Patrick Stewart"
        ...
    }
}
public function broadcastWith()
{
    return ['id' => $this->user->id];
}

Broadcast Queue
By default, each broadcast event is placed on the default queue for the default queue connection specified in your queue.php configuration file. You may customize the queue used by the broadcaster by defining a broadcastQueue property on your event class. This property should specify the name of the queue you wish to use when broadcasting:

use Illuminate\Contracts\Broadcasting\ShouldBroadcastNow;

class ShippingStatusUpdated implements ShouldBroadcastNow
{
    //
}
 Broadca
public function broadcastWhen()
{
    return $this->value > 100;
}

Authorizing Channels
Private channels require you to authorize that the currently authenticated user can actually listen on the channel. This is accomplished by making an HTTP request to your Laravel application with the channel name and allowing your application to determine if the user can listen on that channel. When using Laravel Echo, the HTTP request to authorize subscriptions to private channels will be made automatically; however, you do need to define the proper routes to respond to these requests.

Defining Authorization Routes
Thankfully, Laravel makes it easy to define the routes to respond to channel authorization requests. In the BroadcastServiceProvider included with your Laravel application, you will see a call to the Broadcast::routes method. This method will register the /broadcasting/auth route to handle authorization requests:

roadcast::routes();
The Broadcast::routes method will automatically place its routes within the web middleware group; however, you may pass an array of route attributes to the method if you would like to customize the assigned attributes:

Broadcast::routes($attributes);
あれ、broadcastって別にOauthではないよね。

Defining Authorization Callbacks
Next, we need to define the logic that will actually perform the channel authorization. This is done in the routes/channels.php file that is included with your application. In this file, you may use the Broadcast::channel method to register channel authorization callbacks

Broadcast::channel('order.{orderId}', function ($user, $orderId) {
    return $user->id === Order::findOrNew($orderId)->user_id;
});

書き方がむずいな。
The channel method accepts two arguments: the name of the channel and a callback which returns true or false indicating whether the user is authorized to listen on the channel.

All authorization callbacks receive the currently authenticated user as their first argument and any additional wildcard parameters as their subsequent arguments. In this example, we are using the {orderId} placeholder to indicate that the “ID” portion of the channel name is a wildcard.
これjavaもやんのかーーーーーーーー
Authorization Callback Model Binding
Just like HTTP routes, channel routes may also take advantage of implicit and explicit route model binding. For example, instead of receiving the string or numeric order ID, you may request an actual Order model instance:

use App\Order;

Broadcast::channel('order.{order}', function ($user, Order $order) {
    return $user->id === $order->user_id;
});

Defining Channel Classes
If your application is consuming many different channels, your routes/channels.php file could become bulky. So, instead of using Closures to authorize channels, you may use channel classes. To generate a channel class, use the make:channel Artisan command. This command will place a new channel class in the App/Broadcasting directory.

php artisan make:channel OrderChannel
Next, register your channel in your routes/channels.php file:
use App\Broadcasting\OrderChannel;

Broadcast::channel(‘order.{order}’, OrderChannel::class);

Finally, you may place the authorization logic for your channel in the channel class’ join method. This join method will house the same logic you would have typically placed in your channel authorization Closure. Of course, you may also take advantage of channel model binding:

namespace App\Broadcasting;

use App\User;
use App\Order;

class OrderChannel
{
    /**
     * Create a new channel instance.
     *
     * @return void
     */
    public function __construct()
    {
        //
    }

    /**
     * Authenticate the user's access to the channel.
     *
     * @param  \App\User  $user
     * @param  \App\Order  $order
     * @return array|bool
     */
    public function join(User $user, Order $order)
    {
        return $user->id === $order->user_id;
    }
}

Only To Others
When building an application that utilizes event broadcasting, you may substitute the event function with the broadcast function. Like the event function, the broadcast function dispatches the event to your server-side listeners:

broadcast(new ShippingStatusUpdated($update));
However, the broadcast function also exposes the toOthers method which allows you to exclude the current user from the broadcast’s recipients:

broadcast(new ShippingStatusUpdated($update))->toOthers();
To better understand when you may want to use the toOthers method, let’s imagine a task list application where a user may create a new task by entering a task name. To create a task, your application might make a request to a /task end-point which broadcasts the task’s creation and returns a JSON representation of the new task. When your JavaScript application receives the response from the end-point, it might directly insert the new task into its task list like so:

axios.post(‘/task’, task)
.then((response) => {
this.tasks.push(response.data);
});
However, remember that we also broadcast the task’s creation. If your JavaScript application is listening for this event in order to add tasks to the task list, you will have duplicate tasks in your list: one from the end-point and one from the broadcast. You may solve this by using the toOthers method to instruct the broadcaster to not broadcast the event to the current user.

Note: Your event must use the Illuminate\Broadcasting\InteractsWithSockets trait in order to call the toOthers method.

Configuration
When you initialize a Laravel Echo instance, a socket ID is assigned to the connection. If you are using Vue and Axios, the socket ID will automatically be attached to every outgoing request as a X-Socket-ID header. Then, when you call the toOthers method, Laravel will extract the socket ID from the header and instruct the broadcaster to not broadcast to any connections with that socket ID.

If you are not using Vue and Axios, you will need to manually configure your JavaScript application to send the X-Socket-ID header. You may retrieve the socket ID using the Echo.socketId method:

var socketId = Echo.socketId();
そもそもこれって、jsとの通信だけど、どっち側が考えてなかった。laravelのdemo作らんと。

Installing Laravel Echo
Laravel Echo is a JavaScript library that makes it painless to subscribe to channels and listen for events broadcast by Laravel. You may install Echo via the NPM package manager. In this example, we will also install the pusher-js package since we will be using the Pusher broadcaster:

npm install –save laravel-echo pusher-js
Once Echo is installed, you are ready to create a fresh Echo instance in your application’s JavaScript. A great place to do this is at the bottom of the resources/js/bootstrap.js file that is included with the Laravel framework:
pusher.jsってなんか笑えるな。

import Echo from "laravel-echo"

window.Echo = new Echo({
    broadcaster: 'pusher',
    key: 'your-pusher-key'
});
window.Echo = new Echo({
    broadcaster: 'pusher',
    key: 'your-pusher-key',
    cluster: 'eu',
    encrypted: true
});

Using An Existing Client Instance
If you already have a Pusher or Socket.io client instance that you would like Echo to utilize, you may pass it to Echo via the client configuration option:

const client = require(‘pusher-js’);

window.Echo = new Echo({
broadcaster: ‘pusher’,
key: ‘your-pusher-key’,
client: client
});

Notifications
By pairing event broadcasting with notifications, your JavaScript application may receive new notifications as they occur without needing to refresh the page. First, be sure to read over the documentation on using the broadcast notification channel.

Once you have configured a notification to use the broadcast channel, you may listen for the broadcast events using Echo’s notification method. Remember, the channel name should match the class name of the entity receiving the notifications:

Echo.private(`App.User.${userId}`)
.notification((notification) => {
console.log(notification.type);
});
In this example, all notifications sent to App\User instances via the broadcast channel would be received by the callback. A channel authorization callback for the App.User.{id} channel is included in the default BroadcastServiceProvider that ships with the Laravel framework.