Laravel 5.3 - Single Notification for User Collection (followers)

Question

When I have a single notifiable user, a single entry in the notifications table is inserted, along with a mail/sms sent which is perfectly working via channels.

The issue is when I have a user collection, a list of 1k users following me, and I post an update. Here is what happens when using the Notifiable trait as suggested for multi-user case:

1. 1k mails/sms sent (issue is not here)
2. 1k notification entries added to the DB's notifications table

It seems that adding 1k notifications to the DB's notifications table is not an optimal solution. Since the toArray data is the same, and everything else in the DB's notifications table is the same for 1k rows, with the only difference being the notifiable_id of the user notifiable_type.

An optimal solution out of the box would be:

1. Laravel would pick up the fact that it's an array notifiable_type
2. Save a single notification as notifiable_type user_array or user with notifiable_id 0 (zero would only be used to signify it's a multi notifiable user)

3. Create/Use another table notifications_read using the notification_id it just created as the foreign_key and insert 1k rows, of just these fields:

   notification_id notifiable_id notifiable_type read_at

I am hoping there is already a way to do this as I am at this point in my application and would love to use the built in Notifications and channels for this situation, as I am firing off emails/sms notifications, which is fine to repeat 1k times I think, but it's the entry of the same data into the database that is the problem that needs to be optimized.

Any thoughts/ideas how to proceed in this situation?

Answer 1

Updated 2017-01-14: implemented more correct approach

Quick example:

use Illuminate\Support\Facades\Notification;
use App\Notifications\SomethingCoolHappen;

Route::get('/step1', function () {
    // example - my followers
    $followers = App\User::all();

    // notify them
    Notification::send($followers, new SomethingCoolHappen(['arg1' => 1, 'arg2' => 2]));
});

Route::get('/step2', function () {
    // my follower
    $user = App\User::find(10);

    // check unread subnotifications
    foreach ($user->unreadSubnotifications as $subnotification) {
        var_dump($subnotification->notification->data);
        $subnotification->markAsRead();
    }
});

How to make it work?

Step 1 - migration - create table (subnotifications)

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateSubnotificationsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('subnotifications', function (Blueprint $table) {
            // primary key
            $table->increments('id')->primary();

            // notifications.id
            $table->uuid('notification_id');

            // notifiable_id and notifiable_type
            $table->morphs('notifiable');

            // follower - read_at
            $table->timestamp('read_at')->nullable();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('subnotifications');
    }
}

Step 2 - let's create a model for new subnotifications table

<?php
// App\Notifications\Subnotification.php
namespace App\Notifications;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Notifications\DatabaseNotification;
use Illuminate\Notifications\DatabaseNotificationCollection;

class Subnotification extends Model
{
    // we don't use created_at/updated_at
    public $timestamps = false;

    // nothing guarded - mass assigment allowed
    protected $guarded = [];

    // cast read_at as datetime
    protected $casts = [
        'read_at' => 'datetime',
    ];

    // set up relation to the parent notification
    public function notification()
    {
        return $this->belongsTo(DatabaseNotification::class);
    }

    /**
     * Get the notifiable entity that the notification belongs to.
     */
    public function notifiable()
    {
        return $this->morphTo();
    }

    /**
     * Mark the subnotification as read.
     *
     * @return void
     */
    public function markAsRead()
    {
        if (is_null($this->read_at)) {
            $this->forceFill(['read_at' => $this->freshTimestamp()])->save();
        }
    }
}

Step 3 - create a custom database notification channel
Updated: using static variable $map to keep first notification id and insert next notifications (with the same data) without creating a record in notifications table

<?php
// App\Channels\SubnotificationsChannel.php
namespace App\Channels;

use Illuminate\Notifications\DatabaseNotification;
use Illuminate\Notifications\Notification;

class SubnotificationsChannel
{
    /**
     * Send the given notification.
     *
     * @param  mixed                                  $notifiable
     * @param  \Illuminate\Notifications\Notification $notification
     *
     * @return void
     */
    public function send($notifiable, Notification $notification)
    {
        static $map = [];

        $notificationId = $notification->id;

        // get notification data
        $data = $this->getData($notifiable, $notification);

        // calculate hash
        $hash = md5(json_encode($data));

        // if hash is not in map - create parent notification record
        if (!isset($map[$hash])) {
            // create original notification record with empty notifiable_id
            DatabaseNotification::create([
                'id'              => $notificationId,
                'type'            => get_class($notification),
                'notifiable_id'   => 0,
                'notifiable_type' => get_class($notifiable),
                'data'            => $data,
                'read_at'         => null,
            ]);

            $map[$hash] = $notificationId;
        } else {
            // otherwise use another/first notification id
            $notificationId = $map[$hash];
        }

        // create subnotification
        $notifiable->subnotifications()->create([
            'notification_id' => $notificationId,
            'read_at'         => null
        ]);
    }

    /**
     * Prepares data
     *
     * @param mixed                                  $notifiable
     * @param \Illuminate\Notifications\Notification $notification
     *
     * @return mixed
     */
    public function getData($notifiable, Notification $notification)
    {
        return $notification->toArray($notifiable);
    }
}

Step 4 - create a notification
Updated: now notification supports all channels, not only subnotifications

<?php
// App\Notifications\SomethingCoolHappen.php
namespace App\Notifications;

use App\Channels\SubnotificationsChannel;
use Illuminate\Bus\Queueable;
use Illuminate\Notifications\Notification;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Notifications\Messages\MailMessage;

class SomethingCoolHappen extends Notification
{
    use Queueable;

    protected $data;

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

    /**
     * Get the notification's delivery channels.
     *
     * @param  mixed  $notifiable
     * @return array
     */
    public function via($notifiable)
    {
        /**
         * THIS IS A GOOD PLACE FOR DETERMINING NECESSARY CHANNELS
         */
        $via = [];
        $via[] = SubnotificationsChannel::class;
        //$via[] = 'mail';
        return $via;
    }

    /**
     * Get the mail representation of the notification.
     *
     * @param  mixed  $notifiable
     * @return \Illuminate\Notifications\Messages\MailMessage
     */
    public function toMail($notifiable)
    {
        return (new MailMessage)
                    ->line('The introduction to the notification.')
                    ->action('Notification Action', 'https://laravel.com')
                    ->line('Thank you for using our application!');
    }

    /**
     * Get the array representation of the notification.
     *
     * @param  mixed  $notifiable
     * @return array
     */
    public function toArray($notifiable)
    {
        return $this->data;
    }
}

Step 5 - helper trait for "followers"

<?php
// App\Notifications\HasSubnotifications.php
namespace App\Notifications;

trait HasSubnotifications
{
    /**
     * Get the entity's notifications.
     */
    public function Subnotifications()
    {
        return $this->morphMany(Subnotification::class, 'notifiable')
            ->orderBy('id', 'desc');
    }

    /**
     * Get the entity's read notifications.
     */
    public function readSubnotifications()
    {
        return $this->Subnotifications()
            ->whereNotNull('read_at');
    }

    /**
     * Get the entity's unread notifications.
     */
    public function unreadSubnotifications()
    {
        return $this->Subnotifications()
            ->whereNull('read_at');
    }
}

Step 6 - update your Users model
Updated: no required followers method

namespace App;

use App\Notifications\HasSubnotifications;
use Illuminate\Notifications\Notifiable;
use Illuminate\Foundation\Auth\User as Authenticatable;

class User extends Authenticatable
{
    use Notifiable;

    /**
     * Adding helpers to followers:
     *
     * $user->subnotifications - all subnotifications
     * $user->unreadSubnotifications - all unread subnotifications
     * $user->readSubnotifications - all read subnotifications
     */
    use HasSubnotifications;

    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    protected $fillable = [
        'name', 'email', 'password',
    ];

    /**
     * The attributes that should be hidden for arrays.
     *
     * @var array
     */
    protected $hidden = [
        'password', 'remember_token',
    ];
}

Answer 2

Yes you are right i guess with the default Notifiable trait, you could create a custom channel.

You can check the Illuminate\Notifications\Channels\DatabaseChannel class for default creation and adopt it to a pivot-table one.

Hope this helps to create a new channel with a pivot table. Also, implement a HasDatabasePivotNotifications trait (or similar name) to your own Notifiable trait.