Queued notifications in Laravel

Introduction

Queued notifications let your app send messages in the background. This keeps your app fast and smooth for users.

When sending emails or SMS that might take time to deliver

When you want to avoid slowing down user actions by waiting for notifications

When sending many notifications at once to avoid server overload

When you want to retry sending notifications if they fail

When you want to schedule notifications to be sent later

Syntax

Laravel

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

class InvoicePaid extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable)
    {
        return ['mail'];
    }

    public function toMail($notifiable)
    {
        return (new MailMessage)
                    ->line('Your invoice has been paid!')
                    ->action('View Invoice', url('/invoices'))
                    ->line('Thank you for using our app!');
    }
}

Implementing ShouldQueue tells Laravel to queue the notification.

Use the Queueable trait to get helpful queue features like delay and retry.

Examples

A simple queued notification that sends a welcome email.

Laravel

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

class WelcomeUser extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable)
    {
        return ['mail'];
    }

    public function toMail($notifiable)
    {
        return (new MailMessage)
                    ->line('Welcome to our app!')
                    ->line('We are happy to have you.');
    }
}

Edge case: Notification with no delivery channels. It will not send anything but still queues.

Laravel

use Illuminate\Notifications\Notification;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Bus\Queueable;

class EmptyNotification extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable)
    {
        return [];
    }
}

Queued notification sending SMS via Nexmo channel.

Laravel

use Illuminate\Notifications\Notification;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Bus\Queueable;
use Illuminate\Notifications\Messages\NexmoMessage;

class SmsNotification extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable)
    {
        return ['nexmo'];
    }

    public function toNexmo($notifiable)
    {
        return (new NexmoMessage)
                    ->content('Your SMS notification.');
    }
}

Sample Program

This example shows a complete queued notification class OrderShipped. It sends an email with order details. The notification is queued because it implements ShouldQueue.

In the usage example, a user is found and notified. The notification is added to the queue, so the app does not wait for the email to send.

Laravel

<?php

namespace App\Notifications;

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

class OrderShipped extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable)
    {
        return ['mail'];
    }

    public function toMail($notifiable)
    {
        return (new MailMessage)
                    ->subject('Your Order Has Shipped')
                    ->line('Good news! Your order has been shipped.')
                    ->action('Track Order', url('/orders/track'))
                    ->line('Thank you for shopping with us!');
    }
}

// Usage example in a controller or command:

use App\Notifications\OrderShipped;
use App\Models\User;

$user = User::find(1); // Find user to notify

// Before sending notification
echo "Sending notification to user: {$user->email}\n";

$user->notify(new OrderShipped());

// The notification is queued and sent in background

echo "Notification queued successfully.\n";

Important Notes

Queued notifications run in the background, so your app stays fast.

Make sure to run a queue worker (like php artisan queue:work) to process queued notifications.

Time complexity depends on queue system but sending notifications asynchronously is faster for user requests.

Summary

Queued notifications send messages without slowing down your app.

Implement ShouldQueue and use Queueable trait to queue notifications.

Run a queue worker to process and send queued notifications.

Practice

1. What is the main benefit of using queued notifications in Laravel?

easy

A. They automatically retry failed notifications indefinitely.

B. They allow notifications to be sent only during business hours.

C. They send messages without slowing down your app.

D. They encrypt notification content for security.

Solution

1. Step 1: Understand queued notifications purpose

   Queued notifications delay sending to avoid blocking app processes.

2. Step 2: Identify the main benefit

   This means the app stays fast because sending happens in the background.

3. Final Answer:

   They send messages without slowing down your app. -> Option C

4. Quick Check:

   Queued notifications improve app speed = B [OK]

Hint: Queued notifications run in background to keep app fast [OK]

Common Mistakes:

• Thinking queued notifications encrypt messages
• Assuming they only send during specific hours
• Believing they retry indefinitely without limits

2. Which interface must a Laravel notification implement to be queued?

easy

A. QueueInterface

B. Queueable

C. ShouldNotify

D. ShouldQueue

Solution

1. Step 1: Recall Laravel notification queue setup

   Notifications must implement the ShouldQueue interface to be queued.

2. Step 2: Differentiate interface and trait

   Queueable is a trait to help with queue features, not an interface.

3. Final Answer:

   ShouldQueue -> Option D

4. Quick Check:

   Implement ShouldQueue to queue notifications = A [OK]

Hint: Implement ShouldQueue interface to queue notifications [OK]

Common Mistakes:

• Confusing Queueable trait with interface
• Using non-existent interfaces like ShouldNotify
• Assuming QueueInterface is required

3. Given this notification class snippet, what will happen when notify() is called?

use Illuminate\Notifications\Notification;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;

class InvoicePaid extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable)
    {
        return ['mail'];
    }

    public function toMail($notifiable)
    {
        return (new MailMessage)->line('Invoice paid.');
    }
}

medium

A. The notification will be sent immediately without queuing.

B. The notification will be queued and sent asynchronously.

C. The notification will fail because Queueable trait is missing.

D. The notification will send via SMS instead of mail.

Solution

1. Step 1: Check if notification implements ShouldQueue

   The class implements ShouldQueue, so it will be queued.

2. Step 2: Confirm use of Queueable trait and mail channel

   Queueable trait is used, and via() returns 'mail', so mail will be sent asynchronously.

3. Final Answer:

   The notification will be queued and sent asynchronously. -> Option B

4. Quick Check:

   ShouldQueue + Queueable = queued notification = D [OK]

Hint: Implement ShouldQueue and use Queueable to queue notifications [OK]

Common Mistakes:

• Assuming Queueable trait is optional
• Thinking notification sends immediately despite ShouldQueue
• Confusing mail channel with SMS

4. What is wrong with this notification class if it does not queue as expected?

use Illuminate\Notifications\Notification;
use Illuminate\Bus\Queueable;

class OrderShipped extends Notification
{
    use Queueable;

    public function via($notifiable)
    {
        return ['mail'];
    }

    public function toMail($notifiable)
    {
        return (new MailMessage)->line('Order shipped.');
    }
}

medium

A. It is missing the ShouldQueue interface implementation.

B. The Queueable trait should not be used here.

C. The via() method must return 'database' to queue notifications.

D. The toMail() method must be named toQueuedMail() to queue.

Solution

1. Step 1: Check interface implementation for queuing

   The class uses Queueable trait but does not implement ShouldQueue interface.

2. Step 2: Understand queuing requirements

   Without ShouldQueue, Laravel sends notification immediately, ignoring queue.

3. Final Answer:

   It is missing the ShouldQueue interface implementation. -> Option A

4. Quick Check:

   Must implement ShouldQueue to queue notifications = A [OK]

Hint: Implement ShouldQueue interface to enable queuing [OK]

Common Mistakes:

• Thinking Queueable trait alone queues notifications
• Believing via() channel affects queuing
• Renaming toMail() method incorrectly

5. You want to send a notification that queues and retries up to 3 times if it fails. Which code snippet correctly sets this up? A)

class PaymentFailed extends Notification implements ShouldQueue
{
    use Queueable;

    public $tries = 3;

    public function via($notifiable) { return ['mail']; }
}

B)

class PaymentFailed extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable) { return ['mail']; }

    public function retryTimes() { return 3; }
}

C)

class PaymentFailed extends Notification
{
    use Queueable;

    public $tries = 3;

    public function via($notifiable) { return ['mail']; }
}

D)

class PaymentFailed extends Notification implements ShouldQueue
{
    use Queueable;

    public function via($notifiable) { return ['mail']; }

    public $maxRetries = 3;
}

hard

A. Correctly sets retry attempts with public $tries property.

B. Uses retryTimes() method which Laravel does not recognize.

C. Missing ShouldQueue interface, so notification won't queue.

D. Uses $maxRetries property which is not used by Laravel.

Solution

1. Step 1: Identify queuing and retry setup

   Laravel uses public $tries property to set retry attempts on queued jobs/notifications.

2. Step 2: Check interface and property correctness

   Correctly sets retry attempts with public $tries property. implements ShouldQueue and sets public $tries = 3 correctly.

3. Final Answer:

   Correctly sets retry attempts with public $tries property. -> Option A

4. Quick Check:

   Use public $tries for retries in queued notifications = A [OK]

Hint: Set public $tries = 3 and implement ShouldQueue to retry [OK]

Common Mistakes:

• Using non-existent retryTimes() method
• Forgetting to implement ShouldQueue interface
• Using wrong property name like $maxRetries