Queued notifications in Laravel - Mini Project: Build & Apply

Queued Notifications in Laravel

📖 Scenario: You are building a Laravel application that sends notifications to users. To improve performance, you want to send notifications using Laravel's queue system so that the user does not wait for the notification to be sent.

🎯 Goal: Build a queued notification system in Laravel that sends a notification to a user asynchronously using Laravel's queue feature.

📋 What You'll Learn

Create a notification class that implements the ShouldQueue interface

Set up a queue connection in the configuration

Send the notification to a user using the queue

Ensure the notification is dispatched to the queue properly

💡 Why This Matters

🌍 Real World

Queued notifications improve user experience by sending emails or messages in the background without making users wait during web requests.

💼 Career

Understanding queued notifications is essential for Laravel developers working on scalable applications that handle email, SMS, or other notifications efficiently.

1

Create a Notification Class

Create a notification class called OrderShipped using the artisan command php artisan make:notification OrderShipped. Then, open the OrderShipped.php file and add the ShouldQueue interface to the class declaration and import it with use Illuminate\Contracts\Queue\ShouldQueue;.

Laravel

// Run the artisan command to create the notification class
// Then open OrderShipped.php and add the ShouldQueue interface
// Your code here

Hint

Remember to import the ShouldQueue interface and add it to the notification class declaration.

2

Configure the Queue Connection

Open the config/queue.php file and set the default queue connection by changing the 'default' key to env('QUEUE_CONNECTION', 'database'). Also, ensure you have run php artisan queue:table and php artisan migrate to create the jobs table.

Laravel

 'sync' to 'default' => env('QUEUE_CONNECTION', 'database')

// Your code here

Hint

Set the default queue connection to 'database' in the config/queue.php file.

3

Send Notification Using Queue

In a controller or route closure, send the OrderShipped notification to a user instance using the notify() method. Use the syntax $user->notify(new OrderShipped()); to dispatch the notification to the queue.

Laravel

<?php

// Assume $user is an instance of App\Models\User
// Send the OrderShipped notification to $user using notify()

// Your code here

Hint

Use the notify() method on the user object to send the notification.

4

Run the Queue Worker

Start the Laravel queue worker by running the command php artisan queue:work in your terminal. This will process the queued notifications and send them asynchronously.

Laravel

// Run the queue worker in the terminal
// Your code here

Hint

Open your terminal and run php artisan queue:work to start processing queued jobs.

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