Laravel Horizon

Introduction
Horizon provides a beautiful dashboard and code-driven configuration for your Laravel powered Redis queues. Horizon allows you to easily monitor key metrics of your queue system such as job throughput, runtime, and job failures.

All of your worker configuration is stored in a single, simple configuration file, allowing your configuration to stay in source control where your entire team can collaborate.

Installation
Note: Due to its usage of async process signals, Horizon requires PHP 7.1+. Secondly, you should ensure that your queue driver is set to redis in your queue configuration file.

You may use Composer to install Horizon into your Laravel project:
composer require laravel/horizon

After installing Horizon, publish its assets using the vendor:publish Artisan command:
php artisan vendor:publish –provider=”Laravel\Horizon\HorizonServiceProvider”

Configuration
After publishing Horizon’s assets, its primary configuration file will be located at config/horizon.php. This configuration file allows you to configure your worker options and each configuration option includes a description of its purpose, so be sure to thoroughly explore this file.

Balance Options
Horizon allows you to choose from three balancing strategies: simple, auto, and false. The simple strategy, which is the default, splits incoming jobs evenly between processes:

‘balance’ => ‘simple’,

The auto strategy adjusts the number of worker processes per queue based on the current workload of the queue. For example, if your notifications queue has 1,000 waiting jobs while your render queue is empty, Horizon will allocate more workers to your notifications queue until it is empty. When the balance option is set to false, the default Laravel behavior will be used, which processes queues in the order they are listed in your configuration.

Job Trimming
The horizon configuration file allows you to configure how long recent and failed jobs should be persisted (in minutes). By default, recent jobs are kept for one hour while failed jobs are kept for a week:

‘trim’ => [
‘recent’ => 60,
‘failed’ => 10080,
],

Dashboard Authentication
Horizon exposes a dashboard at /horizon. By default, you will only be able to access this dashboard in the local environment. To define a more specific access policy for the dashboard, you should use the Horizon::auth method. The auth method accepts a callback which should return true or false, indicating whether the user should have access to the Horizon dashboard. Typically, you should call Horizon::auth in the boot method of your AppServiceProvider:

Horizon::auth(function ($request) {
    // return true / false;
});

Running Horizon
Once you have configured your workers in the config/horizon.php configuration file, you may start Horizon using the horizon Artisan command. This single command will start all of your configured workers:

php artisan horizon

You may pause the Horizon process and instruct it to continue processing jobs using the horizon:pause and horizon:continue Artisan commands:

php artisan horizon:pause

php artisan horizon:continue
You may gracefully terminate the master Horizon process on your machine using the horizon:terminate Artisan command. Any jobs that Horizon is currently processing will be completed and then Horizon will exit:

php artisan horizon:terminate

Tags
Horizon allows you to assign “tags” to jobs, including mailables, event broadcasts, notifications, and queued event listeners. In fact, Horizon will intelligently and automatically tag most jobs depending on the Eloquent models that are attached to the job. For example, take a look at the following job:

video = $video;
}

/**
* Execute the job.
*
* @return void
*/
public function handle()
{
//
}
}
If this job is queued with an App\Video instance that has an id of 1, it will automatically receive the tag App\Video:1. This is because Horizon will examine the job’s properties for any Eloquent models. If Eloquent models are found, Horizon will intelligently tag the job using the model’s class name and primary key:

$video = App\Video::find(1);

App\Jobs\RenderVideo::dispatch($video);
Manually Tagging
If you would like to manually define the tags for one of your queueable objects, you may define a tags method on the class:

class RenderVideo implements ShouldQueue
{
/**
* Get the tags that should be assigned to the job.
*
* @return array
*/
public function tags()
{
return [‘render’, ‘video:’.$this->video->id];
}
}
Notifications
Note: Before using notifications, you should add the guzzlehttp/guzzle Composer package to your project. When configuring Horizon to send SMS notifications, you should also review the prerequisites for the Nexmo notification driver.

If you would like to be notified when one of your queues has a long wait time, you may use the Horizon::routeMailNotificationsTo, Horizon::routeSlackNotificationsTo, and Horizon::routeSmsNotificationsTo methods. You may call these methods from your application’s AppServiceProvider:

Horizon::routeMailNotificationsTo(‘example@example.com’);
Horizon::routeSlackNotificationsTo(‘slack-webhook-url’, ‘#channel’);
Horizon::routeSmsNotificationsTo(‘15556667777’);
Configuring Notification Wait Time Thresholds
You may configure how many seconds are considered a “long wait” within your config/horizon.php configuration file. The waits configuration option within this file allows you to control the long wait threshold for each connection / queue combination:

‘waits’ => [
‘redis:default’ => 60,
],
Metrics
Horizon includes a metrics dashboard which provides information on your job and queue wait times and throughput. In order to populate this dashboard, you should configure Horizon’s snapshot Artisan command to run every five minutes via your application’s scheduler:

/**
* Define the application’s command schedule.
*
* @param \Illuminate\Console\Scheduling\Schedule $schedule
* @return void
*/
protected function schedule(Schedule $schedule)
{
$schedule->command(‘horizon:snapshot’)->everyFiveMinutes();
}