Add Horizon health check

app/HorizonHealthCheck.php

@@ -0,0 +1,43 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App;
+
+use Laravel\Horizon\Contracts\MasterSupervisorRepository;
+use UKFast\HealthCheck\HealthCheck;
+use UKFast\HealthCheck\Status;
+
+/**
+ * Verify Horizon is running.
+ *
+ * @author https://github.com/dominikager
+ *
+ * @source https://github.com/ans-group/laravel-health-check/issues/78#issue-1847102332
+ */
+class HorizonHealthCheck extends HealthCheck
+{
+    /**
+     * The name for this health check.
+     *
+     * @var string
+     */
+    protected $name = 'horizon';
+
+    public function __construct(private readonly MasterSupervisorRepository $supervisorRepository)
+    {
+    }
+
+    public function status(): Status
+    {
+        $masters = $this->supervisorRepository->all();
+
+        if (count($masters) === 0) {
+            return $this->problem('Horizon is inactive');
+        }
+
+        return collect($masters)->contains(
+            static fn (object $master): bool => $master->status === 'paused'
+        ) ? $this->problem('Horizon is paused') : $this->okay();
+    }
+}

config/healthcheck.php

@@ -20,6 +20,7 @@
         \UKFast\HealthCheck\Checks\RedisHealthCheck::class,
         \UKFast\HealthCheck\Checks\SchedulerHealthCheck::class,
         \UKFast\HealthCheck\Checks\StorageHealthCheck::class,
+        \App\HorizonHealthCheck::class,
     ],
 
     /**