This setup includes:
1️⃣ On-Demand Worker → Starts only when needed & exits after job completion.
2️⃣ Continuous Worker → Runs 24/7, processing jobs continuously.
3️⃣ Queue File (queue.php) → Adds jobs to Beanstalkd.
4️⃣ Supervisor Configuration → Manages continuous workers.

---

✅ Step 1: Install Required Packages

If not installed, install Beanstalkd and Composer dependencies:

sudo apt install beanstalkd -y
composer require pda/pheanstalk

Start Beanstalkd:

sudo systemctl enable --now beanstalkd

---

✅ Step 2: Queue File (queue.php)

This file adds jobs to Beanstalkd.

📄 queue.php

<?php
require 'vendor/autoload.php';
use Pheanstalk\Pheanstalk;

$pheanstalk = Pheanstalk::create('127.0.0.1');
$tube = 'testtube';

// Example job data
$data = [
    'task' => 'send_email',
    'email' => '[email protected]',
    'message' => 'Hello, your order is confirmed!',
    'timestamp' => time(),
];

// Add job to queue
$pheanstalk->useTube($tube)->put(json_encode($data));

echo "Job added to queue.\n";

🔹 Run this file every time you need to add a job:

php queue.php

---

✅ Step 3: On-Demand Worker (worker-once.php)

This worker runs only when needed and exits after finishing the job.

📄 worker-once.php

<?php
require 'vendor/autoload.php';
use Pheanstalk\Pheanstalk;

$pheanstalk = Pheanstalk::create('127.0.0.1');
$tube = 'testtube';

// Try to reserve a job (wait up to 5 seconds)
$job = $pheanstalk->watch($tube)->reserve(5);

if ($job) {
    $data = json_decode($job->getData(), true);
    echo "Processing job: " . print_r($data, true) . "\n";

    // Simulate job execution
    sleep(2);

    // Remove job from queue
    $pheanstalk->delete($job);

    echo "Job completed.\n";
} else {
    echo "No job found. Exiting.\n";
    exit;
}

🔹 Run this manually or with exec() when needed:

php worker-once.php

🔹 Or trigger it via PHP when a job is added:

exec("php worker-once.php > /dev/null 2>&1 &");

---

✅ Step 4: Continuous Worker (worker.php)

This worker runs indefinitely and processes jobs as they arrive.

📄 worker.php

<?php
require 'vendor/autoload.php';
use Pheanstalk\Pheanstalk;

$pheanstalk = Pheanstalk::create('127.0.0.1');
$tube = 'testtube';

echo "Continuous worker started...\n";

while (true) {
    $job = $pheanstalk->watch($tube)->reserve();
    
    if ($job) {
        $data = json_decode($job->getData(), true);
        echo "Processing job: " . print_r($data, true) . "\n";

        // Simulate job execution
        sleep(2);

        // Remove job from queue
        $pheanstalk->delete($job);

        echo "Job completed.\n";
    }
}

🔹 This will keep running & never exit unless stopped manually.

---

✅ Step 5: Supervisor Configuration

Now, let's configure Supervisor to manage the continuous worker.

1️⃣ Open Supervisor config file

sudo nano /etc/supervisor/conf.d/worker.conf

2️⃣ Add this configuration:

[program:worker]
command=php /path/to/worker.php
autostart=true
autorestart=true
numprocs=5
redirect_stderr=true
stdout_logfile=/var/log/worker.log

3️⃣ Apply changes:

sudo supervisorctl reread
sudo supervisorctl update
sudo supervisorctl start worker

🔹 This will run 5 continuous worker instances and restart them if they crash.

---

✅ Final Workflow

1. Add jobs using php queue.php

2. On-demand worker (worker-once.php) runs when needed & exits after completing a job.
3. Continuous worker (worker.php) keeps running to process jobs in real-time.
4. Supervisor ensures continuous workers stay running.

---

🎯 Bonus: Automate On-Demand Workers

If you want to start on-demand workers dynamically based on job count, use this PHP script:

📄 start-workers.php

<?php
exec("php worker-once.php > /dev/null 2>&1 &");
exec("php worker-once.php > /dev/null 2>&1 &");
exec("php worker-once.php > /dev/null 2>&1 &");
exec("php worker-once.php > /dev/null 2>&1 &");
exec("php worker-once.php > /dev/null 2>&1 &");
echo "Started 5 on-demand workers.\n";

🔹 Run this to start 5 workers only when needed:

php start-workers.php

---

🚀 Final Takeaways

✅ On-demand worker (worker-once.php) → Runs & exits after finishing one job.
✅ Continuous worker (worker.php) → Runs indefinitely for real-time job processing.
✅ Queue file (queue.php) → Adds jobs to Beanstalkd.
✅ Supervisor manages continuous workers → Ensures worker.php always runs.
✅ On-demand workers can be triggered dynamically when jobs are added.

💡 This is a scalable, efficient PHP job queue system! 🚀