Consume daemon

makasim · makasim · commit db0cab16dd35 · 2017-04-14T13:41:47.000+03:00
Allows easily to spawn consume workers. Reload them by USR1 signal and
stop corretnly when the daemon is stopped.
diff --git a/pkg/enqueue/Symfony/ConsumeDaemon.php b/pkg/enqueue/Symfony/ConsumeDaemon.php
@@ -0,0 +1,118 @@
+<?php
+namespace Enqueue\Symfony;
+
+use Symfony\Component\Process\Process;
+use Symfony\Component\Process\ProcessBuilder;
+
+class ConsumeDaemon
+{
+    /**
+     * @var ProcessBuilder
+     */
+    private $workerBuilder;
+
+    /**
+     * @var Process[]
+     */
+    private $workers;
+
+    /**
+     * @param ProcessBuilder $workerBuilder
+     */
+    public function __construct(ProcessBuilder $workerBuilder)
+    {
+        $this->workerBuilder = $workerBuilder;
+        $this->workers = [];
+        $this->interrupt = false;
+    }
+
+    public function start($workersNumber)
+    {
+        /** @var Process[] $workers */
+        $workers = [];
+
+        $handleSignal = function($signal) use (&$workers) {
+            switch ($signal) {
+                case SIGUSR1:
+                    echo 'Daemon is reloading now.'.PHP_EOL;
+
+                    foreach ($workers as $id => $worker) {
+                        $worker->signal(SIGQUIT);
+                    }
+
+                    break;
+                case SIGTERM:  // 15 : supervisor default stop
+                case SIGQUIT:  // 3  : kill -s QUIT
+                case SIGINT:   // 2  : ctrl+c
+                    foreach ($workers as $id => $worker) {
+                        $worker->stop(3, SIGQUIT);
+                    }
+
+                    while ($workers) {
+                        foreach ($workers as $id => $worker) {
+                            if (false == $worker->isRunning()) {
+                                unset($workers[$id]);
+                            }
+                        }
+                    }
+
+                    exit;
+
+                    break;
+                default:
+                    break;
+            }
+        };
+
+        pcntl_signal(SIGTERM, $handleSignal);
+        pcntl_signal(SIGQUIT, $handleSignal);
+        pcntl_signal(SIGINT, $handleSignal);
+        pcntl_signal(SIGUSR1, $handleSignal);
+
+        foreach (range(1, $workersNumber) as $id) {
+            $workers[] = $this->startWorker($id);
+        }
+
+        while (true) {
+            pcntl_signal_dispatch();
+
+            foreach ($workers as $id => $worker) {
+                if (false == $worker->isRunning()) {
+                    echo sprintf('Worker %s exited with status %d', $id, $worker->getExitCode()).PHP_EOL;
+
+                    unset($this->workers[$id]);
+                    $workers[$id] = $this->startWorker($id);
+                }
+            }
+
+            pcntl_signal_dispatch();
+
+            sleep(1);
+        }
+    }
+
+    /**
+     * @param int $workerId
+     *
+     * @return Process
+     */
+    public function startWorker($workerId)
+    {
+        if (array_key_exists($workerId, $this->workers)) {
+            throw new \LogicException(sprintf('Such worker %s is already in pool.', $workerId));
+        }
+
+        echo sprintf('Start worker %s', $workerId).PHP_EOL;
+
+        $process = $this->workerBuilder->getProcess();
+        $process->start(function($type, $buffer) use ($workerId) {
+            echo $workerId.' | '.$buffer;
+        });
+
+        if (false == $process->isStarted()) {
+            throw new \LogicException('Cannot start a worker process.');
+        }
+
+        return $process;
+    }
+}
