1 files changed, 59 insertions, 0 deletions
diff --git a/library/X509/Scheduler.php b/library/X509/Scheduler.php
new file mode 100644
index 0000000..0963016
--- /dev/null
+++ b/library/X509/Scheduler.php
@@ -0,0 +1,59 @@
+<?php
+// Icinga Web 2 X.509 Module | (c) 2018 Icinga GmbH | GPLv2
+
+namespace Icinga\Module\X509;
+
+use Cron\CronExpression;
+use Icinga\Application\Logger;
+use React\EventLoop\Factory as Loop;
+
+class Scheduler
+{
+    protected $loop;
+
+    public function __construct()
+    {
+        $this->loop = Loop::create();
+    }
+
+    public function add($name, $cronSchedule, callable $callback)
+    {
+        if (! CronExpression::isValidExpression($cronSchedule)) {
+            throw new \RuntimeException('Invalid cron expression');
+        }
+
+        $now = new \DateTime();
+
+        $expression = new CronExpression($cronSchedule);
+
+        if ($expression->isDue($now)) {
+            $this->loop->futureTick($callback);
+        }
+
+        $nextRuns = $expression->getMultipleRunDates(2, $now);
+
+        $interval = $nextRuns[0]->getTimestamp() - $now->getTimestamp();
+
+        $period = $nextRuns[1]->getTimestamp() - $nextRuns[0]->getTimestamp();
+
+        Logger::info('Scheduling job %s to run at %s.', $name, $nextRuns[0]->format('Y-m-d H:i:s'));
+
+        $loop = function () use (&$loop, $name, $callback, $period) {
+            $callback();
+
+            $nextRun = (new \DateTime())
+                ->add(new \DateInterval("PT{$period}S"));
+
+            Logger::info('Scheduling job %s to run at %s.', $name, $nextRun->format('Y-m-d H:i:s'));
+
+            $this->loop->addTimer($period, $loop);
+        };
+
+        $this->loop->addTimer($interval, $loop);
+    }
+
+    public function run()
+    {
+        $this->loop->run();
+    }
+}