From 54a1b20aea8464709794e693a5eebdd33f60366c Mon Sep 17 00:00:00 2001
From: Johannes Meyer <johannes.meyer@icinga.com>
Date: Tue, 20 Apr 2021 14:58:25 +0200
Subject: [PATCH] Introduce hook `RedisHealth`

---
 library/Icingadb/ProvidedHook/RedisHealth.php | 51 +++++++++++++++++++
 run.php                                       |  1 +
 2 files changed, 52 insertions(+)
 create mode 100644 library/Icingadb/ProvidedHook/RedisHealth.php

diff --git a/library/Icingadb/ProvidedHook/RedisHealth.php b/library/Icingadb/ProvidedHook/RedisHealth.php
new file mode 100644
index 00000000..6e2dc1c1
--- /dev/null
+++ b/library/Icingadb/ProvidedHook/RedisHealth.php
@@ -0,0 +1,51 @@
+<?php
+
+// Icinga DB Web | (c) 2021 Icinga GmbH | GPLv2
+
+namespace Icinga\Module\Icingadb\ProvidedHook;
+
+use Exception;
+use Icinga\Application\Hook\HealthHook;
+use Icinga\Module\Icingadb\Common\Database;
+use Icinga\Module\Icingadb\Common\IcingaRedis;
+use Icinga\Module\Icingadb\Model\Instance;
+
+class RedisHealth extends HealthHook
+{
+    use Database;
+    use IcingaRedis;
+
+    public function getName()
+    {
+        return 'Icinga Redis';
+    }
+
+    public function checkHealth()
+    {
+        try {
+            $redis = $this->getIcingaRedis();
+
+            $lastIcingaHeartbeat = $this->getLastIcingaHeartbeat($redis);
+            if ($lastIcingaHeartbeat === false) {
+                $this->setState(self::STATE_UNKNOWN);
+                $this->setMessage(t("Can't connect to Icinga Redis: phpredis>=4.3.0 required"));
+                return;
+            } elseif ($lastIcingaHeartbeat === null) {
+                $lastIcingaHeartbeat = time();
+            }
+
+            $instance = Instance::on($this->getDb())->columns('heartbeat')->first();
+            $outdatedDbHeartbeat = $instance->heartbeat < time() - 60;
+            if (! $outdatedDbHeartbeat || $instance->heartbeat <= $lastIcingaHeartbeat) {
+                $this->setState(self::STATE_OK);
+                $this->setMessage(t('Icinga Redis available and up to date.'));
+            } elseif ($instance->heartbeat > $lastIcingaHeartbeat) {
+                $this->setState(self::STATE_CRITICAL);
+                $this->setMessage(t('Icinga Redis outdated. Make sure Icinga 2 is running and connected to Redis.'));
+            }
+        } catch (Exception $e) {
+            $this->setState(self::STATE_UNKNOWN);
+            $this->setMessage(sprintf(t("Can't connect to Icinga Redis: %s"), $e->getMessage()));
+        }
+    }
+}
diff --git a/run.php b/run.php
index 79dc5c11..d5af9d46 100644
--- a/run.php
+++ b/run.php
@@ -7,3 +7,4 @@
 $this->provideHook('ApplicationState');
 $this->provideHook('X509/Sni');
 $this->provideHook('health', 'IcingaHealth');
+$this->provideHook('health', 'RedisHealth');