From 47de1649462818ee0a038aea9ed2233eb5e1cda4 Mon Sep 17 00:00:00 2001
From: Benjamin Gaussorgues <benjamin.gaussorgues@nextcloud.com>
Date: Thu, 21 Aug 2025 10:52:03 +0200
Subject: [PATCH] feat(comments): add basic OpenMetrics exporter

Signed-off-by: Benjamin Gaussorgues <benjamin.gaussorgues@nextcloud.com>
---
 apps/comments/appinfo/info.xml                |  4 ++
 .../composer/composer/autoload_classmap.php   |  1 +
 .../composer/composer/autoload_static.php     |  1 +
 .../lib/OpenMetrics/CommentsCountMetric.php   | 52 +++++++++++++++++++
 4 files changed, 58 insertions(+)
 create mode 100644 apps/comments/lib/OpenMetrics/CommentsCountMetric.php

diff --git a/apps/comments/appinfo/info.xml b/apps/comments/appinfo/info.xml
index 956a8fe3914..efab11b68d8 100644
--- a/apps/comments/appinfo/info.xml
+++ b/apps/comments/appinfo/info.xml
@@ -38,6 +38,10 @@
 		</providers>
 	</activity>
 
+	<openmetrics>
+		<exporter>OCA\Comments\OpenMetrics\CommentsCountMetric</exporter>
+	</openmetrics>
+
 	<collaboration>
 		<plugins>
 			<plugin type="autocomplete-sort">OCA\Comments\Collaboration\CommentersSorter</plugin>
diff --git a/apps/comments/composer/composer/autoload_classmap.php b/apps/comments/composer/composer/autoload_classmap.php
index 6db5c6a232b..a6cd74eeaaa 100644
--- a/apps/comments/composer/composer/autoload_classmap.php
+++ b/apps/comments/composer/composer/autoload_classmap.php
@@ -22,5 +22,6 @@ return array(
     'OCA\\Comments\\MaxAutoCompleteResultsInitialState' => $baseDir . '/../lib/MaxAutoCompleteResultsInitialState.php',
     'OCA\\Comments\\Notification\\Listener' => $baseDir . '/../lib/Notification/Listener.php',
     'OCA\\Comments\\Notification\\Notifier' => $baseDir . '/../lib/Notification/Notifier.php',
+    'OCA\\Comments\\OpenMetrics\\CommentsCountMetric' => $baseDir . '/../lib/OpenMetrics/CommentsCountMetric.php',
     'OCA\\Comments\\Search\\CommentsSearchProvider' => $baseDir . '/../lib/Search/CommentsSearchProvider.php',
 );
diff --git a/apps/comments/composer/composer/autoload_static.php b/apps/comments/composer/composer/autoload_static.php
index 60359abb6d0..6dee6b1fc96 100644
--- a/apps/comments/composer/composer/autoload_static.php
+++ b/apps/comments/composer/composer/autoload_static.php
@@ -37,6 +37,7 @@ class ComposerStaticInitComments
         'OCA\\Comments\\MaxAutoCompleteResultsInitialState' => __DIR__ . '/..' . '/../lib/MaxAutoCompleteResultsInitialState.php',
         'OCA\\Comments\\Notification\\Listener' => __DIR__ . '/..' . '/../lib/Notification/Listener.php',
         'OCA\\Comments\\Notification\\Notifier' => __DIR__ . '/..' . '/../lib/Notification/Notifier.php',
+        'OCA\\Comments\\OpenMetrics\\CommentsCountMetric' => __DIR__ . '/..' . '/../lib/OpenMetrics/CommentsCountMetric.php',
         'OCA\\Comments\\Search\\CommentsSearchProvider' => __DIR__ . '/..' . '/../lib/Search/CommentsSearchProvider.php',
     );
 
diff --git a/apps/comments/lib/OpenMetrics/CommentsCountMetric.php b/apps/comments/lib/OpenMetrics/CommentsCountMetric.php
new file mode 100644
index 00000000000..d0c9233b7c3
--- /dev/null
+++ b/apps/comments/lib/OpenMetrics/CommentsCountMetric.php
@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\Comments\OpenMetrics;
+
+use Generator;
+use OC\DB\Connection;
+use OCP\OpenMetrics\IMetricFamily;
+use OCP\OpenMetrics\Metric;
+use OCP\OpenMetrics\MetricType;
+use Override;
+
+class CommentsCountMetric implements IMetricFamily {
+	public function __construct(
+		private Connection $connection,
+	) {
+	}
+
+	#[Override]
+	public function name(): string {
+		return 'comments';
+	}
+
+	#[Override]
+	public function type(): MetricType {
+		return MetricType::gauge;
+	}
+
+	#[Override]
+	public function unit(): string {
+		return 'comments';
+	}
+
+	#[Override]
+	public function help(): string {
+		return 'Number of comments';
+	}
+
+	#[Override]
+	public function metrics(): Generator {
+		$qb = $this->connection->getQueryBuilder();
+		$result = $qb->select($qb->func()->count())
+			->from('comments')
+			->where($qb->expr()->eq('verb', $qb->expr()->literal('comment')))
+			->executeQuery();
+
+		yield new Metric($result->fetchOne(), [], time());
+	}
+}