From 9a9b43756272b5153a639d94758ec30e06b3c2d5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Julius=20H=C3=A4rtl?= <jus@bitgrid.net>
Date: Sat, 16 Dec 2023 13:08:33 +0100
Subject: [PATCH] feat: Add logging for transaction time
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Julius Härtl <jus@bitgrid.net>
---
 lib/private/DB/Connection.php | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/lib/private/DB/Connection.php b/lib/private/DB/Connection.php
index e3fda3e464fdb..d3cc93cdbe009 100644
--- a/lib/private/DB/Connection.php
+++ b/lib/private/DB/Connection.php
@@ -79,6 +79,8 @@ class Connection extends PrimaryReadReplicaConnection {
 	/** @var DbDataCollector|null */
 	protected $dbDataCollector = null;
 
+	protected ?float $transactionActiveSince = null;
+
 	/**
 	 * Initializes a new instance of the Connection class.
 	 *
@@ -306,6 +308,7 @@ protected function logQueryToFile(string $sql): void {
 			// FIXME:  Improve to log the actual target db host
 			$isPrimary = $this->connections['primary'] === $this->_conn;
 			$prefix .= ' ' . ($isPrimary === true ? 'primary' : 'replica') . ' ';
+			$prefix .= ' ' . $this->getTransactionNestingLevel() . ' ';
 
 			file_put_contents(
 				$this->systemConfig->getValue('query_log_file', ''),
@@ -618,4 +621,31 @@ protected function performConnect(?string $connectionName = null): bool {
 		}
 		return $result;
 	}
+
+	public function beginTransaction() {
+		if (!$this->inTransaction()) {
+			$this->transactionActiveSince = microtime(true);
+		}
+		return parent::beginTransaction();
+	}
+
+	public function commit() {
+		$result = parent::commit();
+		if ($this->getTransactionNestingLevel() === 0) {
+			$timeTook = microtime(true) - $this->transactionActiveSince;
+			$this->transactionActiveSince = null;
+			if ($timeTook > 1) {
+				$this->logger->warning('Transaction took longer then 1s: ' . $timeTook, ['exception' => new \Exception('Long running transaction')]);
+			}
+		}
+		return $result;
+	}
+
+	public function rollBack() {
+		$result = parent::rollBack();
+		if ($this->getTransactionNestingLevel() === 0) {
+			$this->transactionActiveSince = null;
+		}
+		return $result;
+	}
 }