From c58afe45b06ce1e380f55e40c0becb3ef930f709 Mon Sep 17 00:00:00 2001
From: Timo Tijhof <krinklemail@gmail.com>
Date: Sat, 15 Sep 2018 00:02:12 +0100
Subject: [PATCH] debug: Allow the DBQuery channel to be used

Follows-up 81e8d7af4129eb56 and e861191b2cdceeeecee.

When using $wgShowDebug, $wgDebugComments, or $wgDebugLogFile
locally, or when using the 'log' attribute with X-Wikimedia-Debug,
all channels should be enabled and logged. But, the DBQuery logs
are currently going nowhere.

The code for MWDebug::query() is intercepting it, even if
$wgDebugToolbar is not enabled.

And after that, the code for wfLogDBError was intercepting it,
again, even if $wgDBerrorLog is not enabled.

Bug: T202764
Change-Id: I710c26a9e9c30fea20975d1bc24e1f0af077c2ad
---
 includes/debug/MWDebug.php             |  7 +++----
 includes/debug/logger/LegacyLogger.php | 28 ++++++++++++++++++++++----
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/includes/debug/MWDebug.php b/includes/debug/MWDebug.php
index 2189498687..ae7f948f29 100644
--- a/includes/debug/MWDebug.php
+++ b/includes/debug/MWDebug.php
@@ -349,12 +349,11 @@ class MWDebug {
 	 * @param string $function
 	 * @param bool $isMaster
 	 * @param float $runTime Query run time
-	 * @return int ID number of the query to pass to queryTime or -1 if the
-	 *  debugger is disabled
+	 * @return bool True if debugger is enabled, false otherwise
 	 */
 	public static function query( $sql, $function, $isMaster, $runTime ) {
 		if ( !self::$enabled ) {
-			return -1;
+			return false;
 		}
 
 		// Replace invalid UTF-8 chars with a square UTF-8 character
@@ -389,7 +388,7 @@ class MWDebug {
 			'time' => $runTime,
 		];
 
-		return count( self::$query ) - 1;
+		return true;
 	}
 
 	/**
diff --git a/includes/debug/logger/LegacyLogger.php b/includes/debug/logger/LegacyLogger.php
index d4a79d931f..d566a47a30 100644
--- a/includes/debug/logger/LegacyLogger.php
+++ b/includes/debug/logger/LegacyLogger.php
@@ -93,18 +93,38 @@ class LegacyLogger extends AbstractLogger {
 	 * @return null
 	 */
 	public function log( $level, $message, array $context = [] ) {
+		global $wgDBerrorLog;
+
 		if ( is_string( $level ) ) {
 			$level = self::$levelMapping[$level];
 		}
-		if ( $this->channel === 'DBQuery' && isset( $context['method'] )
-			&& isset( $context['master'] ) && isset( $context['runtime'] )
+		if ( $this->channel === 'DBQuery'
+			&& isset( $context['method'] )
+			&& isset( $context['master'] )
+			&& isset( $context['runtime'] )
 		) {
-			MWDebug::query( $message, $context['method'], $context['master'], $context['runtime'] );
-			return; // only send profiling data to MWDebug profiling
+			// Also give the query information to the MWDebug tools
+			$enabled = MWDebug::query(
+				$message,
+				$context['method'],
+				$context['master'],
+				$context['runtime']
+			);
+			if ( $enabled ) {
+				// If we the toolbar was enabled, return early so that we don't
+				// also log the query to the main debug output.
+				return;
+			}
 		}
 
+		// If this is a DB-related error, and the site has $wgDBerrorLog
+		// configured, rewrite the channel as wfLogDBError instead.
+		// Likewise, if the site does not use  $wgDBerrorLog, it should
+		// configurable like any other channel via $wgDebugLogGroups
+		// or $wgMWLoggerDefaultSpi.
 		if ( isset( self::$dbChannels[$this->channel] )
 			&& $level >= self::$levelMapping[LogLevel::ERROR]
+			&& $wgDBerrorLog
 		) {
 			// Format and write DB errors to the legacy locations
 			$effectiveChannel = 'wfLogDBError';
-- 
2.20.1