From: Aaron Schulz <aschulz@wikimedia.org>
Date: Wed, 19 Jun 2019 16:05:16 +0000 (+0100)
Subject: rdbms: deprecate unused ILoadBalancer::safeGetLag method
X-Git-Tag: 1.34.0-rc.0~1343
X-Git-Url: http://git.cyclocoop.org/%22.%20generer_url_ecrire%28%22sites_tous%22%2C%22%22%29.%20%22?a=commitdiff_plain;h=b9a67d4710b117504f4c65d2c2071791909d6c5e;p=lhc%2Fweb%2Fwiklou.git

rdbms: deprecate unused ILoadBalancer::safeGetLag method

Change-Id: Ib3bc2862548271613da30ad1be836d28a82e6cc9
---

diff --git a/includes/libs/rdbms/database/Database.php b/includes/libs/rdbms/database/Database.php
index 5451476042..bc8883c3ac 100644
--- a/includes/libs/rdbms/database/Database.php
+++ b/includes/libs/rdbms/database/Database.php
@@ -4245,6 +4245,16 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
 	}
 
 	public function getLag() {
+		if ( $this->getLBInfo( 'master' ) ) {
+			return 0; // this is the master
+		} elseif ( $this->getLBInfo( 'is static' ) ) {
+			return 0; // static dataset
+		}
+
+		return $this->doGetLag();
+	}
+
+	protected function doGetLag() {
 		return 0;
 	}
 
diff --git a/includes/libs/rdbms/database/DatabaseMysqlBase.php b/includes/libs/rdbms/database/DatabaseMysqlBase.php
index b5f83dae0d..ef28f33ac6 100644
--- a/includes/libs/rdbms/database/DatabaseMysqlBase.php
+++ b/includes/libs/rdbms/database/DatabaseMysqlBase.php
@@ -744,7 +744,7 @@ abstract class DatabaseMysqlBase extends Database {
 		return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 	}
 
-	public function getLag() {
+	protected function doGetLag() {
 		if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 			return $this->getLagFromPtHeartbeat();
 		} else {
diff --git a/includes/libs/rdbms/loadbalancer/ILoadBalancer.php b/includes/libs/rdbms/loadbalancer/ILoadBalancer.php
index a2202b6a09..22281c17ed 100644
--- a/includes/libs/rdbms/loadbalancer/ILoadBalancer.php
+++ b/includes/libs/rdbms/loadbalancer/ILoadBalancer.php
@@ -604,22 +604,6 @@ interface ILoadBalancer {
 	 */
 	public function getLagTimes( $domain = false );
 
-	/**
-	 * Get the lag in seconds for a given connection, or zero if this load
-	 * balancer does not have replication enabled.
-	 *
-	 * This should be used in preference to Database::getLag() in cases where
-	 * replication may not be in use, since there is no way to determine if
-	 * replication is in use at the connection level without running
-	 * potentially restricted queries such as SHOW SLAVE STATUS. Using this
-	 * function instead of Database::getLag() avoids a fatal error in this
-	 * case on many installations.
-	 *
-	 * @param IDatabase $conn
-	 * @return int|bool Returns false on error
-	 */
-	public function safeGetLag( IDatabase $conn );
-
 	/**
 	 * Wait for a replica DB to reach a specified master position
 	 *
diff --git a/includes/libs/rdbms/loadbalancer/LoadBalancer.php b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
index 62f45823b7..f0e4b4f47d 100644
--- a/includes/libs/rdbms/loadbalancer/LoadBalancer.php
+++ b/includes/libs/rdbms/loadbalancer/LoadBalancer.php
@@ -1959,6 +1959,21 @@ class LoadBalancer implements ILoadBalancer {
 		return $this->getLoadMonitor()->getLagTimes( $indexesWithLag, $domain ) + $knownLagTimes;
 	}
 
+	/**
+	 * Get the lag in seconds for a given connection, or zero if this load
+	 * balancer does not have replication enabled.
+	 *
+	 * This should be used in preference to Database::getLag() in cases where
+	 * replication may not be in use, since there is no way to determine if
+	 * replication is in use at the connection level without running
+	 * potentially restricted queries such as SHOW SLAVE STATUS. Using this
+	 * function instead of Database::getLag() avoids a fatal error in this
+	 * case on many installations.
+	 *
+	 * @param IDatabase $conn
+	 * @return int|bool Returns false on error
+	 * @deprecated Since 1.34 Use IDatabase::getLag() instead
+	 */
 	public function safeGetLag( IDatabase $conn ) {
 		if ( $this->getServerCount() <= 1 ) {
 			return 0;
@@ -1981,7 +1996,8 @@ class LoadBalancer implements ILoadBalancer {
 			if ( $masterConn ) {
 				$pos = $masterConn->getMasterPos();
 			} else {
-				$masterConn = $this->getConnection( $index, [], self::DOMAIN_ANY, self::CONN_SILENCE_ERRORS );
+				$flags = self::CONN_SILENCE_ERRORS;
+				$masterConn = $this->getConnection( $index, [], self::DOMAIN_ANY, $flags );
 				if ( !$masterConn ) {
 					throw new DBReplicationWaitError(
 						null,
diff --git a/includes/libs/rdbms/loadmonitor/LoadMonitor.php b/includes/libs/rdbms/loadmonitor/LoadMonitor.php
index aa1e9b24b1..1666c275c7 100644
--- a/includes/libs/rdbms/loadmonitor/LoadMonitor.php
+++ b/includes/libs/rdbms/loadmonitor/LoadMonitor.php
@@ -181,25 +181,21 @@ class LoadMonitor implements ILoadMonitor {
 				continue;
 			}
 
-			if ( $conn->getLBInfo( 'is static' ) ) {
-				$lagTimes[$i] = 0;
-			} else {
-				$lagTimes[$i] = $conn->getLag();
-				if ( $lagTimes[$i] === false ) {
-					$this->replLogger->error(
-						__METHOD__ . ": host {db_server} is not replicating?",
-						[ 'db_server' => $host ]
-					);
-				} elseif ( $lagTimes[$i] > $this->lagWarnThreshold ) {
-					$this->replLogger->warning(
-						"Server {host} has {lag} seconds of lag (>= {maxlag})",
-						[
-							'host' => $host,
-							'lag' => $lagTimes[$i],
-							'maxlag' => $this->lagWarnThreshold
-						]
-					);
-				}
+			$lagTimes[$i] = $conn->getLag();
+			if ( $lagTimes[$i] === false ) {
+				$this->replLogger->error(
+					__METHOD__ . ": host {db_server} is not replicating?",
+					[ 'db_server' => $host ]
+				);
+			} elseif ( $lagTimes[$i] > $this->lagWarnThreshold ) {
+				$this->replLogger->warning(
+					"Server {host} has {lag} seconds of lag (>= {maxlag})",
+					[
+						'host' => $host,
+						'lag' => $lagTimes[$i],
+						'maxlag' => $this->lagWarnThreshold
+					]
+				);
 			}
 
 			if ( $close ) {