Fixed redis reconnect handling when passwords are used in luaEval()

Change-Id: Ifc974e6787d180f9b14624481ffe7c456f689254

diff --git a/includes/clientpool/RedisConnectionPool.php b/includes/clientpool/RedisConnectionPool.php
index f7653eb..c8e98a7 100644 (file)
--- a/includes/clientpool/RedisConnectionPool.php
+++ b/includes/clientpool/RedisConnectionPool.php
@@ -283,6 +283,25 @@ class RedisConnectionPool {
                        }
                }
        }
+
+       /**
+        * Resend an AUTH request to the redis server (useful after disconnects)
+        *
+        * This method is for internal use only
+        *
+        * @param string $server
+        * @param Redis $conn
+        * @return bool Success
+        */
+       public function reauthenticateConnection( $server, Redis $conn ) {
+               if ( $this->password !== null ) {
+                       if ( !$conn->auth( $this->password ) ) {
+                               wfDebugLog( 'redis', "Authentication error connecting to $server" );
+                               return false;
+                       }
+               }
+               return true;
+       }
 }
 
 /**
@@ -324,10 +343,21 @@ class RedisConnRef {
        public function luaEval( $script, array $params, $numKeys ) {
                $sha1 = sha1( $script ); // 40 char hex
                $conn = $this->conn; // convenience
+               $server = $this->server; // convenience
 
                // Try to run the server-side cached copy of the script
                $conn->clearLastError();
                $res = $conn->evalSha( $sha1, $params, $numKeys );
+               // If we got a permission error reply that means that (a) we are not in
+               // multi()/pipeline() and (b) some connection problem likely occured. If
+               // the password the client gave was just wrong, an exception should have
+               // been thrown back in getConnection() previously.
+               if ( preg_match( '/^ERR operation not permitted\b/', $conn->getLastError() ) ) {
+                       $this->pool->reauthenticateConnection( $server, $conn );
+                       $conn->clearLastError();
+                       $res = $conn->eval( $script, $params, $numKeys );
+                       wfDebugLog( 'redis', "Used automatic re-authentication for Lua script $sha1." );
+               }
                // If the script is not in cache, use eval() to retry and cache it
                if ( preg_match( '/^NOSCRIPT/', $conn->getLastError() ) ) {
                        $conn->clearLastError();
@@ -336,7 +366,6 @@ class RedisConnRef {
                }
 
                if ( $conn->getLastError() ) { // script bug?
-                       $server = $this->server;
                        wfDebugLog( 'redis', "Lua script error on server $server: " . $conn->getLastError() );
                }