Merge "rdbms: add setTempTablesOnlyMode() to suppress CONN_TRX_AUTOCOMMIT during...

[lhc/web/wiklou.git] / includes / libs / rdbms / loadbalancer / ILoadBalancer.php

diff --git a/includes/libs/rdbms/loadbalancer/ILoadBalancer.php b/includes/libs/rdbms/loadbalancer/ILoadBalancer.php
index ba0b4a0..b21da72 100644 (file)
--- a/includes/libs/rdbms/loadbalancer/ILoadBalancer.php
+++ b/includes/libs/rdbms/loadbalancer/ILoadBalancer.php
@@ -86,8 +86,8 @@ interface ILoadBalancer {
 
        /** @var string Domain specifier when no specific database needs to be selected */
        const DOMAIN_ANY = '';
-       /** @var bool The generic query group (bool gives b/c with 1.33 method signatures) */
-       const GROUP_GENERIC = false;
+       /** @var string The generic query group */
+       const GROUP_GENERIC = '';
 
        /** @var int DB handle should have DBO_TRX disabled and the caller will leave it as such */
        const CONN_TRX_AUTOCOMMIT = 1;
@@ -155,6 +155,18 @@ interface ILoadBalancer {
         */
        public function redefineLocalDomain( $domain );
 
+       /**
+        * Indicate whether the tables on this domain are only temporary tables for testing
+        *
+        * In "temporary tables mode", the ILoadBalancer::CONN_TRX_AUTOCOMMIT flag is ignored
+        *
+        * @param bool $value
+        * @param string $domain
+        * @return bool Whether "temporary tables mode" was active
+        * @since 1.34
+        */
+       public function setTempTablesOnlyMode( $value, $domain );
+
        /**
         * Get the server index of the reader connection for a given group
         *
@@ -167,8 +179,7 @@ interface ILoadBalancer {
         *
         * @param string|bool $group Query group or false for the generic group
         * @param string|bool $domain DB domain ID or false for the local domain
-        * @throws DBError If no live handle can be obtained
-        * @return bool|int|string
+        * @return int|bool Returns false if no live handle can be obtained
         */
        public function getReaderIndex( $group = false, $domain = false );
 
@@ -270,7 +281,7 @@ interface ILoadBalancer {
         * @see ILoadBalancer::getServerAttributes()
         *
         * @param int $i Server index (overrides $groups) or DB_MASTER/DB_REPLICA
-        * @param string[]|string $groups Query group(s) or [] to use the default group
+        * @param string[]|string $groups Query group(s) in preference order; [] for the default group
         * @param string|bool $domain DB domain ID or false for the local domain
         * @param int $flags Bitfield of CONN_* class constants
         *
@@ -326,7 +337,7 @@ interface ILoadBalancer {
         * @see ILoadBalancer::getConnection() for parameter information
         *
         * @param int $i Server index or DB_MASTER/DB_REPLICA
-        * @param string[]|string $groups Query group(s) or [] to use the default group
+        * @param string[]|string $groups Query group(s) in preference order; [] for the default group
         * @param string|bool $domain DB domain ID or false for the local domain
         * @param int $flags Bitfield of CONN_* class constants (e.g. CONN_TRX_AUTOCOMMIT)
         * @return DBConnRef
@@ -347,7 +358,7 @@ interface ILoadBalancer {
         * @see ILoadBalancer::getConnection() for parameter information
         *
         * @param int $i Server index or DB_MASTER/DB_REPLICA
-        * @param string[]|string $groups Query group(s) or [] to use the default group
+        * @param string[]|string $groups Query group(s) in preference order; [] for the default group
         * @param string|bool $domain DB domain ID or false for the local domain
         * @param int $flags Bitfield of CONN_* class constants (e.g. CONN_TRX_AUTOCOMMIT)
         * @return DBConnRef
@@ -369,7 +380,7 @@ interface ILoadBalancer {
         * @see ILoadBalancer::getConnection() for parameter information
         *
         * @param int $i Server index or DB_MASTER/DB_REPLICA
-        * @param string[]|string $groups Query group(s) or [] to use the default group
+        * @param string[]|string $groups Query group(s) in preference order; [] for the default group
         * @param string|bool $domain DB domain ID or false for the local domain
         * @param int $flags Bitfield of CONN_* class constants (e.g. CONN_TRX_AUTOCOMMIT)
         * @return MaintainableDBConnRef
@@ -455,11 +466,30 @@ interface ILoadBalancer {
        public function getServerAttributes( $i );
 
        /**
-        * Get the current master position for chronology control purposes
+        * Get the current master replication position
+        *
         * @return DBMasterPos|bool Returns false if not applicable
+        * @throws DBError
         */
        public function getMasterPos();
 
+       /**
+        * Get the highest DB replication position for chronology control purposes
+        *
+        * If there is only a master server then this returns false. If replication is present
+        * and correctly configured, then this returns the highest replication position of any
+        * server with an open connection. That position can later be passed to waitFor() on a
+        * new load balancer instance to make sure that queries on the new connections see data
+        * at least as up-to-date as queries (prior to this method call) on the old connections.
+        *
+        * This can be useful for implementing session consistency, where the session
+        * will be resumed accross multiple HTTP requests or CLI script instances.
+        *
+        * @return DBMasterPos|bool Replication position or false if not applicable
+        * @since 1.34
+        */
+       public function getReplicaResumePos();
+
        /**
         * Disable this load balancer. All connections are closed, and any attempt to
         * open a new connection will result in a DBAccessError.