Rename DB_SLAVE constant to DB_REPLICA

[lhc/web/wiklou.git] / maintenance / Maintenance.php

diff --git a/maintenance/Maintenance.php b/maintenance/Maintenance.php
index 27d8161..6aa14b8 100644 (file)
--- a/maintenance/Maintenance.php
+++ b/maintenance/Maintenance.php
@@ -37,6 +37,7 @@ define( 'DO_MAINTENANCE', RUN_MAINTENANCE_IF_MAIN ); // original name, harmless
 $maintClass = false;
 
 use MediaWiki\Logger\LoggerFactory;
+use MediaWiki\MediaWikiServices;
 
 /**
  * Abstract maintenance class for quickly writing and churning out
@@ -123,6 +124,12 @@ abstract class Maintenance {
         */
        private $config;
 
+       /**
+        * @see Maintenance::requireExtension
+        * @var array
+        */
+       private $requiredExtensions = [];
+
        /**
         * Used to read the options in the order they were passed.
         * Useful for option chaining (Ex. dumpBackup.php). It will
@@ -506,6 +513,82 @@ abstract class Maintenance {
                $this->config = $config;
        }
 
+       /**
+        * Indicate that the specified extension must be
+        * loaded before the script can run.
+        *
+        * This *must* be called in the constructor.
+        *
+        * @since 1.28
+        * @param string $name
+        */
+       protected function requireExtension( $name ) {
+               $this->requiredExtensions[] = $name;
+       }
+
+       /**
+        * Verify that the required extensions are installed
+        *
+        * @since 1.28
+        */
+       public function checkRequiredExtensions() {
+               $registry = ExtensionRegistry::getInstance();
+               $missing = [];
+               foreach ( $this->requiredExtensions as $name ) {
+                       if ( !$registry->isLoaded( $name ) ) {
+                               $missing[] = $name;
+                       }
+               }
+
+               if ( $missing ) {
+                       $joined = implode( ', ', $missing );
+                       $msg = "The following extensions are required to be installed "
+                               . "for this script to run: $joined. Please enable them and then try again.";
+                       $this->error( $msg, 1 );
+               }
+
+       }
+
+       /**
+        * Set triggers like when to try to run deferred updates
+        * @since 1.28
+        */
+       public function setTriggers() {
+               $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
+               self::setLBFactoryTriggers( $lbFactory );
+       }
+
+       /**
+        * @param LBFactory $LBFactory
+        * @since 1.28
+        */
+       public static function setLBFactoryTriggers( LBFactory $LBFactory ) {
+               // Hook into period lag checks which often happen in long-running scripts
+               $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
+               $lbFactory->setWaitForReplicationListener(
+                       __METHOD__,
+                       function () {
+                               global $wgCommandLineMode;
+                               // Check config in case of JobRunner and unit tests
+                               if ( $wgCommandLineMode ) {
+                                       DeferredUpdates::tryOpportunisticExecute( 'run' );
+                               }
+                       }
+               );
+               // Check for other windows to run them. A script may read or do a few writes
+               // to the master but mostly be writing to something else, like a file store.
+               $lbFactory->getMainLB()->setTransactionListener(
+                       __METHOD__,
+                       function ( $trigger ) {
+                               global $wgCommandLineMode;
+                               // Check config in case of JobRunner and unit tests
+                               if ( $wgCommandLineMode && $trigger === IDatabase::TRIGGER_COMMIT ) {
+                                       DeferredUpdates::tryOpportunisticExecute( 'run' );
+                               }
+                       }
+               );
+       }
+
        /**
         * Run a child maintenance script. Pass all of the current arguments
         * to it.
@@ -865,7 +948,7 @@ abstract class Maintenance {
 
                // Description ...
                if ( $this->mDescription ) {
-                       $this->output( "\n" . $this->mDescription . "\n" );
+                       $this->output( "\n" . wordwrap( $this->mDescription, $screenWidth ) . "\n" );
                }
                $output = "\nUsage: php " . basename( $this->mSelf );
 
@@ -1144,7 +1227,7 @@ abstract class Maintenance {
         * If not set, wfGetDB() will be used.
         * This function has the same parameters as wfGetDB()
         *
-        * @param integer $db DB index (DB_SLAVE/DB_MASTER)
+        * @param integer $db DB index (DB_REPLICA/DB_MASTER)
         * @param array $groups; default: empty array
         * @param string|bool $wiki; default: current wiki
         * @return IDatabase
@@ -1181,14 +1264,14 @@ abstract class Maintenance {
        }
 
        /**
-        * Commit the transcation on a DB handle and wait for slaves to catch up
+        * Commit the transcation on a DB handle and wait for replica DBs to catch up
         *
         * This method makes it clear that commit() is called from a maintenance script,
         * which has outermost scope. This is safe, unlike $dbw->commit() called in other places.
         *
         * @param IDatabase $dbw
         * @param string $fname Caller name
-        * @return bool Whether the slave wait succeeded
+        * @return bool Whether the replica DB wait succeeded
         * @since 1.27
         */
        protected function commitTransaction( IDatabase $dbw, $fname ) {