Made the SQLite installer make a separate objectcache DB

* This avoids severe lock contention if CACHE_DB is used and also makes
  cache sharing between wikis simple (keys are always prefixed as needed).

Bug: T89180
Change-Id: I864272af099a9ebe2b3648e2714d2ccdee20305d

diff --git a/includes/installer/SqliteInstaller.php b/includes/installer/SqliteInstaller.php
index 37fba15..1e7e969 100644 (file)
--- a/includes/installer/SqliteInstaller.php
+++ b/includes/installer/SqliteInstaller.php
@@ -226,6 +226,49 @@ class SqliteInstaller extends DatabaseInstaller {
                }
 
                $db = $this->getVar( 'wgDBname' );
+
+               # Make the main and cache stub DB files
+               $status = Status::newGood();
+               $status->merge( $this->makeStubDBFile( $dir, $db ) );
+               $status->merge( $this->makeStubDBFile( $dir, "wikicache" ) );
+               if ( !$status->isOK() ) {
+                       return $status;
+               }
+
+               # Nuke the unused settings for clarity
+               $this->setVar( 'wgDBserver', '' );
+               $this->setVar( 'wgDBuser', '' );
+               $this->setVar( 'wgDBpassword', '' );
+               $this->setupSchemaVars();
+
+               # Create the global cache DB
+               try {
+                       global $wgSQLiteDataDir;
+                       # @todo FIXME: setting globals kind of sucks
+                       $wgSQLiteDataDir = $dir;
+                       $conn = DatabaseBase::factory( 'sqlite', array( 'dbname' => "wikicache" ) );
+                       # @todo: don't duplicate objectcache definition, though it's very simple
+                       $sql =
+<<<EOT
+       CREATE TABLE IF NOT EXISTS objectcache (
+         keyname BLOB NOT NULL default '' PRIMARY KEY,
+         value BLOB,
+         exptime TEXT
+       )
+EOT;
+                       $conn->query( $sql );
+                       $conn->query( "CREATE INDEX IF NOT EXISTS exptime ON objectcache (exptime)" );
+                       $conn->query( "PRAGMA journal_mode=WAL" ); // this is permanent
+                       $conn->close();
+               } catch ( DBConnectionError $e ) {
+                       return Status::newFatal( 'config-sqlite-connection-error', $e->getMessage() );
+               }
+
+               # Open the main DB
+               return $this->getConnection();
+       }
+
+       protected function makeStubDBFile( $dir, $db ) {
                $file = DatabaseSqlite::generateFileName( $dir, $db );
                if ( file_exists( $file ) ) {
                        if ( !is_writable( $file ) ) {
@@ -236,13 +279,8 @@ class SqliteInstaller extends DatabaseInstaller {
                                return Status::newFatal( 'config-sqlite-cant-create-db', $file );
                        }
                }
-               // nuke the unused settings for clarity
-               $this->setVar( 'wgDBserver', '' );
-               $this->setVar( 'wgDBuser', '' );
-               $this->setVar( 'wgDBpassword', '' );
-               $this->setupSchemaVars();
 
-               return $this->getConnection();
+               return Status::newGood();
        }
 
        /**
@@ -280,6 +318,16 @@ class SqliteInstaller extends DatabaseInstaller {
                $dir = LocalSettingsGenerator::escapePhpString( $this->getVar( 'wgSQLiteDataDir' ) );
 
                return "# SQLite-specific settings
-\$wgSQLiteDataDir = \"{$dir}\";";
+\$wgSQLiteDataDir = \"{$dir}\";
+\$wgObjectCaches[CACHE_DB] = array(
+       'class' => 'SqlBagOStuff',
+       'loggroup' => 'SQLBagOStuff',
+       'server' => array(
+               'type' => 'sqlite',
+               'dbname' => 'wikicache',
+               'tablePrefix' => '',
+               'flags' => 0
+       )
+);";
        }
 }