* DatabaseCommands can now be marked "singleton-commands", which means that only the latest enqueued command of this type will be kept in the oplog.

src/libtomahawk/database/databasecommand.h

@@ -54,6 +54,7 @@ public:
     const Tomahawk::source_ptr& source() const { return m_source; }
 
     virtual bool loggable() const { return false; }
+    virtual bool singletonCmd() const { return false; }
 
     QString guid() const
     {

src/libtomahawk/database/databasecommand_logplayback.h

@@ -43,9 +43,11 @@ public:
     virtual QString commandname() const { return "logplayback"; }
 
     virtual void exec( DatabaseImpl* );
-    virtual bool doesMutates() const { return true; }
     virtual void postCommitHook();
 
+    virtual bool doesMutates() const { return true; }
+    virtual bool singletonCmd() const { return ( m_action == Started ); }
+
     QString artist() const { return m_artist; }
     void setArtist( const QString& s ) { m_artist = s; }
 

src/libtomahawk/database/databasecommandloggable.cpp

@@ -1,33 +1,3 @@
 #include "databasecommandloggable.h"
 
-#include <QDebug>
 
-#include "database/databasecommand_addfiles.h"
-#include "database/databasecommand_setplaylistrevision.h"
-
-
-DatabaseCommandLoggable*
-DatabaseCommandLoggable::factory( const QVariantMap& c )
-{
-    const QString name = c.value( "command" ).toString();
-    //TODO dynamic class loading, factory blah
-
-    if( name == "addfiles" )
-    {
-        DatabaseCommand_AddFiles* cmd = new DatabaseCommand_AddFiles;
-        QJson::QObjectHelper::qvariant2qobject( c, cmd );
-        return cmd;
-    }
-    else if( name == "setplaylistrevision" )
-    {
-        DatabaseCommand_SetPlaylistRevision* cmd = new DatabaseCommand_SetPlaylistRevision;
-        QJson::QObjectHelper::qvariant2qobject( c, cmd );
-        return cmd;
-    }
-    else
-    {
-        qDebug() << "Unhandled command name";
-        Q_ASSERT( false );
-        return 0;
-    }
-}

src/libtomahawk/database/databasecommandloggable.h

@@ -23,9 +23,6 @@ public:
     {}
 
     virtual bool loggable() const { return true; }
-
-    static DatabaseCommandLoggable* factory( const QVariantMap& c );
-
 };
 
 #endif // DATABASECOMMANDLOGGABLE_H

src/libtomahawk/database/databaseimpl.cpp

@@ -15,7 +15,7 @@
 */
 #include "schema.sql.h"
 
-#define CURRENT_SCHEMA_VERSION 15
+#define CURRENT_SCHEMA_VERSION 16
 
 
 DatabaseImpl::DatabaseImpl( const QString& dbname, Database* parent )

src/libtomahawk/database/databaseworker.cpp

@@ -156,8 +156,12 @@ void
 DatabaseWorker::logOp( DatabaseCommandLoggable* command )
 {
     TomahawkSqlQuery oplogquery = m_dbimpl->newquery();
-    oplogquery.prepare( "INSERT INTO oplog(source, guid, command, compressed, json) "
+    TomahawkSqlQuery oplogdelquery = m_dbimpl->newquery();
-                        "VALUES(?, ?, ?, ?, ?) ");
+
+    oplogquery.prepare( "INSERT INTO oplog(source, guid, command, singleton, compressed, json) "
+                        "VALUES(?, ?, ?, ?, ?, ?)" );
+    oplogdelquery.prepare( QString( "DELETE FROM oplog WHERE source %1 AND singleton = 'true' AND command = ?" )
+                              .arg( command->source()->isLocal() ? "IS NULL" : QString( "= %1" ).arg( command->source()->id() ) ) );
 
     QVariantMap variant = QJson::QObjectHelper::qobject2qvariant( command );
     QByteArray ba = m_serializer.serialize( variant );
@@ -176,6 +180,13 @@ DatabaseWorker::logOp( DatabaseCommandLoggable* command )
         //qDebug() << "Compressed DB OP JSON size:" << ba.length();
     }
 
+    if ( command->singletonCmd() )
+    {
+        qDebug() << "Singleton command, deleting previous oplog commands";
+        oplogdelquery.bindValue( 0, command->commandname() );
+        oplogdelquery.exec();
+    }
+
     qDebug() << "Saving to oplog:" << command->commandname()
              << "bytes:" << ba.length()
              << "guid:" << command->guid();
@@ -184,8 +195,9 @@ DatabaseWorker::logOp( DatabaseCommandLoggable* command )
                           QVariant(QVariant::Int) : command->source()->id() );
     oplogquery.bindValue( 1, command->guid() );
     oplogquery.bindValue( 2, command->commandname() );
-    oplogquery.bindValue( 3, compressed );
+    oplogquery.bindValue( 3, command->singletonCmd() );
-    oplogquery.bindValue( 4, ba );
+    oplogquery.bindValue( 4, compressed );
+    oplogquery.bindValue( 5, ba );
     if( !oplogquery.exec() )
     {
         qDebug() << "Error saving to oplog";

src/libtomahawk/database/schema.sql

@@ -7,6 +7,7 @@ CREATE TABLE IF NOT EXISTS oplog (
     source INTEGER REFERENCES source(id) ON DELETE CASCADE ON UPDATE CASCADE, -- DEFERRABLE INITIALLY DEFERRED,
     guid TEXT NOT NULL,
     command TEXT NOT NULL,
+    singleton BOOLEAN NOT NULL,
     compressed BOOLEAN NOT NULL,
     json TEXT NOT NULL
 );
@@ -228,4 +229,4 @@ CREATE TABLE IF NOT EXISTS settings (
     k TEXT NOT NULL PRIMARY KEY,
     v TEXT NOT NULL DEFAULT ''
 );
-INSERT INTO settings(k,v) VALUES('schema_version', '15');
+INSERT INTO settings(k,v) VALUES('schema_version', '16');

src/libtomahawk/database/schema.sql.h

@@ -1,5 +1,5 @@
 /*
-    This file was automatically generated from schema.sql on Tue Jan  4 06:55:23 CET 2011.
+    This file was automatically generated from schema.sql on Thu Jan  6 09:52:57 CET 2011.
 */
 
 static const char * tomahawk_schema_sql = 
@@ -8,6 +8,7 @@ static const char * tomahawk_schema_sql =
 "    source INTEGER REFERENCES source(id) ON DELETE CASCADE ON UPDATE CASCADE, "
 "    guid TEXT NOT NULL,"
 "    command TEXT NOT NULL,"
+"    singleton BOOLEAN NOT NULL,"
 "    compressed BOOLEAN NOT NULL,"
 "    json TEXT NOT NULL"
 ");"
@@ -161,7 +162,7 @@ static const char * tomahawk_schema_sql =
 "    k TEXT NOT NULL PRIMARY KEY,"
 "    v TEXT NOT NULL DEFAULT ''"
 ");"
-"INSERT INTO settings(k,v) VALUES('schema_version', '15');"
+"INSERT INTO settings(k,v) VALUES('schema_version', '16');"
     ;
 
 const char * get_tomahawk_sql()