New TomahawkCache utility class.

A simple, generic cache utility that various bits and bobs can use.

src/libtomahawk/CMakeLists.txt

@@ -291,6 +291,7 @@ set( libSources
     utils/logger.cpp
     utils/qnr_iodevicestream.cpp
     utils/xspfloader.cpp
+    utils/tomahawkcache.cpp
 
     thirdparty/kdsingleapplicationguard/kdsingleapplicationguard.cpp
     thirdparty/kdsingleapplicationguard/kdsharedmemorylocker.cpp

src/libtomahawk/utils/tomahawkcache.cpp

@@ -0,0 +1,140 @@
+/* === This file is part of Tomahawk Player - <http://tomahawk-player.org> ===
+ *
+ *   Copyright 2012, Casey Link <unnamedrambler@gmail.com>
+ *
+ *   Tomahawk is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   Tomahawk is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with Tomahawk. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "tomahawkcache.h"
+
+#include "tomahawksettings.h"
+
+#include <QDateTime>
+#include <QSettings>
+
+using namespace TomahawkUtils;
+
+TomahawkCache*TomahawkCache::s_instance = 0;
+
+TomahawkCache* TomahawkCache::instance()
+{
+    if ( !s_instance )
+        s_instance = new TomahawkCache();
+
+    return s_instance;
+}
+
+TomahawkCache::TomahawkCache()
+    : QObject ( 0 )
+    , m_cacheBaseDir ( TomahawkSettings::instance()->storageCacheLocation() + "/GenericCache/" )
+    , m_cacheManifest ( m_cacheBaseDir + "cachemanifest.ini", QSettings::IniFormat )
+{
+    m_pruneTimer.setInterval ( 300000 );
+    m_pruneTimer.setSingleShot ( false );
+    connect ( &m_pruneTimer, SIGNAL ( timeout() ), SLOT ( pruneTimerFired() ) );
+    m_pruneTimer.start();
+}
+
+TomahawkCache::~TomahawkCache()
+{
+
+}
+
+void TomahawkCache::pruneTimerFired()
+{
+    qDebug() << Q_FUNC_INFO << "Pruning tomahawkcache";
+    qlonglong currentMSecsSinceEpoch = QDateTime::currentMSecsSinceEpoch();
+
+    QVariantList clients = m_cacheManifest.value ( "clients" ).toList();
+    foreach ( const QVariant &client, clients ) {
+        const QString client_identifier = client.toString();
+        const QString cache_dir = m_cacheBaseDir + client_identifier;
+
+        QSettings cached_settings ( cache_dir, QSettings::IniFormat );
+        const QStringList keys = cached_settings.allKeys();
+        foreach ( const QString &key, keys ) {
+            CacheData data = cached_settings.value ( key ).value<TomahawkUtils::CacheData>();
+            if ( data.maxAge < currentMSecsSinceEpoch ) {
+                cached_settings.remove ( key );
+                tLog() << Q_FUNC_INFO << "Removed stale entry: " << client_identifier << key;
+            }
+        }
+        cached_settings.sync();
+        if ( cached_settings.allKeys().size() == 0 )
+            removeClient ( client_identifier );
+    }
+}
+
+
+QVariant TomahawkCache::getData ( const QString& identifier, const QString& key )
+{
+    const QString cacheDir = m_cacheBaseDir + identifier;
+    QSettings cached_settings ( cacheDir, QSettings::IniFormat );
+
+    if ( cached_settings.contains ( key ) ) {
+        CacheData data = cached_settings.value ( key ).value<TomahawkUtils::CacheData>();
+
+        if ( data.maxAge < QDateTime::currentMSecsSinceEpoch() ) {
+            cached_settings.remove ( key );
+            tLog() << Q_FUNC_INFO << "Removed stale entry: " << identifier << key;
+            return QVariant();
+        }
+        return data.data;
+
+    }
+    return QVariant();
+}
+
+void TomahawkCache::putData ( const QString& identifier, qint64 maxAge, const QString& key, const QVariant& value )
+{
+    const QString cacheDir = m_cacheBaseDir + identifier;
+    addClient ( identifier );
+    QSettings cached_settings ( cacheDir, QSettings::IniFormat );
+    cached_settings.setValue ( key, QVariant::fromValue ( CacheData ( maxAge, value ) ) );
+}
+
+void TomahawkCache::addClient ( const QString& identifier )
+{
+    QVariantList clients = m_cacheManifest.value ( "clients" ).toList();
+    foreach ( const QVariant &client, clients ) {
+        const QString client_identifier = client.toString();
+        if ( identifier == client_identifier ) return;
+    }
+
+    tLog() << Q_FUNC_INFO << "adding client" << identifier;
+    clients.append ( identifier );
+    m_cacheManifest.setValue ( "clients", clients );
+    m_cacheManifest.sync();
+}
+
+void TomahawkCache::removeClient ( const QString& identifier )
+{
+    QVariantList clients = m_cacheManifest.value ( "clients" ).toList();
+    QVariantList::iterator it = clients.begin();
+    while ( it != clients.end() ) {
+        const QString client_identifier = it->toString();
+        if ( identifier == client_identifier ) {
+            tLog() << Q_FUNC_INFO << "removing client" << identifier;
+            clients.erase ( it );
+            break;
+        }
+        ++it;
+    }
+    m_cacheManifest.setValue ( "clients", clients );
+    m_cacheManifest.sync();
+}
+
+
+
+

src/libtomahawk/utils/tomahawkcache.h

@@ -0,0 +1,72 @@
+/* === This file is part of Tomahawk Player - <http://tomahawk-player.org> ===
+ *
+ *   Copyright 2012, Casey Link <unnamedrambler@gmail.com>
+ *
+ *   Tomahawk is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   Tomahawk is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with Tomahawk. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef TOMAHAWKCACHE_H
+#define TOMAHAWKCACHE_H
+
+#include "dllmacro.h"
+#include "utils/tomahawkutils.h"
+
+#include <QSettings>
+#include <QObject>
+#include <QTimer>
+
+namespace TomahawkUtils {
+
+struct CacheData {
+    CacheData(){}
+    CacheData( qint64 maxAg, QVariant dat )
+    : maxAge( maxAg )
+    , data( dat )
+    {}
+
+    qint64 maxAge;
+    QVariant data;
+};
+
+class DLLEXPORT TomahawkCache : public QObject
+{
+Q_OBJECT
+
+public:
+    static TomahawkCache* instance();
+    virtual ~TomahawkCache();
+
+    void putData( const QString &identifier, qint64 maxAge, const QString &key, const QVariant& value );
+    QVariant getData( const QString &identifier, const QString &key );
+
+private slots:
+    void pruneTimerFired();
+
+private:
+    TomahawkCache();
+    static TomahawkCache* s_instance;
+
+    void addClient( const QString &identifier );
+    void removeClient( const QString &identifier );
+
+    QString m_cacheBaseDir;
+    QSettings m_cacheManifest;
+    QTimer m_pruneTimer;
+};
+
+}
+
+Q_DECLARE_METATYPE( TomahawkUtils::CacheData );
+
+#endif // TOMAHAWKCACHE_H

src/tomahawkapp.cpp

@@ -62,6 +62,7 @@
 #include "utils/jspfloader.h"
 #include "utils/logger.h"
 #include "utils/tomahawkutilsgui.h"
+#include "utils/tomahawkcache.h"
 
 #include "config.h"
 
@@ -228,7 +229,7 @@ TomahawkApp::init()
     tDebug() << "Init AccountManager.";
     m_accountManager = QWeakPointer< Tomahawk::Accounts::AccountManager >( new Tomahawk::Accounts::AccountManager( this ) );
     connect( m_accountManager.data(), SIGNAL( ready() ), SLOT( accountManagerReady() ) );
-    
+
     Echonest::Config::instance()->setNetworkAccessManager( TomahawkUtils::nam() );
 #ifndef ENABLE_HEADLESS
     EchonestGenerator::setupCatalogs();
@@ -318,6 +319,7 @@ TomahawkApp::~TomahawkApp()
         delete m_audioEngine.data();
 
     delete Tomahawk::Accounts::AccountManager::instance();
+    delete TomahawkUtils::TomahawkCache::instance();
 
 #ifndef ENABLE_HEADLESS
     delete m_mainwindow;
@@ -449,6 +451,9 @@ TomahawkApp::registerMetaTypes()
     qRegisterMetaType< QPersistentModelIndex >( "QPersistentModelIndex" );
 
     qRegisterMetaType< Tomahawk::PlaylistInterface::LatchMode >( "Tomahawk::PlaylistInterface::LatchMode" );
+
+    qRegisterMetaType< TomahawkUtils::CacheData>( "TomahawkUtils::CacheData" );
+
 }