Using cache with QNetworkAccessManager

[remy_david]

Hi all,

I can't manage to make the cache work with WNAM.
Here is what I did so far :

MyNetworkManager* manager = new MyNetworkManager(parent);
    QNetworkDiskCache* diskCache = new QNetworkDiskCache(parent);
    QString dataPath = QDesktopServices::storageLocation(QDesktopServices::CacheLocation);
    diskCache->setCacheDirectory(dataPath);
    diskCache->setMaximumCacheSize(5*1024*1024); // 5Mo
    manager->setCache(diskCache);

MyNetworkManager* manager = new MyNetworkManager(parent);
    QNetworkDiskCache* diskCache = new QNetworkDiskCache(parent);
    QString dataPath = QDesktopServices::storageLocation(QDesktopServices::CacheLocation);
    diskCache->setCacheDirectory(dataPath);
    diskCache->setMaximumCacheSize(5*1024*1024); // 5Mo
    manager->setCache(diskCache);

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MyNetworkManager is very simple and redefines :

QNetworkReply *
MyNetworkManager::createRequest( Operation op, const QNetworkRequest & req, QIODevice * outgoingData)
{
    QNetworkRequest request(req);
    request.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::PreferCache);
    return QNetworkAccessManager::createRequest(op, request, outgoingData);
}

QNetworkReply *
MyNetworkManager::createRequest( Operation op, const QNetworkRequest & req, QIODevice * outgoingData)
{
    QNetworkRequest request(req);
    request.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::PreferCache);
    return QNetworkAccessManager::createRequest(op, request, outgoingData);
}

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I use this manager in a Symbian QML application. I can see all requests goes through my createRequest function, which is fine.
I can also see that .cache files are created in the cache directory and they contains the responses data.
However, when I switch the internet connection off, the manager does not return cached data.

What am I doing wrong here ? Can somebody point me on a working exemple of using cache with QNAM (preferably with QML but pure Qt is also ok).

Thank you for your help !

Rémy