Qt POST

    QFile file("/path/file.jpg");
    if(file.open(QIODevice::ReadOnly))
    {
        QUrl url("http://localhost:8888");

        QNetworkRequest request;
        request.setUrl(url);

        QHttpMultiPart multipart(QHttpMultiPart::FormDataType);

        QHttpPart image;
        image.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("multipart/form-data"));
        image.setHeader(QNetworkRequest::ContentLengthHeader, QVariant(file.size()));
        image.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("name=\"image\"; filename=\"name.jpg\""));
        image.setBodyDevice(&file);

        multipart.append(image);

        QNetworkReply *reply = manager->post(request, &multipart);

        QEventLoop wait;
        connect(reply, &QNetworkReply::finished, [&](){
            if(reply->error() == QNetworkReply::NoError)
                qDebug() << reply->readAll();

            reply->deleteLater();
            wait.quit();

        });
        wait.exec();
    }
    file.close();