[SOLVED] QFtp to get QStringList of remote files

i92guboj

Hi.

I am about to get mad on this one, so, please, just bear with me.

I really have no idea why QFtp is so complicated and I am about giving up and turning to any of the regular c or c++ libs, that just work (tm). But, anyway...

What I've done, so far, is as follows.

In my constructor, I am initializing the ftp connection like this:

@
///
/// FTP stuff
///

ftp = new QFtp;
ftp->connectToHost("moo.cow");
ftp->setTransferMode(QFtp::Passive);
ftp->login("foo", "bar");
ftp->cd(QString("/"));
lista_archivos_ftp = new QStringList;
ftp->list("/*.jpg");

//ftp.cd("img_art");

connect(ftp, SIGNAL(dataTransferProgress(qint64, qint64)),
        this, SLOT(my_gestor_progreso(qint64, qint64)));

connect(ftp, SIGNAL(commandStarted(int)),
        this, SLOT(my_empieza_comando_ftp(int)));

connect(ftp, SIGNAL(commandFinished(int,bool)),
        this, SLOT(my_acaba_comando_ftp(int,bool)));

connect(ftp, SIGNAL(done(bool)),
        this, SLOT(my_hecho_ftp(bool)));

connect(ftp, SIGNAL(stateChanged(int)),
        this, SLOT(my_estado_cambiado_ftp(int)));

connect(ftp, SIGNAL(listInfo(QUrlInfo)),
        this, SLOT(my_list_list_ftp(QUrlInfo)));

@

I don't think it's necessary to paste all the connected code, so I'll just show you the relevant bits (just ask if you need anything more).

@
void kooker::my_list_list_ftp(QUrlInfo url)
{
my_print_log(QString(Q_FUNC_INFO).append(url.name()));
lista_archivos_ftp->append(url.name());
}

void kooker::my_acaba_comando_ftp(int comando, bool error)
{
if(error)
{
my_print_log(QString("Comando FTP %1 devolvió error: %2")
.arg(comando)
.arg(ftp->errorString()));
}
else
{
my_print_log(QString("Comando FTP %1 se completó sin errores.")
.arg(comando));

    int c = ftp->currentCommand();
    if(ftp->currentCommand() == QFtp::List)
        on_btn_descargar_clicked();
}

}

void kooker::on_btn_descargar_clicked()
{
QEventLoop loop;
connect(ftp, SIGNAL(commandFinished(int,bool)),
&loop, SLOT(quit()));

QString item;
foreach(item, *lista_archivos_ftp)
{
    QString img_local_path = QString(photoDir->path().append("/%1").arg(item));
    QFile *file = new QFile&#40;img_local_path&#41;;

    if(!file->open(QIODevice::WriteOnly&#41;&#41;
    {
        delete file;
        return;
    }

    QString ftp_file = QString("/%1"&#41;.arg(item&#41;;
    ftp->get(ftp_file, file&#41;;
    loop.exec&#40;&#41;;

    file->close(&#41;;
}

}
@

The thing seems to eternally hang on the loop, and never go further, a single file (since the loop doesn't go on) is created, with zero length.

I have also tried to put file->close() in the slot called when commandFinished(), but it doesn't really work. This same on_btn_descargar_clicked() slot works without a flaw when I click the relevant button. But that's not really an option. This must be done automatically, without user interaction.

I suspect this silly QFtp stuff is blocking the signals, that would explain why the loop never ends when I call the function from inside one of the QFtp member functions (commandFinished()). I have no idea how to check that the Get command has ended for a given file, so I can close the damn file and save it adequately. This is all my own inference, so I might very well be completely wrong in everything I exposed.

However, while researching on this during the past few days I've found that they are ditching down QFtp in qt5, so I think I am not the only QFtp hater out there. Is there any other relevant alternative in the Qt world? What's your advice on this if I want to continue maintaining this for a long time? I don't want to waste any more time than necessary on this if in one or two years I will be having to rewrite this using libcurl anyway...

Thanks for reading. Any tip is welcome :(

POSTDATA:
I forgot, I also tried the loop-less version, like this

@
void kooker::my_acaba_comando_ftp(int comando, bool error)
{
if(error)
{
my_print_log(QString("Comando FTP %1 devolvió error: %2")
.arg(comando)
.arg(ftp->errorString()));
}
else
{
my_print_log(QString("Comando FTP %1 se completó sin errores.")
.arg(comando));

    int c = ftp->currentCommand();
    if(ftp->currentCommand() == QFtp::List)
        on_btn_descargar_clicked();

    if(ftp->currentCommand() == QFtp::Get)
        ftp_local_file->close();
}

}

void kooker::on_btn_descargar_clicked()
{
//QEventLoop loop;

//connect(ftp, SIGNAL(commandFinished(int,bool)),
//        &loop, SLOT(quit()));

QString item;
foreach(item, *lista_archivos_ftp)
{
    QString img_local_path = QString(photoDir->path().append("/%1").arg(item));
    //QFile *file = new QFile&#40;img_local_path&#41;;
    ftp_local_file = new QFile(img_local_path&#41;;

    if(!ftp_local_file->open(QIODevice::WriteOnly&#41;&#41;
    {
        delete ftp_local_file;
        return;
    }

    QString ftp_file = QString("/%1"&#41;.arg(item);
    ftp->get(ftp_file, ftp_local_file);
    //loop.exec(&#41;;

    //file->close(&#41;;
}

}
@

In this case, it doesn't block, ALL the files are created in the local folder, but, the files are still empty.

i92guboj

It only took me one week to figure this one out, so I'll better post it here for future reference.

Ripping out the loop seemed to work.

@void kooker::fetchFtpList()
{
qDebug() << Q_FUNC_INFO << "Entering...";
if(!ftp_file_list->isEmpty())
{
QString item = ftp_file_list->takeFirst();
QString img_local_path = QString(photoDir->path().append("/%1").arg(item));
ftp_local_file = new QFile(img_local_path);

    if(!ftp_local_file->open(QIODevice::WriteOnly&#41;)
    {
        delete ftp_local_file;
        return;
    }

    QString ftp_file = QString("/%1").arg(item);
    ftp->get(ftp_file, ftp_local_file);
}
//}

}

void kooker::my_commandFinished(int command, bool error)
{
if(error)
{
qDebug() << QString("FTP command %1 returned: '%2'")
.arg(command)
.arg(ftp->errorString());
}
else
{
if(ftp->currentCommand() == QFtp::List)
fetchFtpList();

    if(ftp->currentCommand() == QFtp::Get)
    {
        qDebug() << Q_FUNC_INFO << QString("closing file associated with command %1, %2 bytes")
                    .arg(command)
                    .arg(ftp_local_file->size());
        ftp_local_file->close();
        fetchFtpList();
    }
}

}@