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QNetworkReply and 301 Redirects

I have a web viewer and I want it to have access only to our web applications, for this I posted the php header that I am looking for in my Qt application. This works fine, but with one exception and with 301 permanent status codes. Modern browsers redirect you automatically, but put "/" at the end of the HTTP request.

When the URL of our web application is entered, it currently needs the trailing slash to be able to detect headers, but I want it to fall in that header too, even if they don't put the trailing slash.

Here is my current method for retrieving the header:

QNetworkAccessManager *manager = new QNetworkAccessManager(this);
    QNetworkRequest request;
    request.setUrl(url);
    connect(manager, SIGNAL(finished(QNetworkReply*)), this, SLOT(onFinished(QNetworkReply*)));

    request.setRawHeader("User-Agent", "CytoViewer 1.0");
    request.setHeader(QNetworkRequest::ContentTypeHeader,"application/CytoViewer");
    QNetworkReply *reply = manager->get(request);
    reply->ignoreSslErrors();
    QEventLoop loop;

    connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
    loop.exec();
    qDebug() << "QLoop reply all: " << reply->readAll();
    qDebug() << "QLoop: " << reply->rawHeader("Cyto-Study-Manager");
    if(reply->rawHeader("OurWebApp") == "1"){
        //Header exists?(QEventLoop finish) Set arg[1]"url 'Found prouct: product header'"
        product = reply->rawHeader("Product");
        return true;
    } else {
        //Header doen't exist? Graceful error - not a valid PI product
        return false;
    }

301 , : URL 301, 301, URL reply->attribute(QNetworkRequest::RedirectionTargetAttribute).toUrl(); URL , , URL, , .

, , :

QUrl MainWindow::networkRequest(QUrl checkUrl){
    qDebug() << "checkURL: " << checkUrl;
    //
    QNetworkAccessManager *manager = new QNetworkAccessManager(this);
    QNetworkRequest request;
    request.setUrl(checkUrl);
    request.setRawHeader("User-Agent", "CytoViewer 1.0");
    request.setHeader(QNetworkRequest::ContentTypeHeader,"application/CytoViewer");
    QNetworkReply *reply = manager->get(request);
    reply->ignoreSslErrors();
    QEventLoop checkLoop;
    connect(reply, SIGNAL(finished()), &checkLoop, SLOT(quit()));
    checkLoop.exec();
    //Check status code
    if (reply->error() == QNetworkReply::NoError) {
        int statusCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
        if(statusCode == 301) {
            QUrl redirectUrl = reply->attribute(QNetworkRequest::RedirectionTargetAttribute).toUrl();
            return redirectUrl;
        }else {
            return checkUrl;
        }

    }
}

, : 1) 301 2) .

? , ?

+7
2

-, .

HOWTO http://developer.nokia.com/community/wiki/Handling_an_HTTP_redirect_with_QNetworkAccessManager ( , )

:

void QNAMRedirect::replyFinished(QNetworkReply* reply) {
    /*
     * Reply is finished!
     * We'll ask for the reply about the Redirection attribute
     * http://doc.trolltech.com/qnetworkrequest.html#Attribute-enum
     */
    QVariant possibleRedirectUrl =
             reply->attribute(QNetworkRequest::RedirectionTargetAttribute);

    /* We'll deduct if the redirection is valid in the redirectUrl function */
    _urlRedirectedTo = this->redirectUrl(possibleRedirectUrl.toUrl(),
                                         _urlRedirectedTo);

    /* If the URL is not empty, we're being redirected. */
    if(!_urlRedirectedTo.isEmpty()) {
        QString text = QString("QNAMRedirect::replyFinished: Redirected to ")
                              .append(_urlRedirectedTo.toString());
        this->_textContainer->setText(text);

        /* We'll do another request to the redirection url. */
        this->_qnam->get(QNetworkRequest(_urlRedirectedTo));
    }
    else {
        /*
         * We weren't redirected anymore
         * so we arrived to the final destination...
         */
        QString text = QString("QNAMRedirect::replyFinished: Arrived to ")
                              .append(reply->url().toString());
        this->_textContainer->setText(text);
        /* ...so this can be cleared. */
        _urlRedirectedTo.clear();
    }
    /* Clean up. */
    reply->deleteLater();
}

QUrl QNAMRedirect::redirectUrl(const QUrl& possibleRedirectUrl,
                               const QUrl& oldRedirectUrl) const {
    QUrl redirectUrl;
    /*
     * Check if the URL is empty and
     * that we aren't being fooled into a infinite redirect loop.
     * We could also keep track of how many redirects we have been to
     * and set a limit to it, but we'll leave that to you.
     */
    if(!possibleRedirectUrl.isEmpty() &&
       possibleRedirectUrl != oldRedirectUrl) {
        redirectUrl = possibleRedirectUrl;
    }
    return redirectUrl;
}
+11

Qt 5.6 (QNetworkRequest::FollowRedirectsAttribute).

:

QNetworkRequest req(QUrl("https://example.com/"));
req.setAttribute(QNetworkRequest::FollowRedirectsAttribute, true);
+18

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