Uploading files via HTTP/POST using QHttpMultiPart, no longer working

GregB

I have an application that uploads files to an http server. The application was working correctly until I upgraded the Qt version from 5.5.0 to 5.5.1.

Basically, after doing the networkmanager->post() operation, it never receives signals (finished, error, uploadprogress). So my application just waits for the signals which never come.

I have other form submission in my application which doesn't submit files, but those work just fine. I submit the form, and either the finished or error signals get called.

This is the abbreviated code for my file upload, which used to work, but now doesn't

QUrl url(connServer + "/api.php");
QNetworkRequest request(url);
QHttpMultiPart *multiPart = new QHttpMultiPart(QHttpMultiPart::FormDataType);
QHttpPart loginPart;
/* username */
loginPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"u\""));
loginPart.setBody(connUsername.toLatin1());
multiPart->append(loginPart);
/* password */
loginPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"p\""));
loginPart.setBody(connPassword.toLatin1());
multiPart->append(loginPart);
/* loop through the list of files */
ui->progUpload->setRange(0,100);
for (int i=0;i<list.size();i++) {
	QFile *file = new QFile(list[i]);
	QHttpPart filePart;
	filePart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"files[]\"; filename=\""+ file->fileName() + "\""));

	file->open(QIODevice::ReadOnly);
	filePart.setBodyDevice(file);
	file->setParent(multiPart); // we cannot delete the file now, so delete it with the multiPart
	multiPart->append(filePart);
}

while (isUploading) {
	ui->lblStatus->setText("Waiting for response from server");
	QTest::qWait(1000);
}
QNetworkReply* reply = networkManager->post(request, multiPart);
multiPart->setParent(reply); // delete the multiPart with the reply
connect(reply, SIGNAL(finished()), this, SLOT(onGetReplyUpload()));
connect(reply, SIGNAL(error(QNetworkReply::NetworkError)), this, SLOT(onNetworkError(QNetworkReply::NetworkError)));
connect(reply, SIGNAL(uploadProgress(qint64, qint64)), SLOT(progressChanged(qint64, qint64)));

This doesn't submit files with the form, and it still works fine:

QUrl url(connServer + "/api.php");
QNetworkRequest request(url);
QHttpMultiPart *multiPart = new QHttpMultiPart(QHttpMultiPart::FormDataType);
QHttpPart loginPart;
/* username */
loginPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"u\""));
loginPart.setBody(connUsername.toLatin1()); multiPart->append(loginPart);
/* password */
loginPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"p\""));
loginPart.setBody(connPassword.toLatin1()); multiPart->append(loginPart);
/* action */
loginPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"action\""));
loginPart.setBody("startTransaction"); multiPart->append(loginPart);
QNetworkReply* reply = networkManager->post(request, multiPart);
multiPart->setParent(reply); // delete the multiPart with the reply
connect(reply, SIGNAL(finished()), this, SLOT(onGetReplyStartTransaction()));

GregB

Figured out more details: The problem only occurs on Windows 10, and is not related to the Qt version.

SGaist

Hi and welcome to devnet,

Can you check if that still happens with Qt 5.6 Beta ?