QHttpMultiPart generates different boundary

[wzj1695224]

When I try to upload files by QHttpMultiPart , there appears a problem. I use the CommonsMultipartResolver.isMultipart() to validate the request, and it returns false.

So I capture frame by Wireshark, and I found an interesting thing: the boundaries in the frame are all different.

Here is my client code

    QHttpMultiPart *multiPart = new QHttpMultiPart(QHttpMultiPart::FormDataType);

    QHttpPart zipPart;
    zipPart.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("application/zip"));
    zipPart.setHeader(QNetworkRequest::ContentDispositionHeader, QVariant("form-data; name=\"file\""));
    QFile *file = new QFile(pakPath);
    file->open(QIODevice::ReadOnly);
    zipPart.setBodyDevice(file);

    multiPart->append(zipPart);

    QNetworkRequest *request = new QNetworkRequest(QUrl(url));

    manager->put(*request, multiPart);

And the server code

    CommonsMultipartResolver(request.getSession().getServletContext()); 
    if( multipartResolver.isMultipart(request) ) {    // here return false
        ...

I have two questions:
Q1: Is the different boundary make itself be an abnormal in CommonsMultipartResolver?
Q2: Is Different boundary normal or Qt make mistake?

[raven-worx]

@wzj1695224
that's correct per definition

First the boundary is defined: "boundary_.oOo._MjMyNDk=MjMyNDk=MjA1MTM=MTI2Njc="
Then the (second) boundary denotes the beginning of the multipart data, by prefixing "--".
The end of the multipart data is then defined by prefixing and suffixing "--".