[Solved] QNetworkAccessManager empy reply next get fails

LuGRU

Hello,
I have a strange problem.
I want to download XML (with is result of query from WWW) and situation looks like this:

1st GET() request always success
next request do success when previous reply data is not empty
next request do FAIL when previous data is empty

By fail I mean nothing happens at all. Checked with Wireshark and no GET request is send to WWW so Qt just fall-back silently (no finished(), progress() etc is emited, dead silence on QNetworkReply / QNetworkAccessManager).

WWW uses basic authentication, on first connect attempt I do recive authenticationRequired(QNetworkReply*,QAuthenticator*) signal and after authentication everything works fine as long as server do reply with data.

I'm open to any suggestion.
NOTE: code is ok, because every other WWW do reply correctly so it seams to me that it's Qt bug similar to this one: https://bugreports.qt.io/browse/QTBUG-5997

Thanks in advance for reply.
Best regards

UPDATE:
More info about situation:

QNetworkAccessManager GET -> finished() -> reply->readAll() NOT empty
QNetworkAccessManager GET -> finished() -> reply->readAll() NOT empty
...
QNetworkAccessManager GET -> finished() -> reply->readAll() IS empty
QNetworkAccessManager GET -> dead silence nothing happens at this point using reply->abort(); reply->close() nothing works. No finished() / progress() etc.

LuGRU

In free time I did more research and server reply with HTTP status 204. After receiving 204 next GET request does nothing.

Update:
situation 1
QNetworkAccessManager ->get() ... reply HTTP 200
QNetworkAccessManager ->get() ... reply HTTP 204
QNetworkAccessManager ->get() ... nothing

situation 2
QNetworkAccessManager ->get() ... reply HTTP 204
QNetworkAccessManager ->get() ... nothing

So when QNetworkAccessManager get 204 next get() will fail.

LuGRU

Solution:
There is something wrong with QNetworkAccessManager when HTTP 204 reply ("No content") is received. Probably timeout or internal connection state is not updated (i.e. class still thinks that connection / reply did not finished).

To get around this don't use persistent connection Keep-alive but close each time.

    QNetworkRequest request;
    request.setUrl( url);
    ...
    request.setRawHeader("Connection", "close");