QNetworkAccessManager and HTTP persistent connection

4
votes

HTTP 1.1 supports persistent connection by default, so I want to send my a second http request using the same connection that was setup when the first HTTP request was made. how can this be achieved through Qt?

If I simply make the second request after the first one finished like the following 

manager->get(QNetworkRequest(QUrl("http://qt-project.org")));

it seems a new TCP connection to the server will be initiated (I have checked with a network sniffer) The experiment also says: If the reply is deleteLater() or abort() within finished() signal, the connection will be closed.

1
qtqt4pyqtpyqt4pyside
You are showing C++ code yet "pyqqt pyqt4 pyside" are included in the tags. Please provide an reproducible code sample; it is possible that the persistent connection setting is not being set correctly. - Ramchandra Apte

1 Answers

1
votes

You can do the following to investigate further:

  • Dump the HTTP headers (known and raw) of the outgoing request. You should see a Connection: Keep-Alive header set.
  • Dump the response headers. There should not be a Connection: Close set by the webserver

Sometimes webservers don't honor the keep-alive header and will send a close anyway. In this case the client is rightfully closing the connection.