From Qt Wiki
< QtWebEngine(Redirected from QtWebEngine/Proxies)
Jump to: navigation, search

Qt WebEngine uses the Chromium networking stack instead of Qt Network.

Proxy Resolution

Note: If the first page takes long too load, this is often because Qt WebEngine queries the network for a PAC (Proxy Auto-Configuration) file.

Proxy resolution in Qt Network

Qt Network has a various levels to set proxies for client connections (evaluated in this order):

  1. QAbstractSocket::setProxy
  2. QNetworkAccessManager::setProxy
  3. QNetworkAccessManager::setProxyFactory
  4. QNetworkProxy::setApplicationProxy
  5. QNetworkProxyFactory::setUseSystemConfiguration
  6. QNetworkProxyFactory::setApplicationProxyFactory

Since Qt 5.6, there's a default QNetworkProxyFactory::applicationProxyFactory that uses the system settings (see -system-proxies / -no-system-proxies configure flag).

Proxy resolution in Qt WebEngine

Qt WebEngine does not feature an API for setting proxies directly. Anyhow, it can

  1. Use the system proxy settings
  2. Use any proxy set explicitly in Qt Network

From Qt 5.8 onwards, The system proxy settings are used if QNetworkProxyFactory::usesSystemConfiguration returns true.

Otherwise Qt WebEngine adapts QNetworkProxy::applicationProxy . It does only use the following properties though:

Other settings in QNetworkProxy (or Qt Network in general) are ignored.

Note: The code path used to auto-detect proxy settings in the network differ, depending on whether --single-process is used. See https://codereview.qt-project.org/#/c/115567/ for details.

Proxy authentication

To authenticate proxies, connect to the QWebEnginePage::proxyAuthenticationRequired or WebEngineView::authenticationDialogRequested signal.