QWebKit Setting Up User Agent

[anshah]

My application uses QWebKit on Ubuntu Linux. I need to setup a User Agent with a prefix and then add an emulated browser agent string.

I figured out how to setup the User Agent by overloading QWebPage::userAgentForUrl. I have the User Agent prefix setup already but now I want to add the emulated browser agent string to this prefix.

I found that in MAC using WebKit::WebView the emulated browser agent is setup by the following:

WebView myWebView;
...
NSString *uagnt = [myWebView stringByEvaluatingJavaScriptFromString:@"navigator.userAgent"];

I know the QWebKit uses WebKit as a backend so this must be possible in Qt WebKit. How can I go about doing this in QWebView / QWebPage?

[SGaist]

Hi,

From the looks of it, you can create a QWebPage subclass and re-implement QWebPage::userAgentForUrl.

Hope it helps

[anshah]

@sgaist Thanks for the reply! I have already created a subclass and reimplemented QWebPage::userAgentForUrl so I got that part covered.

The main question I had was what is the Qt equivalent of:

WebView:stringByEvaluatingJavaScriptFromString

In Qt is there a way I can extract the "navigator.userAgent" JavaScript as seen in this code example using WebView on MAC:

WebView myWebView;
...
NSString *uagnt = [myWebView stringByEvaluatingJavaScriptFromString:@"navigator.userAgent"];

[SGaist]

I may have misunderstood your problem.

Can you detail a bit more what you want to do with that information and where you would like to extract it ?

[anshah]

@sgaist Sorry I should have been more clear to begin with. Basically all I want to do is extract the following string in QtWebKit by evaluating JavaScript:

navigator.userAgent

I want to set up our user agent with a predefined prefix plus the JavaScript evaluated "navigator.userAgent".

So I have already subclassed QWebPage::userAgentForUrl and have the prefix set. Now the last piece of the puzzle is adding "navigator.userAgent" by evaluating JavaScript.

I need to do this for SAML authentication testing.

As I illustrated before in MAC this is done by:

WebView myWebView;
...
NSString *uagnt = [myWebView stringByEvaluatingJavaScriptFromString:@"navigator.userAgent"];

How can I achieve this in QtWebKit? Do I achieve this using QWebView, QWebPage, or QWebFrame?

Hope I was clearer this time around.

[Konstantin Tokarev]

Evaluating navigator.userAgent returns whatever string is returned by QWebPage::userAgentForUrl. If you want to evaluate arbitrary JS expressions, use QWebFrame::evaluateJavaScript

[anshah]

@konstantin-tokarev
@SGaist
Is there a way to get the parent's userAgentForUrl value? Such as below?

// User Agent Web Page
class UserAgentWebPage : public QWebPage
{
    QString userAgentForUrl(const QUrl &url) const
    {
        // UserAgent: Prefix
        QString userAgent = QWebPage::userAgentForUrl();

        // Modify userAgent with custom prefixes

        return userAgent;
    }
};

My objective is to first obtain QtWebKit's User-Agent and then prefix that with my own custom fields.

So let me summarize my questions:

1. How do I obtain the default browser User-Agent string using QtWebKit?

2. How can I call QWebPage::userAgentForUrl() from it's child?

Any help would be most appreciated guys as I'm at a roadblock at the moment.

[Konstantin Tokarev]

Is there a way to get the parent's userAgentForUrl value? Such as below?

Yes it's possible

[Konstantin Tokarev]

However it might be enough for your purposes to set application name and version on your QApplication, this information will be displayed in UA string