mechanize (python) click on a javascript type link

Question

is it possible to have mechanize follow an anchor link that is of type javascript?

I am trying to login into a website in python using mechanize and beautifulsoup.

this is the anchor link

<a id="StaticModuleID15_ctl00_SkinLogin1_Login1_Login1_LoginButton" href="javascript:WebForm_DoPostBackWithOptions(new WebForm_PostBackOptions(&quot;StaticModuleID15$ctl00$SkinLogin1$Login1$Login1$LoginButton&quot;, &quot;&quot;, true, &quot;Login1&quot;, &quot;&quot;, false, true))"><img id="StaticModuleID15_ctl00_SkinLogin1_Login1_Login1_Image2" border="0" src="../../App_Themes/default/images/Member/btn_loginenter.gif" align="absmiddle" style="border-width:0px;" /></a>

and here is what i have tried

    links = SoupStrainer('a', id="StaticModuleID15_ctl00_SkinLogin1_Login1_Login1_LoginButton")
    [anchor for anchor in BeautifulSoup(data, parseOnlyThese=links)]
    link = mechanize.Link( base_url = self.url,
                    url = str(anchor['href']),
                    text = str(anchor.string),
                    tag = str(anchor.name),
                    attrs = [(str(name), str(value))
                             for name, value in anchor.attrs])
    response2 = br.follow_link(link)

Right now I am getting the error message of,

urllib2.URLError:

any help or suggestion is appreciated

Edit

After the comment by helpers, I went and looked at the code of the asp page a bit.

I found a little bit of useful scripts but I am unsure of what I have to do in python to emulate the JS code with python. In no where did I see any cookies set, am I looking at the wrong places?

<form name="form1" method="post" action="BrowseSchedule.aspx?ItemId=75" onsubmit="javascript:return WebForm_OnSubmit();" id="form1">

//<![CDATA[
function WebForm_OnSubmit() {
if (typeof(ValidatorOnSubmit) == "function" && ValidatorOnSubmit() == false) return false;
return true;
}
//]]>

<script type="text/javascript">
//<![CDATA[
var theForm = document.forms['form1'];
if (!theForm) {
    theForm = document.form1;
}
function __doPostBack(eventTarget, eventArgument) {
    if (!theForm.onsubmit || (theForm.onsubmit() != false)) {
        theForm.__EVENTTARGET.value = eventTarget;
        theForm.__EVENTARGUMENT.value = eventArgument;
        theForm.submit();
    }
}
//]]>
</script>
function WebForm_DoPostBackWithOptions(options) {
    var validationResult = true;
    if (options.validation) {
        if (typeof(Page_ClientValidate) == 'function') {
            validationResult = Page_ClientValidate(options.validationGroup);
        }
    }
    if (validationResult) {
        if ((typeof(options.actionUrl) != "undefined") && (options.actionUrl != null) && (options.actionUrl.length > 0)) {
            theForm.action = options.actionUrl;
        }
        if (options.trackFocus) {
            var lastFocus = theForm.elements["__LASTFOCUS"];
            if ((typeof(lastFocus) != "undefined") && (lastFocus != null)) {
                if (typeof(document.activeElement) == "undefined") {
                    lastFocus.value = options.eventTarget;
                }
                else {
                    var active = document.activeElement;
                    if ((typeof(active) != "undefined") && (active != null)) {
                        if ((typeof(active.id) != "undefined") && (active.id != null) && (active.id.length > 0)) {
                            lastFocus.value = active.id;
                        }
                        else if (typeof(active.name) != "undefined") {
                            lastFocus.value = active.name;
                        }
                    }
                }
            }
        }
    }
    if (options.clientSubmit) {
        __doPostBack(options.eventTarget, options.eventArgument);
    }
}

Answer 1

I don't think this is possible with the mechanize module: it doesn't have the ability to interact with JavaScript: its purely Python and HTTP based.

That said, you may be intested in python-spidermonkey module, which it seems is aimed at letting you do just this kind of thing. According to it's website it's aim is to let you

"Execute arbitrary JavaScript code from Python. Allows you to reference arbitrary Python objects and functions in the JavaScript VM"

I've not used it yet but it certainly looks like it would do what you are looking for, although it is still in alpha.

Answer 2

You may set cookies using cookielib

import mechanize
import cookielib
# add headers to your browser also
browser = mechanize.Browser()
browser.addheaders = [('User-agent', 'Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.1) Gecko/2008071615 Fedora/3.0.1-1.fc9 Firefox/3.0.1')]
cj = cookielib.LWPCookieJar()
browser.set_cookiejar(cj)

I doubt this is even relevant now, but oh well :)