Last Updated: March 08, 2017

Extract Data from XPath via Google Apps Script

You can get/extract data from a URL via Google Apps Script, Just pass the XPath and URL to monitor.

I have setup a Script that continuously monitors YCombinator's Top post, When it changes I get a Mail with the link.

function getDataFromXpath(path, url) {
 var data = UrlFetchApp.fetch(url);
 var text = data.getContentText();
 var xmlDoc = Xml.parse(text, true);

 // Replacing tbody tag because app script doesnt understand.
 path = path.replace("/html/","").replace("/tbody","","g");
 var tags = path.split("/");
 Logger.log("tags : " + tags);
 // getting the DOM of HTML
 var element = xmlDoc.getElement();

 for(var i in tags) {
 var tag = tags[i];
 Logger.log("Tag : " + tag);
 var index = tag.indexOf("[");
 if(index != -1) {
 var val = parseInt(tag[index+1]);
 tag = tag.substring(0,index);
 element = element.getElements(tag)[val-1];
 } else {
 element = element.getElement(tag);
 }
 //Logger.log(element.toXmlString());
 }
 return element.getText() + ' [ ' + element.getAttribute("href").getValue() + ' ] ';
}


function checkUpdateAndSendEmail() {
 var cache = CacheService.getPrivateCache();

 var url = "https://news.ycombinator.com/news";
 var path = "/html/body/center/table/tbody/tr[3]/td/table/tbody/tr/td[3]/a";
 var cached = cache.get(url);
 var text = getDataFromXpath(path, url);
 if(cached == null || cached != text) {
 cache.put(url, cached, 3666);
 MailApp.sendEmail("<email>", "YCombinator Top", text);
 Logger.log("Mail Sent!!! ");
 }
 Logger.log("text : " + text);
 Logger.log("cached : " + cached);
}

https://gist.github.com/vs4vijay/6724868

#google

#email

#appsscript