Get latest news by emails on google apps script trigger

rsstoemail.gs

// data feed URLs
var dataSources = [

  "http://blog.qt.io/feed/",
  
  "http://feed.rutracker.cc/atom/f/1426.atom",
  
  "http://feeds2.feedburner.com/blogspot/hsDu",

];
  
// Settings
var EMAIL_TITLE = "News digest";
var daystimer = 31; // Number of days out to scan events, set the same period in project's trigger (Day timer/ Week timer/ Month timer). You will recive only new messages.
var maxmsgsize = 300000; // Value in bytes, try to decrease it if the message does not pass. There is a limit on the body size per email. (Gmail clips emails that have a message size larger than 102kb, and hides the full content behind a View entire message link.)

var showDescription = true; // Print full feed item.

var deliverAddress = Session.getActiveUser().getEmail(); // "username@domain";
var url = ''; // Paste here OPML url


function SendEmail(Message) {

    Message += "<br/><a>Emails left for today: </a>" + MailApp.getRemainingDailyQuota();
    GmailApp.sendEmail(deliverAddress, EMAIL_TITLE, "", {
        htmlBody: Message
    });

}

/*******
 ** Trying to deliver all updates from parsed feeds into one or several emails (there is a limit on the body size per email). Run it to test the script.
 */
function deliverNews() {

    var FullEmail = "<h1>" + EMAIL_TITLE + "</h1>\n";
    var parsedFeedItems = "";
    var itemsize = 0;

    if (url !== '')
        opmlparser(url);

    var i = 0;
    do {
        FullEmail = "<h1>" + EMAIL_TITLE + "</h1>\n";
        while (i < dataSources.length) {
            parsedFeedItems = retrieveFeedItems(dataSources[i]);
            itemsize = roughSizeOfObject(parsedFeedItems); //???

            if (itemsize < maxmsgsize) {
                if ((roughSizeOfObject(FullEmail) + itemsize) < maxmsgsize) {
                    FullEmail += parsedFeedItems;
                    i++;
                } else
                    break;
            } else {
                FullEmail += "<p>This feed " + dataSources[i] + " is too large, try to decrease daystimer value or increase maxmsgsize value.</p>";
                i++;
                break;
            }
        }

        try {
            FullEmail += SendEmail(FullEmail);
        } catch (Exception) {
            FullEmail = Exception + "<br/>Try to decrease maxFullEmailsize value. There is a limit on the body size per email.";
            FullEmail += SendEmail(FullEmail);
            break;
        }

    } while (i < dataSources.length);

    Logger.log(FullEmail.length);
}

/*******
 ** Retrive and parse items from one feed to html
 */
function retrieveFeedItems(feedUrl) {

    var parsedItems = "<div>";
    try {
        var feedSrc = UrlFetchApp.fetch(feedUrl).getContentText();
        var feedDoc = XmlService.parse(feedSrc);
        if (feedDoc)
            var root = feedDoc.getRootElement();
    } catch (Exception) {
        parsedItems += "Can't fetch feed " + feedUrl + " " + Exception + "<br/>";
    }
  
    var type = "";
    if (root && root.getName() == "rss") {
        var version = root.getAttribute("version").getValue();
        if (version == "2.0")
            type = "rss2";
    } else if (root && root.getName() == "feed") {
        type = "atom";
    }


    var pubTime = "";
    var date = "";


    if (type == "atom") {
        var atom = XmlService.getNamespace('http://www.w3.org/2005/Atom');
        var entries = root.getChildren('entry', atom);

        for (var i = 0; i < entries.length; i++) {

            var pubTimeName = (entries[i].getChild('published', atom)) ? 'published' : 'updated';
            pubTime = entries[i].getChild(pubTimeName, atom).getValue();
            date = pubTime.split(/[: T-]/).map(parseFloat);
            date = new Date(date[0], date[1] - 1, date[2], date[3] || 0, date[4] || 0, date[5] || 0, 0);
          
            if (!limitheadlines(date)) {
                parsedItems += "<li>" +
                    root.getChild('title', atom).getText() + " " +
                    "<a href='" + entries[i].getChild("link", atom).getAttribute('href').getValue() + "'>" +
                    entries[i].getChildText("title", atom) + "</a> " + pubTime + "<br/>";
                if (showDescription) {
                    parsedItems += (entries[i].getChildText('summary', atom) ? entries[i].getChildText('summary', atom) : "");
                    parsedItems += (entries[i].getChildText('content', atom) ? entries[i].getChildText('content', atom) : "");
                }
                parsedItems += "</li><br/>";
            }
        }
    }

    if (type == "rss2") {
        var items = root.getChild("channel").getChildren("item");

        for (var i = 0; i < items.length; i++) {
          
            pubTime = items[i].getChildText("pubDate");
            date = new Date(pubTime);
          
            if (!limitheadlines(date)) {
                parsedItems += "<li>" +
                    root.getChild("channel").getChildText("title") + " " +
                    "<a href='" + items[i].getChildText("link") + "'>" + items[i].getChildText("title") +"</a> " +
                    pubTime + "\n<br/>";
                if (showDescription) {
                    parsedItems += (items[i].getChildText('description') ? items[i].getChildText('description') : "");
                    var contentNS = XmlService.getNamespace('http://purl.org/rss/1.0/modules/content/');
                    parsedItems += (items[i].getChildText('encoded', contentNS) ? items[i].getChildText('encoded', contentNS) : "");
                }
                parsedItems += "</li><br/>";
            }
        }
    }
  
    parsedItems += "</div>";
    return parsedItems;
}

/*******
 ** Scan only new messages.
 */
function limitheadlines(date) {

    var todaydate = new Date();
    var millisecondstimer = 86400000 * daystimer + 3600000; // 1 hour = 3600000ms
    var mfrom = todaydate.valueOf() - millisecondstimer;
    if (date.valueOf() <= mfrom)
        return true;
    else
        return false;
}

/*******
 ** Calculate size of javascript object, it is not a accurate value
 */
function roughSizeOfObject(object) {

    var objectList = [];
    var stack = [object];
    var bytes = 0;
    while (stack.length) {
        var value = stack.pop();

        if (typeof value === 'boolean') {
            bytes += 4;
        } else if (typeof value === 'string') {
            bytes += value.length * 2;
        } else if (typeof value === 'number') {
            bytes += 8;
        } else if (
            typeof value === 'object' && objectList.indexOf(value) === -1) {
            objectList.push(value);

            for (var i in value) {
                stack.push(value[i]);
            }
        }
    }
    return bytes;
}

function opmlparser(url) {

    var xml = UrlFetchApp.fetch(url).getContentText();
    var document = XmlService.parse(xml);

    var outlines = "";
    outlines = document.getRootElement().getChild('body').getChild('outline').getChildren('outline');
    if (outlines === "")
        outlines = document.getRootElement().getChild('body').getChildren('outline');

    for (var i = 0; i < outlines.length; i++)
        dataSources.push(outlines[i].getAttribute('xmlUrl').getValue());
}

/*******

> *Note*: Set number of days out to scan events in script variable called “daystimer”, and set the same period in trigger, under the Resources menu, select “Project Triggers”. (Day timer/ Week timer/ Month timer) Then run the deliverNews function to preview your news digest.

It’s not ideal for now, but it already saves time.

Google user-agents:
"Mozilla/5.0 (compatible; Google-Apps-Script)"
"Mozilla/5.0 (Windows NT 5.1; rv:11.0) Gecko Firefox/11.0 (via ggpht.com GoogleImageProxy)"

## APIs Used
 * [UrlFetchApp] (https://developers.google.com/apps-script/reference/url-fetch/url-fetch-app)
 * [XmlService] (https://developers.google.com/apps-script/reference/xml-service/xml-service)
 * [GmailApp] (https://developers.google.com/apps-script/reference/gmail/gmail-app)
*/