Minimal Analytics Snippet

minimal-analytics-snippet.js

(function (history, trackingId, options) {
    const getParameterByName = (paramName) => {
        var searchString = window.location.search.substring(1),
            i, val, params = searchString.split("&");
        for (i=0;i<params.length;i++) {
          val = params[i].split("=");
          if (val[0] == paramName) {
            return val[1] || undefined;
          }
        }
        return undefined;
    };
    const generateId = () => {
        return '_' + Math.random().toString(36).substr(2, 9);
    };
    const getId = () => {
        if (!localStorage.cid) {
            localStorage.cid = generateId()
        }
        return localStorage.cid;
    };
    const serialize = (obj) => {
        var str = [];
        for (var p in obj) {
            if (obj.hasOwnProperty(p)) {
                if(obj[p] !== undefined) {
                    str.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));
                }
            }
        }
        return str.join("&");
    };
    const pageView = () => {
        setTimeout(() => {
            const data = {
                v: '1',
                aip: options.anonymizeIp ? 1 : undefined,
                tid: trackingId,
                cid: getId(),
                t: 'pageview',
                sd: options.colorDepth && screen.colorDepth ? `${screen.colorDepth}-bits` : undefined,
                dr: getParameterByName('ref'),
                dt: document.title,
                dl: document.location.origin + document.location.pathname + document.location.search,
                ul: options.language ? (navigator.language || "").toLowerCase() : undefined,
                de: options.characterSet ? document.characterSet : undefined,
                sr: options.screenSize ? `${(window.screen || {}).width}x${(window.screen || {}).height}` : undefined,
                vp: options.screenSize && window.visualViewport ? `${(window.visualViewport || {}).width}x${(window.visualViewport || {}).height}` : undefined
            };

            var xhr = new XMLHttpRequest();
            xhr.open("GET", `https://www.google-analytics.com/collect?${serialize(data)}&z=${Math.random()}`, true);
            xhr.send(null);
        }, 10);
    };
    const pushState = history.pushState;
    history.pushState = function (state) {
        if (typeof history.onpushstate == "function") {
            history.onpushstate({ state: state });
        }
        pageView()
        return pushState.apply(history, arguments);
    }
    pageView();
})(window.history, "XX-XXXXXXXXX-X", {
    anonymizeIp: true,
    colorDepth: true,
    characterSet: true,
    screenSize: true,
    language: true
});