Add support for Global site tag (gtag.js) - Google Analytics

1 files changed, 51 insertions, 0 deletions

diff --git a/assets/js/ga.js b/assets/js/ga.js
new file mode 100644
index 0000000..2f855c3
--- /dev/null
+++ b/assets/js/ga.js
@@ -0,0 +1,51 @@
+function isDoNotTrackEnabled() {
+    if (typeof window === 'undefined') return false
+    const {doNotTrack, navigator} = window
+
+    // Do Not Track Settings across browsers
+    const dnt = (doNotTrack || navigator.doNotTrack || navigator.msDoNotTrack)
+
+    if (!dnt) return false
+
+    return dnt === true ||
+        dnt === 1 ||
+        dnt === 'yes' ||
+        (typeof dnt === 'string' && dnt.charAt(0) === '1');
+}
+
+if (isDoNotTrackEnabled()) {
+    // Skip analytics for users with Do Not Track enabled
+    console.info('[TRACKING]: Respecting DNT with respect to analytics...')
+} else {
+    // Known DNT values not set, so we will assume it's off.
+    const data = JSON.parse(document.getElementById('ed-data').innerHTML)
+
+    if (typeof data !== 'undefined' && data.analytics_code) {
+        (function () {
+            // New Google Site Tag (gtag.js) tagging/analytics framework
+            // See: https://developers.google.com/gtagjs
+            const base_url = 'https://www.googletagmanager.com'
+            let script = document.createElement("script");
+
+            script.src = base_url + "/gtag/js?id=" + data.analytics_code;
+            script.type = "text/javascript";
+            script.async = true;
+
+            document.getElementsByTagName("head")[0].appendChild(script);
+        }())
+
+        window.dataLayer = window.dataLayer || [];
+
+        function gtag() {
+            dataLayer.push(arguments);
+        }
+
+        gtag('js', new Date());
+
+        // Setup the project analytics code and send a pageview
+        gtag('config', data.analytics_code, {
+            'anonymize_ip': true,
+            'cookie_expires': 30 * 24 * 60 * 60  // 30 days
+        })
+    }
+}