Merge pull request umami-software#3381 from YektaDev/script-simplification

Script Simplification

Author: mikecao

src/tracker/index.js

@@ -8,19 +8,19 @@
     top,
     doNotTrack,
   } = window;
-  const { hostname, href, origin } = location;
   const { currentScript, referrer } = document;
-  const localStorage = href.startsWith('data:') ? undefined : window.localStorage;
-
   if (!currentScript) return;
 
+  const { hostname, href, origin } = location;
+  const localStorage = href.startsWith('data:') ? undefined : window.localStorage;
+
   const _data = 'data-';
   const _false = 'false';
   const _true = 'true';
   const attr = currentScript.getAttribute.bind(currentScript);
   const website = attr(_data + 'website-id');
   const hostUrl = attr(_data + 'host-url');
-  const tag = attr(_data + 'tag');
+  const tag = attr(_data + 'tag') || undefined;
   const autoTrack = attr(_data + 'auto-track') !== _false;
   const dnt = attr(_data + 'do-not-track') === _true;
   const excludeSearch = attr(_data + 'exclude-search') === _true;
@@ -41,11 +41,11 @@
     website,
     screen,
     language,
-    title,
+    title: document.title,
     hostname,
     url: currentUrl,
     referrer: currentRef,
-    tag: tag ? tag : undefined,
+    tag,
     id: identity ? identity : undefined,
   });
 
@@ -56,20 +56,14 @@
 
   /* Event handlers */
 
-  const handlePush = (state, title, url) => {
+  const handlePush = (_state, _title, url) => {
     if (!url) return;
 
     currentRef = currentUrl;
     currentUrl = new URL(url, location.href);
 
-    if (excludeSearch) {
-      currentUrl.search = '';
-    }
-
-    if (excludeHash) {
-      currentUrl.hash = '';
-    }
-
+    if (excludeSearch) currentUrl.search = '';
+    if (excludeHash) currentUrl.hash = '';
     currentUrl = currentUrl.toString();
 
     if (currentUrl !== currentRef) {
@@ -80,10 +74,8 @@
   const handlePathChanges = () => {
     const hook = (_this, method, callback) => {
       const orig = _this[method];
-
       return (...args) => {
         callback.apply(null, args);
-
         return orig.apply(_this, args);
       };
     };
@@ -92,96 +84,47 @@
     history.replaceState = hook(history, 'replaceState', handlePush);
   };
 
-  const handleTitleChanges = () => {
-    const observer = new MutationObserver(([entry]) => {
-      title = entry && entry.target ? entry.target.text : undefined;
-    });
-
-    const node = document.querySelector('head > title');
-
-    if (node) {
-      observer.observe(node, {
-        subtree: true,
-        characterData: true,
-        childList: true,
-      });
-    }
-  };
-
   const handleClicks = () => {
-    document.addEventListener(
-      'click',
-      async e => {
-        const isSpecialTag = tagName => ['BUTTON', 'A'].includes(tagName);
-
-        const trackElement = async el => {
-          const attr = el.getAttribute.bind(el);
-          const eventName = attr(eventNameAttribute);
-
-          if (eventName) {
-            const eventData = {};
-
-            el.getAttributeNames().forEach(name => {
-              const match = name.match(eventRegex);
-
-              if (match) {
-                eventData[match[1]] = attr(name);
-              }
-            });
-
-            return track(eventName, eventData);
-          }
-        };
-
-        const findParentTag = (rootElem, maxSearchDepth) => {
-          let currentElement = rootElem;
-          for (let i = 0; i < maxSearchDepth; i++) {
-            if (isSpecialTag(currentElement.tagName)) {
-              return currentElement;
-            }
-            currentElement = currentElement.parentElement;
-            if (!currentElement) {
-              return null;
-            }
-          }
-        };
+    const trackElement = async el => {
+      const eventName = el.getAttribute(eventNameAttribute);
+      if (eventName) {
+        const eventData = {};
 
-        const el = e.target;
-        const parentElement = isSpecialTag(el.tagName) ? el : findParentTag(el, 10);
+        el.getAttributeNames().forEach(name => {
+          const match = name.match(eventRegex);
+          if (match) eventData[match[1]] = el.getAttribute(name);
+        });
 
-        if (parentElement) {
-          const { href, target } = parentElement;
-          const eventName = parentElement.getAttribute(eventNameAttribute);
+        return track(eventName, eventData);
+      }
+    };
+    const onClick = async e => {
+      const el = e.target;
+      const parentElement = el.closest('a,button');
+      if (!parentElement) return trackElement(el);
 
-          if (eventName) {
-            if (parentElement.tagName === 'A') {
-              const external =
-                target === '_blank' ||
-                e.ctrlKey ||
-                e.shiftKey ||
-                e.metaKey ||
-                (e.button && e.button === 1);
+      const { href, target } = parentElement;
+      if (!parentElement.getAttribute(eventNameAttribute)) return;
 
-              if (eventName && href) {
-                if (!external) {
-                  e.preventDefault();
-                }
-                return trackElement(parentElement).then(() => {
-                  if (!external) {
-                    (target === '_top' ? top.location : location).href = href;
-                  }
-                });
-              }
-            } else if (parentElement.tagName === 'BUTTON') {
-              return trackElement(parentElement);
-            }
+      if (parentElement.tagName === 'BUTTON') {
+        return trackElement(parentElement);
+      }
+      if (parentElement.tagName === 'A' && href) {
+        const external =
+          target === '_blank' ||
+          e.ctrlKey ||
+          e.shiftKey ||
+          e.metaKey ||
+          (e.button && e.button === 1);
+        if (!external) e.preventDefault();
+        return trackElement(parentElement).then(() => {
+          if (!external) {
+            (target === '_top' ? top.location : location).href = href;
           }
-        } else {
-          return trackElement(el);
-        }
-      },
-      true,
-    );
+        });
+      }
+    };
+    document.addEventListener('click', onClick, true);
   };
 
   /* Tracking functions */
@@ -195,56 +138,40 @@
 
   const send = async (payload, type = 'event') => {
     if (trackingDisabled()) return;
-
-    const headers = {
-      'Content-Type': 'application/json',
-    };
-
-    if (typeof cache !== 'undefined') {
-      headers['x-umami-cache'] = cache;
-    }
-
     try {
       const res = await fetch(endpoint, {
         method: 'POST',
         body: JSON.stringify({ type, payload }),
-        headers,
+        headers: {
+          'Content-Type': 'application/json',
+          ...(typeof cache !== 'undefined' && { 'x-umami-cache': cache }),
+        },
         credentials: 'omit',
       });
 
       const data = await res.json();
-
       if (data) {
         disabled = !!data.disabled;
         cache = data.cache;
       }
     } catch (e) {
-      /* empty */
+      /* no-op */
     }
   };
 
   const init = () => {
     if (!initialized) {
+      initialized = true;
       track();
       handlePathChanges();
-      handleTitleChanges();
       handleClicks();
-      initialized = true;
     }
   };
 
-  const track = (name, data) => {
-    if (typeof name === 'string') {
-      return send({
-        ...getPayload(),
-        name,
-        data,
-      });
-    } else if (typeof name === 'object') {
-      return send({ ...name });
-    } else if (typeof name === 'function') {
-      return send(name(getPayload()));
-    }
+  const track = (obj, data) => {
+    if (typeof obj === 'string') return send({ ...getPayload(), name: obj, data });
+    if (typeof obj === 'object') return send(obj);
+    if (typeof obj === 'function') return send(obj(getPayload()));
     return send(getPayload());
   };
 
@@ -274,10 +201,9 @@
 
   let currentUrl = href;
   let currentRef = referrer.startsWith(origin) ? '' : referrer;
-  let title = document.title;
-  let cache;
-  let initialized;
+  let initialized = false;
   let disabled = false;
+  let cache;
   let identity;
 
   if (autoTrack && !trackingDisabled()) {