Preventing DOM operations on null nodes (#166)

* Adding reset styles to prevent stray styles

* Preventing DOM operations on null nodes

* Accidental commit

src/index.js

@@ -47,6 +47,11 @@ function postRender(initPromise) {
     var expandButton = document.querySelector('#js-glimpse-expand-button');
     var collapseButton = document.querySelector('#js-glimpse-collapse-button');
 
+    if (!hudData) {
+        // element does not exist yet
+        return;
+    }
+
     ajaxView.postRender(initPromise);
     logsView.postRender(initPromise);
 

src/views/ajax.js

@@ -99,6 +99,11 @@ function update(request) {
 }
 function updateCounter(details, count) {
     var counter = document.getElementById(details.countId);
+    if (!counter) {
+        // element does not exist yet
+        return;
+    }
+
     counter.innerText = count;
     dom.addClass(counter, 'glimpse-section-value--update');
     if (details.timeout) {

src/views/data.js

@@ -60,6 +60,11 @@ function update(model) {
 function updateValue(target, summary) {
     const element = document.getElementById(target);
 
+    if (!element) {
+        // element does not exist yet
+        return;
+    }
+
     let content = summary.total;
     if (summary.total > 0) {
         dom.addClass(element, 'glimpse-time-ms');
@@ -96,6 +101,11 @@ function updateCoreListing(target, data, supportedRecords, isStatusCode) {
     }
 
     const targetElement = document.getElementById(target);
+    if (!targetElement) {
+        // element does not exist yet
+        return;
+    }
+
     if (content.length > 0) {
         targetElement.innerHTML = `${content}<div></div>`;
     }