Implement functionality for feature-detecting webStorage

js/utils/feature_detection_utils.js

@@ -24,3 +24,38 @@
  */
 export const dragAndDropAvailable = 'draggable' in document.createElement('div') &&
     !/Mobile|Android|Slick\/|Kindle|BlackBerry|Opera Mini|Opera Mobi/i.test(navigator.userAgent);
+
+/**
+ * Function that detects whether localStorage/sessionStorage is both supported
+ * and available.
+ * Taken from:
+ * https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API/Using_the_Web_Storage_API
+ *
+ * We're explicitly NOT exporting this function, as we want for both localStorage, as well as
+ * sessionStorage proxy functions to be exported.
+ *
+ * @param  {oneOfType(['localStorage', 'sessionStorage'])}
+ * @return {bool}      Is localStorage or sessionStorage available on this browser
+ */
+function storageAvailable(type) {
+    try {
+        var storage = window[type],
+            x = '__storage_test__';
+        storage.setItem(x, x);
+        storage.removeItem(x);
+        return true;
+    }
+    catch(e) {
+        return false;
+    }
+}
+
+/**
+ * Function detects whether sessionStorage is both supported
+ * and available.
+ * @return {bool} Is sessionStorage available on this browser
+ */
+export function sessionStorageAvailable() {
+    return storageAvailable('sessionStorage');
+}
+