Merge branch 'winh-dropdown-ajax-cache' into 'master'

Use AjaxCache in Droplab Ajax plugin

Closes #31897

See merge request !11171

app/assets/javascripts/droplab/plugins/ajax.js

 /* eslint-disable */
 
+import AjaxCache from '~/lib/utils/ajax_cache';
+
 const Ajax = {
-  _loadUrlData: function _loadUrlData(url) {
-    var self = this;
-    return new Promise(function(resolve, reject) {
-      var xhr = new XMLHttpRequest;
-      xhr.open('GET', url, true);
-      xhr.onreadystatechange = function () {
-        if(xhr.readyState === XMLHttpRequest.DONE) {
-          if (xhr.status === 200) {
-            var data = JSON.parse(xhr.responseText);
-            self.cache[url] = data;
-            return resolve(data);
-          } else {
-            return reject([xhr.responseText, xhr.status]);
-          }
-        }
-      };
-      xhr.send();
-    });
-  },
   _loadData: function _loadData(data, config, self) {
     if (config.loadingTemplate) {
       var dataLoadingTemplate = self.hook.list.list.querySelector('[data-loading-template]');
@@ -31,7 +14,6 @@ const Ajax = {
   init: function init(hook) {
     var self = this;
     self.destroyed = false;
-    self.cache = self.cache || {};
     var config = hook.config.Ajax;
     this.hook = hook;
     if (!config || !config.endpoint || !config.method) {
@@ -48,14 +30,10 @@ const Ajax = {
       this.listTemplate = dynamicList.outerHTML;
       dynamicList.outerHTML = loadingTemplate.outerHTML;
     }
-    if (self.cache[config.endpoint]) {
-      self._loadData(self.cache[config.endpoint], config, self);
-    } else {
-      this._loadUrlData(config.endpoint)
-        .then(function(d) {
-          self._loadData(d, config, self);
-        }, config.onError).catch(config.onError);
-    }
+
+    AjaxCache.retrieve(config.endpoint)
+      .then((data) => self._loadData(data, config, self))
+      .catch(config.onError);
   },
   destroy: function() {
     this.destroyed = true;