function getIndexJsonPromise() {

			var sApiInfoRootURL = window['sap-ui-documentation-config'] && window['sap-ui-documentation-config'].apiInfoRootURL;

			if (oLibraryDataCache["index"]) {
				return Promise.resolve(oLibraryDataCache["index"]);
			}

			return new Promise(function (resolve, reject) {
				jQuery.ajax({
					async: true,
					url : sApiInfoRootURL || ResourcesUtil.getResourceOriginPath("/docs/api/api-index.json"),
					dataType : 'json',
					success : function(vResponse) {
						var aResult = vResponse.symbols || [];
						oLibraryDataCache["index"] = aResult;
						resolve(aResult);
					},
					error : function () {
						jQuery.ajax({
							async: true,
							url : ResourcesUtil.getResourceOriginPath("../../../../../../docs/api/api-index.json"),
							dataType : 'json',
							success : function(vResponse) {
								var aResult = vResponse.symbols || [];
								oLibraryDataCache["index"] = aResult;
								resolve(aResult);
							},
							error : function () {
								Log.error("failed to load api-index.json");
								oLibraryDataCache["index"] = [];
								resolve([]);
							}
						});
					}
				});
			});
		}
Root path to read api.json files from