diff --git a/web/src/app/js/base.js b/web/src/app/js/base.js
index e3f844c..c200fb1 100644
--- a/web/src/app/js/base.js
+++ b/web/src/app/js/base.js
@@ -177,6 +177,33 @@ function _get_func_params(func) {
 }
 
 const http = {
+	cache: {
+		_key: function(name) { return 'httpcache__'+name },
+		get: function(name) {
+			const key = http.cache._key(name);
+			try { return JSON.parse(localStorage[key]) }
+			catch (e) { }
+			return localStorage[key];
+		},
+		set: function(name, value) {
+			const key = http.cache._key(name);
+			localStorage[key] = value;
+			localStorage[key+'_ts'] = new Date().getTime();
+		},
+		del: function(name) { http.cache.expire(name) },
+		expire: function(name) {
+			const key = http.cache._key(name);
+			delete localStorage[key];
+			delete localStorage[key+'_ts'];
+		},
+		expired: function(name, secs) {
+			const key = http.cache._key(name);
+			const ts = new Date().getTime();
+			const ts2 = parseInt(localStorage[key+'_ts']);
+			if (isNaN(ts2)) return true;
+			return ((ts - ts2) / 1000) > secs;
+		},
+	},
 	request: function(method, path, payload, callbk) {
 		payload = payload || null;
 		callbk = callbk || null;