test browser localStorage before using it

diff --git a/web/dashboard.js b/web/dashboard.js
index 346a8e9c10d0e3b5e42eb7364c6146c461a7d4df..02e171d4af7d3c330f722b655a98dcf6f2ef4660 100644 (file)
--- a/web/dashboard.js
+++ b/web/dashboard.js
@@ -363,6 +363,28 @@ var NETDATA = window.NETDATA || {};
         callback: {} // only used for resetting back to defaults
     };
 
+    NETDATA.localStorageTested = -1;
+    NETDATA.localStorageTest = function() {
+        if(NETDATA.localStorageTested !== -1)
+            return NETDATA.localStorageTested;
+
+        if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
+            var test = 'test';
+            try {
+                localStorage.setItem(test, test);
+                localStorage.removeItem(test);
+                NETDATA.localStorageTested = true;
+            }
+            catch (e) {
+                NETDATA.localStorageTested = false;
+            }
+        }
+        else
+            NETDATA.localStorageTested = false;
+
+        return NETDATA.localStorageTested;
+    };
+
     NETDATA.localStorageGet = function(key, def, callback) {
         var ret = def;
 
@@ -371,7 +393,7 @@ var NETDATA = window.NETDATA || {};
             NETDATA.localStorage.callback[key.toString()] = callback;
         }
 
-        if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
+        if(NETDATA.localStorageTest() === true) {
             try {
                 // console.log('localStorage: loading "' + key.toString() + '"');
                 ret = localStorage.getItem(key.toString());
@@ -413,7 +435,7 @@ var NETDATA = window.NETDATA || {};
             NETDATA.localStorage.callback[key.toString()] = callback;
         }
 
-        if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
+        if(NETDATA.localStorageTest() === true) {
             // console.log('localStorage: saving "' + key.toString() + '" with value "' + JSON.stringify(value) + '"');
             try {
                 localStorage.setItem(key.toString(), JSON.stringify(value));

diff --git a/web/index.html b/web/index.html
index 55a605aa786767155de45bc8051e2125b1d3c9dc..c9685ba3a0b6133ec2f3d893ca7b2548c9be0194 100644 (file)
--- a/web/index.html
+++ b/web/index.html
@@ -508,11 +508,33 @@
         // --------------------------------------------------------------------
         // check options that should be processed before loading netdata.js
 
+        var localStorageTested = -1;
+        function localStorageTest() {
+            if(localStorageTested !== -1)
+                return localStorageTested;
+
+            if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
+                var test = 'test';
+                try {
+                    localStorage.setItem(test, test);
+                    localStorage.removeItem(test);
+                    localStorageTested = true;
+                }
+                catch (e) {
+                    localStorageTested = false;
+                }
+            }
+            else
+                localStorageTested = false;
+
+            return localStorageTested;
+        }
+
         function loadLocalStorage(name) {
             var ret = null;
 
             try {
-                if(typeof Storage !== "undefined" && typeof localStorage === 'object')
+                if(localStorageTest() === true)
                     ret = localStorage.getItem(name);
             }
             catch(error) {
@@ -530,7 +552,7 @@
         function saveLocalStorage(name, value) {
             // console.log('saving: ' + name.toString() + ' = ' + value.toString());
             try {
-                if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
+                if(localStorageTest() === true) {
                     localStorage.setItem(name, value.toString());
                     return true;
                 }
@@ -3290,4 +3312,4 @@
     </div>
 </body>
 </html>
-<script type="text/javascript" src="dashboard.js?v20170127-1"></script>
+<script type="text/javascript" src="dashboard.js?v20170204-1"></script>