SecurityError: Dom Exception 18 is thrown when local storage/cookies are blocked in Safari on iOS 7.1.2

[nbaronov]

Hello,

Please note an unhandled SecurityError exception is thrown, resulting in Angular crash, when storing something in local storage on Safari on iOS 7.1.2 with blocked cookies (Settings > Safari > Block Cookies > Always). I guess disabling cookies also disables local storage. With other two choices of block cookies setting ("From third parties and advertisers" and "Never") everything works fine.

The issue occurs on angular-translate-storage-local.js, line 25:

    var hasLocalStorageSupport = 'localStorage' in $window && $window.localStorage !== null;

and more specifically while accessing $window.localStorage to check if it is null.

I was able to fix this by moving access to $window.localStorage inside the try block (lines 28-30) like this:

    var hasLocalStorageSupport;
    try {
      hasLocalStorageSupport = 'localStorage' in $window && $window.localStorage !== null;
      var testKey = 'pascalprecht.translate.storageTest';
      $window.localStorage.setItem(testKey, 'foo');
      $window.localStorage.removeItem(testKey);
    } catch (e) {
      hasLocalStorageSupport = false;
    }

With above change the code never stores anything (since it can't), but at least Angular doesn't crash. I don't like silent failures like this one, but I'm not sure how to handle this within angular-translate. Maybe an event should be emitted ...

Please let me know what do you think.

Please note this is a repost of closed angular-translate/bower-angular-translate-storage-local#4, requested by @PascalPrecht.

[knalli]

When it is blocked so save, the storage handler can not save. That's fine. Therefor the patch seems to be okay.

[knalli]

Ehm.. this has already landed in master? 59aa2a0

Is this an issue any more?

[0x-r4bbit]

@nbaronov is it this here?
59aa2a0

[nbaronov]

@knalli, @PascalPrecht

Hey guys,

Yes, the issue is in 59aa2a0.

As I wrote in the top post, the exception is thrown when $window.localStorage is checked if it is not null on angular-translate-storage-local.js, line 25:

    var hasLocalStorageSupport = 'localStorage' in $window && $window.localStorage !== null;

So the fix I thought about is to move the access to $window.localStorage inside try block (lines 28-30), so the exception is caught.

[knalli]

You mean 'localeStorage' in $window is true, but $window.localStorage !== null throws an exception?

[nbaronov]

@knalli

Yes, $window.localStorage !== null throws SecurityError: Dom Exception 18.

I've found it out by decomposing the statement

var hasLocalStorageSupport = 'localStorage' in $window && $window.localStorage !== null;

into something like this:

var hasLocalStorageSupport;
if ('localStorage' in $window) {
  if ($window.localStorage !== null) {
     hasLocalStorageSupport == true
   }
}

and noticed the exception was thrown from this line:

  if ($window.localStorage !== null) {

[knalli]

@nbaronov Okay, I'm with you. Browsers' JS VMs have such neat api from time to time..

Do want make a PR? Be sure reading the contributions guidelines regarding the correct branches and so on..

[knalli]

Which also confirms 59aa2a0 did not solve the issue #384 correctly.

[nbaronov]

@knalli I'll check the guidelines and create a PR. It might also fix issue #384.

[knalli]

Fix landed as 75504cb

• 53a8bad the fix for the fix (browser do not throw an exception, but store anything different than null into it.

[JackieWYB]

After removing the block cookie settings from safari, works like a charm. thanks @nbaronov .