$http responseType: 'json' triggers DOM Exception 12 in Mobile Webkit

[quantizor]

Hi folks,

I'm building a nice little drag & drop upload form for a contest and came across an interesting error.

In trying to perform a simple $http.get call with some config passed, I've been getting DOM Exception 12 "SYNTAX ERROR" only in mobile phones with webkit-based browsers. Chrome does not seem to be affected.

Here's the actual code to reproduce (found in v1.2.6):

$http.get('/api/contest/submit.action', { params: $s.fields, responseType: 'json' }).then(function( response ){
    $s.submitted = true;
});

Has anyone else run into this? The DOM error points to the line in $http's source where it sets the xhr.responseType property.

[caitp]

responseType is from XMLHttpRequest2, which probably isn't supported on mobile safari 7 or something.

That said, I don't see anything in the IDL which would cause it to throw for setting the response type, it should probably just be ignored.

Any any rate, I can't seem to reproduce this on mobile Safari 7. Could you post a reproduction and list the affected devices+browsers you've tested with?

edit I can reproduce this with mobile safari 6.1 in ios simulator

[quantizor]

I saw this on an iPhone 4S running iOS 6.1.3. I had a coworker come by with an iPhone 5 and iOS 7 and report the same issue. I ended up just removing the responseType declaration, as Angular seems to do JSON conversion by default, but just wanted to raise the issue in case it was a red flag for a deeper problem.

[caitp]

It seems that the exception gets thrown when assigning xhr.responseType (although I see no reason in the IDL why that should happen!)

We could get around this by wrapping it in a try/catch block (but I don't really like this idea)

[caitp]

It looks like safari 6.1 doesn't support the "json" responseType. http://trac.webkit.org/changeset/154992 was checked in only a couple months ago, and I guess the 6.1 release didn't include that patch. So this explains it.

For what it's worth though, if you just use responseType="text" or ignore the responseType setting entirely, angular will automatically parse JSON for you. (which apparently you've already mentioned!)

[caitp]

I think this is probably a WON'TFIX as I don't think it's a totally great idea to hide the exception if it happens, so I'm gonna close this.

[caitp]

re-opening this for now as Igor suggests it might be worth working around the bug.

[quantizor]

It was definitely difficult to trace, so at least a note in the
documentation seems like a good idea.
On Feb 4, 2014 6:01 PM, "Caitlin Potter" notifications@github.com wrote:

re-opening this for now as Igor suggests it might be worth working around
the bug.

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