Angular interceptor to reformat ISO 8601 strings into Javascript date objects

DateInterceptor.js

angular.module('dateInterceptor',[])
.config(['$httpProvider', function ($httpProvider) {

    var regexIso8601 = /^(\d{4}|\+\d{6})(?:-(\d{2})(?:-(\d{2})(?:T(\d{2}):(\d{2}):(\d{2})\.(\d{1,})(Z|([\-+])(\d{2}):(\d{2}))?)?)?)?$/;

    // function to parse through response json and replace ISO8601 date strings with date objects
    var convertDateStringsToDates = function(input) {
        // Ignore things that aren't objects.
        if (typeof input !== "object") return input;

        for (var key in input) {
            if (!input.hasOwnProperty(key)) continue;

            var value = input[key];
            var match;
            // Check for string properties which look like dates.
            if (typeof value === "string" && (match = value.match(regexIso8601))) {
                var milliseconds = Date.parse(match[0])
                if (!isNaN(milliseconds)) {
                    input[key] = new Date(milliseconds);
                }
            } else if (typeof value === "object") {
                // Recurse into object
                convertDateStringsToDates(value);
            }
        }
    };

    // push the transform into the transform array
    $httpProvider.defaults.transformResponse.push(function(responseData){
        convertDateStringsToDates(responseData);
        return responseData;
    });
}]);

Beware that this regex doesn't match all ISO8601 date strings. We've switched to using the regex from over here

^([\+-]?\d{4}(?!\d{2}\b))((-?)((0[1-9]|1[0-2])(\3([12]\d|0[1-9]|3[01]))?|W([0-4]\d|5[0-2])(-?[1-7])?|(00[1-9]|0[1-9]\d|[12]\d{2}|3([0-5]\d|6[1-6])))([T\s]((([01]\d|2[0-3])((:?)[0-5]\d)?|24\:?00)([\.,]\d+(?!:))?)?(\17[0-5]\d([\.,]\d+)?)?([zZ]|([\+-])([01]\d|2[0-3]):?([0-5]\d)?)?)?)?$ - See more at: http://www.pelagodesign.com/blog/2009/05/20/iso-8601-date-validation-that-doesnt-suck/#sthash.n4QweZIl.dpuf