regex - Parsing malformed JSON in JavaScript

Question

Thanks for looking!

BACKGROUND

I am writing some front-end code that consumes a JSON service which is returning malformed JSON. Specifically, the keys are not surrounded with quotes:

{foo: "bar"}

I have NO CONTROL over the service, so I am correcting this like so:

var scrubbedJson = dirtyJson.replace(/(['"])?([a-zA-Z0-9_]+)(['"])?:/g, '"$2": ');

This gives me well formed JSON:

{"foo": "bar"}

Problem

However, when I call JSON.parse(scrubbedJson), I still get an error. I suspect it may be because the entire JSON string is surrounded in double quotes but I am not sure.

UPDATE

This has been solved--the above code works fine. I had a rogue single quote in the body of the JSON that was returned. I got that out of there and everything now parses. Thanks. Any help would be appreciated.

Answer 1

You can avoid using a regexp altogether and still output a JavaScript object from a malformed JSON string (keys without quotes, single quotes, etc), using this simple trick:

var jsonify = (function(div){
  return function(json){
    div.setAttribute('onclick', 'this.__json__ = ' + json);
    div.click();
    return div.__json__;
  }
})(document.createElement('div'));

// Let's say you had a string like '{ one: 1 }' (malformed, a key without quotes)
// jsonify('{ one: 1 }') will output a good ol' JS object ;)

Here's a demo: http://codepen.io/csuwldcat/pen/dfzsu (open your console)