Data is null when Json contains NaN

When a response object has a NaN value in it, axios silently fails and gives a response object with data: null.

We understand that NaN, Infinity, and -Infinity aren’t allowed by json, but if that’s the case then the library should throw an error saying that the response can’t be processed. We just found this bug after a lot of very annoying and mysterious debugging, and it would have been nice to understand right away what the problem was.

Here is a screenshot of the request that failed (sensitive information has been redacted):

and here’s the shortened response text:

[
    {
        "id": 3,
        "date_created": "2018-03-12T17:49:16.260937",
        "date_updated": "2018-03-12T17:49:16.260937",
        "current_value": NaN
    }
]

It’s interesting to note that the chrome devtools understand and parse this response.

[Axnyff]

It looks like it’s the regular behavior of the browser: https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/responseType

var a = new XMLHttpRequest(); a.open(‘GET’, ‘/yolo.json?’); a.responseType = ‘json’; a.send()

axios does nothing, it’s the browser which just fails silently

[bhansenmd]

That’s a bummer. Thanks for your help anyways 😃