CODEWITHSUNDEEP
javascriptjqueryajaxjson
Tom Doodler
Tom Doodler

Reputation: 1559

jQuery Ajax returns "parsererror" despite JSON is valid and return code is 201

I'm sending a query to a server and awaiting a JSON object in return:

var a = $.ajax(
{
    type: "POST",
    data: post_data,
    timeout: 5000,
    url: url,
    beforeSend: function (xhr)
    {
        xhr.setRequestHeader("Content-Type", "application/json"); 
    }
})
.success (function (data, status, jqxhr)
{       
    onSuccess();
})
.error (function(x, status, jqxhr) 
{   
    onError_(x);
});

That works perfectly, I'm getting the expected JSON in return:

{"readyState":4,"responseText":"","status":201,"statusText":"Created"}

But not onSuccess() but onError_() gets called and status is set to 'parsererror' despite the return is a valid JSON (I've tested it with various tools like this) and even the status of the JSON element is 201 which according to this page represents a positive status code:

10.2.2 201 Created

The request has been fulfilled and resulted in a new resource being created [...]

Is it possible, that jQuery's Ajax interprets the 201 status as a failure?

Update:

Also adding dataType: "json", to my request doesnt change the situation. The jQuery documentation for .ajax() says

dataType (default: Intelligent Guess (xml, json, script, or html))

So when I implemented it I thought jQuery wouldn't be so dumb to cause errors because it doesn't recognize JSON and it seems that I was right because the error remains the same.

Update:

The common fix for this problem seems to be, adding dataType: "json" to the ajax call, however this didn't work for me, so I did an ugly but working workaround:

.error (function(x, status, jqxhr) 
{
    if (x.status == 201) /* jQuery thinks, Status 201 means error, but it doesnt so we have to work around it here */
    {
        // handle success
        return;
    }

    // handle errors
}

Anyway, I'd be still interested in a proper fix

Upvotes: 1

Views: 4848

Answers (2)

pinturic
pinturic

Reputation: 2263

Be careful: ResponseText is equal to "" and that is not a valid json. It should be null or "{}"

Upvotes: 4

Harsh Aggarwal
Harsh Aggarwal

Reputation: 192

Also, write dataType: "json" in ajax call.

Upvotes: 0

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