How to handle response with undefined body?

Question

I understand that my issue is that jQuery is trying to parse the body of the response as json, but the body is undefined, and thus throws an error.

I cannot change the response. This is the default response from Jenkins servers. It sends a 201, 404, or 500 in the header, which I would like to handle.

my ajax:

 $(document).ready(function () {
    $('#reviewForm').bootstrapValidator({
      ...stuff...
      ...validation...
  }) 

 .on('success.form.bv', function (e) {
// Prevent form submission
e.preventDefault();

// Get the form instance
var $form = $(e.target);

// Use Ajax to submit form data
$.ajax({
    type: 'POST',
    url: url+$form.serialize(),
    dataType: 'text',
    complete: function() {
        alert("Success.");
    },
    error: function(xhr, status, text) {
        alert("failure");
    }
});

Despite a successful post (201 created), it will still hit error because of the syntax error due to the undefined body.

I would gladly handle the errors in the error: part of ajax, but I cant for the life of me figure out how to get the status code out of the header of the response.

And like I said, I would change the response if I could, but its just how Jenkins works.

Thank you.

EDIT: response header

Status Code: 201 Created
Connection: Keep-Alive
Content-Type: text/plain; charset=UTF-8
Date: Wed, 01 Oct 2014 14:51:12 GMT
Keep-Alive: timeout=15, max=100
Location: https://jenkins....
Server: Jetty(8.y.z-SNAPSHOT)
Transfer-Encoding: chunked

and this is the xhr (xml http response)

{
"readyState": 0,
"status": 0,
"statusText": "error"
}

Answer 1

You can have specific callbacks for status codes such as:

$.ajax({
    ...
   statusCode: {
     201: function() { /* I received a 201 */ },
     404: function() { /* I received a 404 */ },
     500: function() { /* I received a 500 */ }
   }
});

This is listed in the documentation

Answer 2

The status code determines which of the functions (i.e. complete ,error, or success ) that jQuery will fire.

So, try this:

$.ajax({
    type: 'POST',
    url: url,
    dataType: 'text',
    complete: function(response) {
        console.log(response); 
    }); 

In the future, this will allow you to debug a bit better. (via your inspect element console)

But, the status code, in this example, will be in

response.status

The error function will fire on anything that isn't a 200 --- so you will be best off using only the complete function, and simply putting your error in the default block of a switch-case statement...

[...]
complete: function(response){
    switch(response.status){
        case 201: 
           alert("success"
        break;
        default:
            alert("Something unexpected occurred"); 
        break;
}

Answer 3

Just use the complete handler - it will run after success or error have been called. Either way, for both complete and error, the first parameter is a jqXHR object, which has a status property which will give you the status of the response.

$.ajax({
    type: 'POST',
    url: url,
    dataType: 'text',
    complete: function(xhr) {
        //this handler runs regardless of success or error
        //query xhr.status for the response code
    }
});

Answer 4

If I well mean this, u want check a respons from server (201, 200, 500): maybe use .awlways()

$.ajax({
   type: 'POST',
   url: url,
   dataType: 'text',
   always: function(status){
      alert(status);
   }
});

or u can use a getAllResponseHeaders() on xhr object ?

Answer 5

You can use statusCode

$.ajax({
   type: 'POST',
   url: url,
   statusCode: {
      200: function (response) {
         alert('200');
      },
      201: function (response) {
         alert('201');
      },
      404: function (response) {
         alert('400');
      }
   }, success: function () {
      alert('Success');
   },
});