How to differentiate Ajax requests from normal Http requests?

Question

I am using JSF framework in my application. I need to run a specific script before the render response phase in my Phase Listener class.

Condition for running this script is that, if the request triggered is a Ajax request i need to run the script, if the request triggered is a Http request i should not run that script.

Can anyone please help me to differentiate the requests recieved.?

Might be of interest: http://stackoverflow.com/questions/216173/differentiating-between-an-ajax-call-browser-request — UltraInstinct, Feb 03 '11 at 12:14

score 18 · Accepted Answer · answered Feb 03 '11 at 12:06

18

Ajax requests have usually a X-Requested-With: XMLHttpRequest request header. In JSF, you can obtain the request headers by ExternalContext#getRequestHeaderMap().

ExternalContext externalContext = facesContext.getExternalContext();
Map<String, String> headers = externalContext.getRequestHeaderMap();
boolean ajax = "XMLHttpRequest".equals(headers.get("X-Requested-With"));

answered Feb 03 '11 at 12:06

BalusC

1,082,665
372
3,610
3,555

if you are using RF then `request.getParameter("AJAXREQUEST")==null` will also work – jmj Feb 03 '11 at 12:10
Yes, you can also hook on implementation/library-specific parameters/attributes, but that tight-couples your code to specific implementations/libraries. – BalusC Feb 03 '11 at 12:11
1

Where do ajax requests originate? JSF? JS library? Homegrown? Anyway, just determine the request headers to see if there's a viable key/value pair which differs between normal and ajax requests. Do `System.out.println(headers);` to see them. – BalusC Feb 03 '11 at 14:16

score 4 · Answer 2 · answered Feb 03 '11 at 12:06

4

Ajax requests set a server variable X-Requested-With to XMLHttpRequest. You can use that information to differentiate between ajax and normal requests.

answered Feb 03 '11 at 12:06

Tatu Ulmanen

123,288
34
187
185

score 3 · Answer 3 · answered Feb 01 '13 at 15:14

3

private boolean isAjaxRequest() {
  PartialViewContext partialViewContext = FacesContext.getCurrentInstance().getPartialViewContext();
  return null != partialViewContext && partialViewContext.isAjaxRequest();
}

answered Feb 01 '13 at 15:14

eirirlar

814
6
24

How to differentiate Ajax requests from normal Http requests?

3 Answers3

Linked