Sunday, February 2, 2014

I'm trying to make an ajax call from jquery to a rest service. The rest service used is right from a tutorial of mkyong's blog, this one: http://www.mkyong.com/webservices/jax-rs/integrate-jackson-with-resteasy/
The service works, but when i try to make a call from jQuery, in Firebug there is a 200 status code, but in the response section, nothing.
Here is the html page with the ajax call:


    
I can't figure it out where I went wrong, could you please tell me what i am doing wrong?
Thanks!
share|improve this question
1 
Is your site running on http://localhost:8080 as well? If it's not (http://localhost/ is not the same), you'll have to make your API output JSONP. –  Rocket Hazmat Aug 18 '11 at 19:02 
 
no, it's just a simple html, it's running on double click :D –  DaJackal Aug 18 '11 at 19:05
 
I meant, what is the URL that points to this page? –  Rocket Hazmat Aug 18 '11 at 19:06 
1 
You are getting blocked by the same origin policy, you'll need to use JSONP. –  Rocket Hazmat Aug 18 '11 at 19:08
 
... or server your html from an HTTP server –  Jeremy Heiler Aug 18 '11 at 19:09
show 2 more comments

4 Answers

up vote35down voteaccepted
You are running your HTML from a different host than the host you are requesting. Because of this, you are getting blocked by the same origin policy.
One way around this is to use JSONP. This allows cross-site requests.
In JSON, you are returned:
{a: 5, b: 6}
In JSONP, the JSON is wrapped in a function call, so it becomes a script, and not an object.
callback({a: 5, b: 6})
You need to edit your REST service to accept a parameter called callback, and then to use the value of that parameter as the function name. You should also change the content-type toapplication/javascript.
For example: http://localhost:8080/restws/json/product/get?callback=process should output:
process({a: 5, b: 6})
In your JavaScript, you will need to tell jQuery to use JSONP. To do this, you need to append ?callback=? to the URL.
$.getJSON("http://localhost:8080/restws/json/product/get?callback=?",
   function(data) {
     alert(data);         
   });
If you use $.ajax, it will auto append the ?callback=? if you tell it to use jsonp.
$.ajax({ 
   type: "GET",
   dataType: "jsonp",
   url: "http://localhost:8080/restws/json/product/get",
   success: function(data){        
     alert(data);
   }
});
share|improve this answer
 
it's perfecty working now, and i think i understood. thanks –  DaJackal Aug 18 '11 at 19:19
 
You're welcome. JSONP is kind of a 'hack' to get data from other URLs, it's pretty cool. –  Rocket HazmatAug 18 '11 at 19:19
 
i get a response now in firebug, but it doesn't enter in function(data). do you know why? –  DaJackal Aug 18 '11 at 19:21
 
@DaJackal: Did you remember to have the webservice wrap the JSON in a function call? –  Rocket HazmatAug 18 '11 at 19:22
1 
I did it after all, after understanding how query param in rest service works, thank you very much! – DaJackal Aug 18 '11 at 20:48
show 11 more comments

No comments: