Calling wcf rest service from jquery doesn't work - wcf

Question

I have written a really simple wcf rest service which seems to work fine when I make requests to it through fiddler but I cannot get it to work when calling it from JQuery.
Service:
[ServiceContract]
public interface IService1
{
[OperationContract]
[WebInvoke(Method = "POST",
UriTemplate = "customers/{regionId}",
ResponseFormat = WebMessageFormat.Json
)]
Customer[] GetCustomers(String regionId);
}
[DataContract]
public class Customer
{
[DataMember]
public Guid Id { get; private set; }
[DataMember]
public String Name { get; private set; }
public Customer(Guid id, String name)
{
Id = id;
Name = name;
}
}
public class Service1 : IService1
{
public Customer[] GetCustomers(String regionId)
{
return new[]
{
new Customer(Guid.NewGuid(), "john"),
new Customer(Guid.NewGuid(), "pete"),
new Customer(Guid.NewGuid(), "ralph")
};
}
}
I can make requests to this service via fiddler and it returns the expected json. However, when I try and call it with JQuery ajax via the firebug console it always fails. Here is the call:
$.ajax({
type: "POST",
data: "{}",
url: "http://127.0.0.1:8081/json/customers/1",
contentType: "application/json; charset=utf-8",
dataType: "json",
success:function(res)
{
alert('success');
},
error: function(xhr)
{
alert('failed: '+xhr.responseText);
}
});
I always get the failed alert and the responseText is always blank. Any ideas would be greatly appreciated.

Answer 1

When you say "via Fiddler" do you mean "using Fiddler's request builder" or do you mean "with Fiddler running?"
Question: What URL is your website running on? You cannot generally make XHR requests to different servers (or ports, in FF) using XHR.