Oh hello there, fellow SO members,
I have a web service that returns XML data using a simple get request that goes like this :
http://my-service:8082/qc/getData?paramX=0169¶mY=2
the service returns raw xml in the page according to the parameters' values.
I am trying to retrieve this data from a GET request in GWT using RequestBuilder, Request, etc.
However, the response gives me empty text, a Status code of ZERO (which doesn't mean anything and isn't supposed to happen), and so on.
Here's the simplified code that doesn't work.
public class SimpleXML implements EntryPoint {
public void onModuleLoad() {
this.doGet("http://my-service:8082/qc/getData", "0169", "2");
}
public void doGet(String serviceURL, String paramX, String paramY) {
final String getUrl = serviceURL + "?paramX=" + paramX + "&idTarification=" + paramY;
RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, getUrl);
try {
Request response = builder.sendRequest(null, new RequestCallback() {
#Override
public void onResponseReceived(Request request, Response response) {
response.getStatusCode(); // Gives me 0 (zero) :(
}
#Override
public void onError(Request request, Throwable exception) {
// ... doesn't matter for this example
}
});
} catch (RequestException e) {
// ... doesn't matter for this example
}
}
}
I don't get why this wouldn't work, since this is REALLY simple, I've seen tutorials and they all show me this way of doing things..
Thanks in advance
The reason is, that browsers do not allow cross-site requests with AJAX (see Same Origin Policy).
This means, that you can only call a service on the same server, same port (using the same protocol) as your HTML page. If you want to perform cross-site requests, you can use JSONP, as explained in http://code.google.com/webtoolkit/doc/latest/tutorial/Xsite.html.
Related
I'm working on a POC i need to use zuul as a sever to route 2 routes first will run normally but it has a custom post filter which will send another request to other api using some data of the response of the first requet,
so need to extract the response body of the first request into my custom post filter and get some specific attributes but i can not find the response as it always be null but the status code is 200.
how can i wait and get a value of specific attribute from the response and get the actual status code not just 200 as default value.
i tried to make this implementation using cloud gateway but i reached the same point of disability of extracting the response.
also i tried to make a response decorator but it failed too.
#Component
public class AddResponseHeaderFilter extends ZuulFilter {
#Override
public String filterType() {
return "post";
}
#Override
public int filterOrder() {
return 1;
}
#Override
public boolean shouldFilter() {
return true;
}
#Override
public Object run() {
System.out.println("this is my filter");
RequestContext context = RequestContext.getCurrentContext();
HttpServletRequest request = new HttpServletRequestWrapper(context.getRequest());
System.out.println(String.format("%s request to %s", request.getMethod(), request.getRequestURL().toString()));
HttpServletResponse servletResponse = context.getResponse();
// return an address only
System.out.println(context.getResponseBody().toString());
servletResponse.addHeader("X-Foo", UUID.randomUUID().toString());
return null;
}
}
RequestContext.getCurrentContext().getResponseDataStream() works fine for me, I am also able to manipulate the response.
import java.nio.charset.Charset;
import org.springframework.util.StreamUtils;
RequestContext ctx = RequestContext.getCurrentContext();
HttpServletRequest request = ctx.getRequest();
String requestLog = StreamUtils.copyToString(request.getInputStream(),
Charset.forName("UTF-8"));
I am currently working with the Restlets framework, and I cannot find a way to manually set the HTTP response code within a service method. Consider the following snippet of code:
public class MyResource extends ServerResource {
#Post("json")
public Representation doSomething(Representation entity) throws IOException {
int status = 200;
try {
// do something which might throw an exception
}
catch (Exception e) {
// log the exception
// *** I would like to assign HTTP status 500 here ***
status = 500;
}
JSONObject responseJSON = new JSONObject();
responseJSON.put("result", "some data");
Representation rep = new JsonRepresentation(responseJSON.toJSONString());
return rep;
}
}
I have the ability to catch and log an exception, should one occur, but it is not clear how I can change the HTTP response code. As far as I know, returning from doSomething will automatically be handled by Restlets with an 200 HTTP response code.
I know how to assign the status code directly from a filter or servlet, but is it possible to do this within Restlets, without going down the servlet layer?
As far as I know, there is an object called ResponseEntity which you can use to operate with microservices and a request-response programming model, which allows you to specify the returning HTTP return code. However, you need entities for this, and I think this goes below your abstraction level of Servlets.
You can change them to some predefined values such as HTTP.INTERNAL_SERVER_ERROR and such, which translate to a value in the end, which you can Google in the end.
I hope this was of some help
EDIT:
Import the necessary resource for a ResponseEntity object. In STS, it is
import org.springframework.http.ReponseEntity;
import org.springframework.http.HttpStatus;
public class MyResource extends ServerResource {
#Post("json")
public ResponseEntity<Representation> doSomething(Representation entity) throws IOException {
int status = 200;
try {
// do something which might throw an exception
}
catch (Exception e) {
ResponseEntity<Representation> response = null;
response = new ResponseEntity<Representation>(HttpStatus.INTERNAL_SERVER_ERROR);
return response;
}
JSONObject responseJSON = new JSONObject();
responseJSON.put("result", "some data");
Representation rep = new JsonRepresentation(responseJSON.toJSONString());
return rep;
}
And sorry for the delay. I am new to Stack Overflow
I am calling REST webservices from JSP using AJAX . Can you tell me the best way to send custom error message from REST webservice to JSP ?
Consider using HTTP response codes with (possibly) json response bodies to supply any required information so the client application can react accordingly.
Consider using the WebapplicationException. You can give it the Errorcode (also custom ones) and a body for the response. You could use the JSON Format if you have a complex structure to display your errors but i would suggest just using the an errormessage (for example in case of a bad request, what part of the request was bad).
If you are using JAX-RS REST webservice, you can configure Spring #Controller. Your method should produce application/json and return Response object, like in this example:
#GET
#Path("/get/{id}")
#Produces(MediaType.APPLICATION_JSON)
public Response getUserById(#PathParam("id") String userId) {
// Here your logic
Foo foo = new Foo();
foo.setMsg("Bad Request");
foo.setData("User " + userId + " not found")
return Response.status(400).entity(foo).build();
}
And from AJAX, you can catch error message
// Get user details
$.getJSON(encodeURI("./rest/user/get/" + userId), function(data) {
// Some logic on success
// Fail
}).fail( function(jqxhr) {
console.log(jqxhr.responseJSON.msg);
});
There are a couple of ways.
1. You can look at the response status you receive from the web service. The statuses starting with 2** are a success response (Eg: 200, 201), the ones starting with 4** or 5** are errors.
But the optimal way to handle and track exceptions is to use ExceptionMapper. You can write your own class that implements ExceptionMapper like below:
#Provider
public class GenericExceptionMapper implements ExceptionMapper<Throwable> {
#Override
public Response toResponse(Throwable arg0) {
return Response.status(Status.INTERNAL_SERVER_ERROR)
.entity("Custom Exception: Error retrieving data")
.build();
}
}
You can write your own custom exceptions like below or can throw blanket exception like below. The above approach is the preferred one though.
#Provider
public class GenericExceptionMapper implements ExceptionMapper<Throwable> {
#Override
public Response toResponse(Throwable arg0) {
return Response.status(Status.INTERNAL_SERVER_ERROR)
.entity("Custom Exception: Error retrieving data")
.build();
}
}
A test case for my contact formular page is to make sure it's always in a secure context respectively using SSL. Basically, all I want to know, is that I have a given request where request.secure = true;
The following response does not contain any information about this and its headers are empty:
#Test
public void shouldShowContactForm() {
Response response = GET("/contact");
// How can I ask the response, if the complete URL is in HTTPS?
}
Even if I explicitly set my own request, I cant see the right way to do this:
#Test
public void shouldShowContactFormInSSLContext() {
Request request = newRequest();
request.secure = true;
Response response = GET(request, "/contact");
// Is it now possible?
}
Is this even the right approach to test this or am I simply missing something important about the request/response?
For this question I think what I've done for my apps in the past is have a #before interceptor on all my controllers that looks like this.
#Before
static void checkSSL(){
if(Play.mode.equals(Play.Mode.PROD)){
if(!request.secure) {
Router.ActionDefinition cashTicketDefinition = Router.reverse(request.controller + "." + request.actionMethod);
cashTicketDefinition.absolute();
String url = cashTicketDefinition.url.replaceFirst( "http:", "https:");
redirect(url, true);
}
}
}
Forgive me, but I may not be familiar with all the lingo necessary to ask this question properly.
I'm working on a fairly simple REST web service in Java using the org.apache.cxf.jaxrs.ext implementation of jax-rs. The method header is like this:
#GET
#Path("json/{fullAlias}")
#Produces({"application/json"})
public String json(#PathParam("fullAlias") String fullAlias, #Context MessageContext req)
where MessageContext is org.apache.cxf.jaxrs.ext.MessageContext.
There are two things I'm trying to accomplish that I can't seem to figure out:
Change the content-type if certain conditions are met (e.g. for an error)
Change the status code of the response
I've tried using changing the response by accessing it through the MessageContext:
HttpServletResponse response = req.getHttpServletResponse();
response.setContentType("text/plain")
response.setStatus("HttpServletResponse.SC_BAD_REQUEST);
But these changes have no bearing on the response sent; with or without the #Produces annotation, setting the content type inside the method doesn't affect the actual content type (With the annotation, it of course returns "application/json", without it defaults to "text/html").
I am returning a simple String as the body. I've entertained trying to return a javax.ws.rs.core.Response object to do what I want, but I don't know much about it.
How would I change the content type and/or the status codes from inside this method?
One approach is to throw a WebApplicationException, as described by Pace, which will work if you are looking to specifically handle an error condition. If you are looking to be able to change your content at any time for any reason, then you will want to take a look at returning a Response as the result of your service method rather than a String. Returning a Response gives you the greatest amount of control over how your service responds to the client request (it does require more code than returning a simple string).
Here is an example of how you would can make use of the Response object:
#GET
#Path("json/{fullAlias}")
public Response json(#PathParam("fullAlias") String fullAlias, #Context MessageContext req) {
...
if (success) {
ResponseBuilder rBuild = Response.ok(responseData, MediaType.APPLICATION_JSON);
return rBuild.build();
}
else {
ResponseBuilder rBuild = Response.status(Response.Status.BAD_REQUEST);
return rBuild.type(MediaType.TEXT_PLAIN)
.entity("error message")
.build();
}
}
I'm not sure if it's the best approach but I've done the following to solve your question #1.
public WebApplicationException createStatusException(String statusMessage) {
ResponseBuilder rb = Response.noContent();
rb = rb.type(MediaType.TEXT_PLAIN);
rb = rb.status(Status.BAD_REQUEST);
rb = rb.entity(statusMessage);
return new WebApplicationException(rb.build());
}
EDIT: I then threw the resulting WebApplicationException.
You can write your own Response Filter to change the content-type header.
#Provider
public class MimeAddingFilter implements ContainerResponseFilter {
#Override
public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext)
throws IOException {
responseContext.getHeaders().add("Content-Type", "image/png");
}
}
This filter will add the "image/png" content-type header. You can also change or remove headers in JAX-RS response filters.