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Adding Header To A SOAP Call (Java equavalent in C#)

The SOAP API I am intending to use has given a working example in Java. In every request to the API one should add three values to the header (I just guess they are a domain, a password and api key). To this aim we override the org.apache.axis.client.Stub like this:
public class SeveraApiStubBase extends org.apache.axis.client.Stub {
#Override
public org.apache.axis.client.Call _createCall() throws ServiceException {
org.apache.axis.client.Call _call = super._createCall();
_call.addHeader(new org.apache.axis.message.SOAPHeaderElement(
"http://something.somethingelse.com/", "WebServicePassword", "API_KEY"));
return _call;
}
}
And then we run the method with the provided header.
I was wondering what the equivalent is in C#.
Update: The use of the IClientMessageInspector class
public object BeforeSendRequest(ref Message request, IClientChannel channel)
{
HttpRequestMessageProperty httpRequestMessage;
object httpRequestMessageObject;
if (request.Properties.TryGetValue(HttpRequestMessageProperty.Name, out httpRequestMessageObject))
{
httpRequestMessage = httpRequestMessageObject as HttpRequestMessageProperty;
if (string.IsNullOrEmpty(httpRequestMessage.Headers[USER_AGENT_HTTP_HEADER]))
{
httpRequestMessage.Headers[USER_AGENT_HTTP_HEADER] = this.m_userAgent;
}
}
else
{
httpRequestMessage = new HttpRequestMessageProperty();
httpRequestMessage.Headers.Add(USER_AGENT_HTTP_HEADER, this.m_userAgent);
request.Properties.Add(HttpRequestMessageProperty.Name, httpRequestMessage);
}
return null;
}

Normally you would use WCF if using C# rather than Axis. It is a little different of an approach than Axis.
Assuming you're making a client consuming an existing WSDL, you would start by using svcutil to generate your service contract code. Here is a link that describes this part. The example they give is a service with primitive inputs to all operations, so it doesn't show generation of complex type classes.
You can then use message inspectors to intercept the outgoing request and add a header. The IClientMessageInspector interface has the method BeforeSendRequest that passes a Message class as an argument. The Message class has a Headers collection where you can add whatever headers you need.

how to return a response body when header is missing in spring REST api

I am passing a header to a spring REST api like:
#RequestHeader(value="test-header")
header is mandatory here for the API, so I do not want to keep it optional.
when no header is passed, any call to the API returns a standard 400 error indicating that request is syntantically wrong and then it does not enter the REST API. But, I want to construct a proper ResponseBody and return a json for this error. I am not sure about the best way to do this. I thought about using spring interceptor and check if this header was passed or not, but then I am not sure if I can create a responsebody from here. Atleast I could not figure out how to do so.
will interceptor approach work for this? If yes, how? If not, then what are the options? Can someone please help on this?
Update:
This is how the REST API is:
public void methodA(#RequestHeader(value="test-header") String header, #RequestBody User user, HttpServletRequest httpRequest, HttpServletResponse httpResponse) {
...
...
}
When the header is present, it will enter the REST API and continue with the logic. But, if the header is not present, it does not enter the API and simply returns a standard 400 error.
The interceptor that I wrote is like:
public class XXXInterceptor extends HandlerInterceptorAdapter {
#Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
...
...
...
return true;
}
}

STEP1: Use spring validator annotation like #valid to validate your request.
STEP 2: Write your custom validator class. which will be responsible to check the header and see if it has value or it has the expected value.
STEP 3: If the request is not correct validator throws your custom exception.
STEP 4: write your exception handler class. In the class define what response must me returned if the exception in STEP 3 is caught.
For more information on Exception Handling in Spring.
In our current projet we do use a java interceptor to authenticate the request but nothing beyound that.

Write a method with the annotation #ExceptionHandler and use ServletRequestBindingException.class as this exception is thrown in case of miss. You can return any type of object from this method.
For example
#ExceptionHandler(ServletRequestBindingException.class)
public ResponseEntity<ResponseObject> handleHeaderError(){
ResponseObject responseObject=new ResponseObject();
responseObject.setStatus(Constants.ResponseStatus.FAILURE.getStatus());
responseObject.setMessage(header_missing_message);
ResponseEntity<ResponseObject> responseEntity=new ResponseEntity<ResponseObject>(responseObject, HttpStatus.BAD_REQUEST);
return responseEntity;
}

Another approach would be using Spring Interceptors (HandlerInterceptorAdapter), as you mentioned in your question, with #ControllerAdvice and return your JSON in an #ExceptionHandler method.
Take a look at the following post: http://www.journaldev.com/2651/spring-mvc-exception-handling-exceptionhandler-controlleradvice-handlerexceptionresolver-json-response-example

This is coming late but then, a very straightforward way to deal with this type of issue is to use a Controller Advice class which allows you to handle exceptions across the whole application in one global handling component.
The exception throw by spring is the MissingRequestHeaderException which you can then provide a custom handler in your controller advice class.
#Slf4j
#RestControllerAdvice
public class ControllerAdvice {
#ExceptionHandler(MissingRequestHeaderException.class)
#ResponseStatus(value = HttpStatus.BAD_REQUEST)
public ErrorResponse handleMissingRequestHeaderException(MissingRequestHeaderException ex) {
log.error(ex.getMessage(), ex);
return new ErrorResponse("Missing request header: " + ex.getHeaderName());
}
}
public class ErrorResponse implements Serializable {
private String message;
public ErrorResponse(String message) {
this.message = message;
}
}

Error message in REST webservices

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();
}
}

override http status with cxf

I'm using CXF for web services.
Because of some client restrictions, I need all web faults to return code 200 instead of 500.
I tried to use interceptors, depends on the phase I was able to either override the status and then the response is empty or the response is full with the fault but then the status is not overridden.
Any ideas how to do that?
Using interceptors, what would be the right phase?
I registered the interceptor like this:
#org.apache.cxf.interceptor.OutFaultInterceptors(interceptors = { "com.my.prod.core.service.itercept.HttpStatusInterceptor" })
and this is the interceptor:
public class HttpStatusInterceptor extends AbstractSoapInterceptor {
public HttpStatusInterceptor(){
super(Phase.POST_STREAM_ENDING);
}
#Override public void handleMessage(org.apache.cxf.binding.soap.SoapMessage msg) throws org.apache.cxf.interceptor.Fault{
msg.put(SoapMessage.RESPONSE_CODE, "200");
}}

Can you try
msg.put(SoapMessage.RESPONSE_CODE, 200);
so it ends up as and Integer object instead of a String. I think it's expecting the integer.

Changing content type in jax-rs REST service

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.