Spring Boot REST service exception handling

New answer (2016-04-20)

Using Spring Boot 1.3.1.RELEASE

New Step 1 - It is easy and less intrusive to add the following properties to the application.properties:

spring.mvc.throw-exception-if-no-handler-found=true
spring.resources.add-mappings=false

Much easier than modifying the existing DispatcherServlet instance (as below)! - JO'

If working with a full RESTful Application, it is very important to disable the automatic mapping of static resources since if you are using Spring Boot's default configuration for handling static resources then the resource handler will be handling the request (it's ordered last and mapped to /** which means that it picks up any requests that haven't been handled by any other handler in the application) so the dispatcher servlet doesn't get a chance to throw an exception.

New Answer (2015-12-04)

Using Spring Boot 1.2.7.RELEASE

New Step 1 - I found a much less intrusive way of setting the "throExceptionIfNoHandlerFound" flag. Replace the DispatcherServlet replacement code below (Step 1) with this in your application initialization class:

@ComponentScan()
@EnableAutoConfiguration
public class MyApplication extends SpringBootServletInitializer {
    private static Logger LOG = LoggerFactory.getLogger(MyApplication.class);
    public static void main(String[] args) {
        ApplicationContext ctx = SpringApplication.run(MyApplication.class, args);
        DispatcherServlet dispatcherServlet = (DispatcherServlet)ctx.getBean("dispatcherServlet");
        dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
    }

In this case, we're setting the flag on the existing DispatcherServlet, which preserves any auto-configuration by the Spring Boot framework.

One more thing I've found - the @EnableWebMvc annotation is deadly to Spring Boot. Yes, that annotation enables things like being able to catch all the controller exceptions as described below, but it also kills a LOT of the helpful auto-configuration that Spring Boot would normally provide. Use that annotation with extreme caution when you use Spring Boot.

Original Answer:

After a lot more research and following up on the solutions posted here (thanks for the help!) and no small amount of runtime tracing into the Spring code, I finally found a configuration that will handle all Exceptions (not Errors, but read on) including 404s.

Step 1 - tell SpringBoot to stop using MVC for "handler not found" situations. We want Spring to throw an exception instead of returning to the client a view redirect to "/error". To do this, you need to have an entry in one of your configuration classes:

// NEW CODE ABOVE REPLACES THIS! (2015-12-04)
@Configuration
public class MyAppConfig {
    @Bean  // Magic entry 
    public DispatcherServlet dispatcherServlet() {
        DispatcherServlet ds = new DispatcherServlet();
        ds.setThrowExceptionIfNoHandlerFound(true);
        return ds;
    }
}

The downside of this is that it replaces the default dispatcher servlet. This hasn't been a problem for us yet, with no side effects or execution problems showing up. If you're going to do anything else with the dispatcher servlet for other reasons, this is the place to do them.

Step 2 - Now that spring boot will throw an exception when no handler is found, that exception can be handled with any others in a unified exception handler:

@EnableWebMvc
@ControllerAdvice
public class ServiceExceptionHandler extends ResponseEntityExceptionHandler {

    @ExceptionHandler(Throwable.class)
    @ResponseBody
    ResponseEntity<Object> handleControllerException(HttpServletRequest req, Throwable ex) {
        ErrorResponse errorResponse = new ErrorResponse(ex);
        if(ex instanceof ServiceException) {
            errorResponse.setDetails(((ServiceException)ex).getDetails());
        }
        if(ex instanceof ServiceHttpException) {
            return new ResponseEntity<Object>(errorResponse,((ServiceHttpException)ex).getStatus());
        } else {
            return new ResponseEntity<Object>(errorResponse,HttpStatus.INTERNAL_SERVER_ERROR);
        }
    }

    @Override
    protected ResponseEntity<Object> handleNoHandlerFoundException(NoHandlerFoundException ex, HttpHeaders headers, HttpStatus status, WebRequest request) {
        Map<String,String> responseBody = new HashMap<>();
        responseBody.put("path",request.getContextPath());
        responseBody.put("message","The URL you have reached is not in service at this time (404).");
        return new ResponseEntity<Object>(responseBody,HttpStatus.NOT_FOUND);
    }
    ...
}

Keep in mind that I think the "@EnableWebMvc" annotation is significant here. It seems that none of this works without it. And that's it - your Spring boot app will now catch all exceptions, including 404s, in the above handler class and you may do with them as you please.

One last point - there doesn't seem to be a way to get this to catch thrown Errors. I have a wacky idea of using aspects to catch errors and turn them into Exceptions that the above code can then deal with, but I have not yet had time to actually try implementing that. Hope this helps someone.

Any comments/corrections/enhancements will be appreciated.

---

With Spring Boot 1.4+ new cool classes for easier exception handling were added that helps in removing the boilerplate code.

A new @RestControllerAdvice is provided for exception handling, it is combination of @ControllerAdvice and @ResponseBody. You can remove the @ResponseBody on the @ExceptionHandler method when use this new annotation.

i.e.

@RestControllerAdvice
public class GlobalControllerExceptionHandler {

    @ExceptionHandler(value = { Exception.class })
    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
    public ApiErrorResponse unknownException(Exception ex, WebRequest req) {
        return new ApiErrorResponse(...);
    }
}

For handling 404 errors adding @EnableWebMvc annotation and the following to application.properties was enough:
spring.mvc.throw-exception-if-no-handler-found=true

You can find and play with the sources here:
https://github.com/magiccrafter/spring-boot-exception-handling

---

I think ResponseEntityExceptionHandler meets your requirements. A sample piece of code for HTTP 400:

@ControllerAdvice
public class MyExceptionHandler extends ResponseEntityExceptionHandler {

  @ResponseStatus(value = HttpStatus.BAD_REQUEST)
  @ExceptionHandler({HttpMessageNotReadableException.class, MethodArgumentNotValidException.class,
      HttpRequestMethodNotSupportedException.class})
  public ResponseEntity<Object> badRequest(HttpServletRequest req, Exception exception) {
    // ...
  }
}

You can check this post

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Although this is an older question, I would like to share my thoughts on this. I hope, that it will be helpful to some of you.

I am currently building a REST API which makes use of Spring Boot 1.5.2.RELEASE with Spring Framework 4.3.7.RELEASE. I use the Java Config approach (as opposed to XML configuration). Also, my project uses a global exception handling mechanism using the @RestControllerAdvice annotation (see later below).

My project has the same requirements as yours: I want my REST API to return a HTTP 404 Not Found with an accompanying JSON payload in the HTTP response to the API client when it tries to send a request to an URL which does not exist. In my case, the JSON payload looks like this (which clearly differs from the Spring Boot default, btw.):

{
    "code": 1000,
    "message": "No handler found for your request.",
    "timestamp": "2017-11-20T02:40:57.628Z"
}

I finally made it work. Here are the main tasks you need to do in brief:

Make sure that the NoHandlerFoundException is thrown if API clients call URLS for which no handler method exists (see Step 1 below).

Create a custom error class (in my case ApiError) which contains all the data that should be returned to the API client (see step 2).

Create an exception handler which reacts on the NoHandlerFoundException and returns a proper error message to the API client (see step 3).

Write a test for it and make sure, it works (see step 4).

Ok, now on to the details:

Step 1: Configure application.properties

I had to add the following two configuration settings to the project's application.properties file:

spring.mvc.throw-exception-if-no-handler-found=true
spring.resources.add-mappings=false

This makes sure, the NoHandlerFoundException is thrown in cases where a client tries to access an URL for which no controller method exists which would be able to handle the request.

Step 2: Create a Class for API Errors

I made a class similar to the one suggested in this article on Eugen Paraschiv's blog. This class represents an API error. This information is sent to the client in the HTTP response body in case of an error.

public class ApiError {

    private int code;
    private String message;
    private Instant timestamp;

    public ApiError(int code, String message) {
        this.code = code;
        this.message = message;
        this.timestamp = Instant.now();
    }

    public ApiError(int code, String message, Instant timestamp) {
        this.code = code;
        this.message = message;
        this.timestamp = timestamp;
    }

    // Getters and setters here...
}

Step 3: Create / Configure a Global Exception Handler

I use the following class to handle exceptions (for simplicity, I have removed import statements, logging code and some other, non-relevant pieces of code):

@RestControllerAdvice
public class GlobalExceptionHandler {

    @ExceptionHandler(NoHandlerFoundException.class)
    @ResponseStatus(HttpStatus.NOT_FOUND)
    public ApiError noHandlerFoundException(
            NoHandlerFoundException ex) {

        int code = 1000;
        String message = "No handler found for your request.";
        return new ApiError(code, message);
    }

    // More exception handlers here ...
}

Step 4: Write a test

I want to make sure, the API always returns the correct error messages to the calling client, even in the case of failure. Thus, I wrote a test like this:

@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = SprintBootTest.WebEnvironment.RANDOM_PORT)
@AutoConfigureMockMvc
@ActiveProfiles("dev")
public class GlobalExceptionHandlerIntegrationTest {

    public static final String ISO8601_DATE_REGEX =
        "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z$";

    @Autowired
    private MockMvc mockMvc;

    @Test
    @WithMockUser(roles = "DEVICE_SCAN_HOSTS")
    public void invalidUrl_returnsHttp404() throws Exception {
        RequestBuilder requestBuilder = getGetRequestBuilder("/does-not-exist");
        mockMvc.perform(requestBuilder)
            .andExpect(status().isNotFound())
            .andExpect(jsonPath("$.code", is(1000)))
            .andExpect(jsonPath("$.message", is("No handler found for your request.")))
            .andExpect(jsonPath("$.timestamp", RegexMatcher.matchesRegex(ISO8601_DATE_REGEX)));
    }

    private RequestBuilder getGetRequestBuilder(String url) {
        return MockMvcRequestBuilders
            .get(url)
            .accept(MediaType.APPLICATION_JSON);
    }

The @ActiveProfiles("dev") annotation can be left away. I use it only as I work with different profiles. The RegexMatcher is a custom Hamcrest matcher I use to better handle timestamp fields. Here's the code (I found it here):

public class RegexMatcher extends TypeSafeMatcher<String> {

    private final String regex;

    public RegexMatcher(final String regex) {
        this.regex = regex;
    }

    @Override
    public void describeTo(final Description description) {
        description.appendText("matches regular expression=`" + regex + "`");
    }

    @Override
    public boolean matchesSafely(final String string) {
        return string.matches(regex);
    }

    // Matcher method you can call on this matcher class
    public static RegexMatcher matchesRegex(final String string) {
        return new RegexMatcher(regex);
    }
}

Some further notes from my side:

In many other posts on StackOverflow, people suggested setting the @EnableWebMvc annotation. This was not necessary in my case.

This approach works well with MockMvc (see test above).

---

What about this code ? I use a fallback request mapping to catch 404 errors.

@Controller
@ControllerAdvice
public class ExceptionHandlerController {

    @ExceptionHandler(Exception.class)
    public ModelAndView exceptionHandler(HttpServletRequest request, HttpServletResponse response, Exception ex) {
        //If exception has a ResponseStatus annotation then use its response code
        ResponseStatus responseStatusAnnotation = AnnotationUtils.findAnnotation(ex.getClass(), ResponseStatus.class);

        return buildModelAndViewErrorPage(request, response, ex, responseStatusAnnotation != null ? responseStatusAnnotation.value() : HttpStatus.INTERNAL_SERVER_ERROR);
    }

    @RequestMapping("*")
    public ModelAndView fallbackHandler(HttpServletRequest request, HttpServletResponse response) throws Exception {
        return buildModelAndViewErrorPage(request, response, null, HttpStatus.NOT_FOUND);
    }

    private ModelAndView buildModelAndViewErrorPage(HttpServletRequest request, HttpServletResponse response, Exception ex, HttpStatus httpStatus) {
        response.setStatus(httpStatus.value());

        ModelAndView mav = new ModelAndView("error.html");
        if (ex != null) {
            mav.addObject("title", ex);
        }
        mav.addObject("content", request.getRequestURL());
        return mav;
    }

}

---

@RestControllerAdvice is a new feature of Spring Framework 4.3 to handle Exception with RestfulApi by a cross-cutting concern solution:

 package com.khan.vaquar.exception;

import javax.servlet.http.HttpServletRequest;

import org.owasp.esapi.errors.IntrusionException;
import org.owasp.esapi.errors.ValidationException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.servlet.NoHandlerFoundException;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.khan.vaquar.domain.ErrorResponse;

/**
 * Handles exceptions raised through requests to spring controllers.
 **/
@RestControllerAdvice
public class RestExceptionHandler {

    private static final String TOKEN_ID = "tokenId";

    private static final Logger log = LoggerFactory.getLogger(RestExceptionHandler.class);

    /**
     * Handles InstructionExceptions from the rest controller.
     * 
     * @param e IntrusionException
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(value = IntrusionException.class)
    public ErrorResponse handleIntrusionException(HttpServletRequest request, IntrusionException e) {       
        log.warn(e.getLogMessage(), e);
        return this.handleValidationException(request, new ValidationException(e.getUserMessage(), e.getLogMessage()));
    }

    /**
     * Handles ValidationExceptions from the rest controller.
     * 
     * @param e ValidationException
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(value = ValidationException.class)
    public ErrorResponse handleValidationException(HttpServletRequest request, ValidationException e) {     
        String tokenId = request.getParameter(TOKEN_ID);
        log.info(e.getMessage(), e);

        if (e.getUserMessage().contains("Token ID")) {
            tokenId = "<OMITTED>";
        }

        return new ErrorResponse(   tokenId,
                                    HttpStatus.BAD_REQUEST.value(), 
                                    e.getClass().getSimpleName(),
                                    e.getUserMessage());
    }

    /**
     * Handles JsonProcessingExceptions from the rest controller.
     * 
     * @param e JsonProcessingException
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(value = JsonProcessingException.class)
    public ErrorResponse handleJsonProcessingException(HttpServletRequest request, JsonProcessingException e) {     
        String tokenId = request.getParameter(TOKEN_ID);
        log.info(e.getMessage(), e);
        return new ErrorResponse(   tokenId,
                                    HttpStatus.BAD_REQUEST.value(), 
                                    e.getClass().getSimpleName(),
                                    e.getOriginalMessage());
    }

    /**
     * Handles IllegalArgumentExceptions from the rest controller.
     * 
     * @param e IllegalArgumentException
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(value = IllegalArgumentException.class)
    public ErrorResponse handleIllegalArgumentException(HttpServletRequest request, IllegalArgumentException e) {
        String tokenId = request.getParameter(TOKEN_ID);
        log.info(e.getMessage(), e);
        return new ErrorResponse(   tokenId,
                                    HttpStatus.BAD_REQUEST.value(), 
                                    e.getClass().getSimpleName(), 
                                    e.getMessage());
    }

    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(value = UnsupportedOperationException.class)
    public ErrorResponse handleUnsupportedOperationException(HttpServletRequest request, UnsupportedOperationException e) {
        String tokenId = request.getParameter(TOKEN_ID);
        log.info(e.getMessage(), e);
        return new ErrorResponse(   tokenId,
                                    HttpStatus.BAD_REQUEST.value(), 
                                    e.getClass().getSimpleName(), 
                                    e.getMessage());
    }

    /**
     * Handles MissingServletRequestParameterExceptions from the rest controller.
     * 
     * @param e MissingServletRequestParameterException
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ExceptionHandler(value = MissingServletRequestParameterException.class)
    public ErrorResponse handleMissingServletRequestParameterException( HttpServletRequest request, 
                                                                        MissingServletRequestParameterException e) {
        String tokenId = request.getParameter(TOKEN_ID);
        log.info(e.getMessage(), e);
        return new ErrorResponse(   tokenId,
                                    HttpStatus.BAD_REQUEST.value(), 
                                    e.getClass().getSimpleName(), 
                                    e.getMessage());
    }

    /**
     * Handles NoHandlerFoundExceptions from the rest controller.
     * 
     * @param e NoHandlerFoundException
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.NOT_FOUND)
    @ExceptionHandler(value = NoHandlerFoundException.class)
    public ErrorResponse handleNoHandlerFoundException(HttpServletRequest request, NoHandlerFoundException e) {
        String tokenId = request.getParameter(TOKEN_ID);
        log.info(e.getMessage(), e);
        return new ErrorResponse(   tokenId,
                                    HttpStatus.NOT_FOUND.value(), 
                                    e.getClass().getSimpleName(), 
                                    "The resource " + e.getRequestURL() + " is unavailable");
    }

    /**
     * Handles all remaining exceptions from the rest controller.
     * 
     * This acts as a catch-all for any exceptions not handled by previous exception handlers.
     * 
     * @param e Exception
     * @return error response POJO
     */
    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
    @ExceptionHandler(value = Exception.class)
    public ErrorResponse handleException(HttpServletRequest request, Exception e) {
        String tokenId = request.getParameter(TOKEN_ID);
        log.error(e.getMessage(), e);
        return new ErrorResponse(   tokenId,
                                    HttpStatus.INTERNAL_SERVER_ERROR.value(), 
                                    e.getClass().getSimpleName(), 
                                    "An internal error occurred");
    }   

}

---

By default Spring Boot gives json with error details.

curl -v localhost:8080/greet | json_pp
[...]
< HTTP/1.1 400 Bad Request
[...]
{
   "timestamp" : 1413313361387,
   "exception" : "org.springframework.web.bind.MissingServletRequestParameterException",
   "status" : 400,
   "error" : "Bad Request",
   "path" : "/greet",
   "message" : "Required String parameter 'name' is not present"
}

It also works for all kind of request mapping errors. Check this article http://www.jayway.com/2014/10/19/spring-boot-error-responses/

If you want to create log it to NoSQL. You can create @ControllerAdvice where you would log it and then re-throw the exception. There is example in documentation https://spring.io/blog/2013/11/01/exception-handling-in-spring-mvc

---

For REST controllers, I would recommend to use Zalando Problem Spring Web.

https://github.com/zalando/problem-spring-web

If Spring Boot aims to embed some auto-configuration, this library does more for exception handling. You just need to add the dependency:

<dependency>
    <groupId>org.zalando</groupId>
    <artifactId>problem-spring-web</artifactId>
    <version>LATEST</version>
</dependency>

And then define one or more advice traits for your exceptions (or use those provided by default)

public interface NotAcceptableAdviceTrait extends AdviceTrait {

    @ExceptionHandler
    default ResponseEntity<Problem> handleMediaTypeNotAcceptable(
            final HttpMediaTypeNotAcceptableException exception,
            final NativeWebRequest request) {
        return Responses.create(Status.NOT_ACCEPTABLE, exception, request);
    }

}

Then you can defined the controller advice for exception handling as:

@ControllerAdvice
class ExceptionHandling implements MethodNotAllowedAdviceTrait, NotAcceptableAdviceTrait {

}

---

For people that want to response according to http status code, you can use the ErrorController way:

@Controller
public class CustomErrorController extends BasicErrorController {

    public CustomErrorController(ServerProperties serverProperties) {
        super(new DefaultErrorAttributes(), serverProperties.getError());
    }

    @Override
    public ResponseEntity error(HttpServletRequest request) {
        HttpStatus status = getStatus(request);
        if (status.equals(HttpStatus.INTERNAL_SERVER_ERROR)){
            return ResponseEntity.status(status).body(ResponseBean.SERVER_ERROR);
        }else if (status.equals(HttpStatus.BAD_REQUEST)){
            return ResponseEntity.status(status).body(ResponseBean.BAD_REQUEST);
        }
        return super.error(request);
    }
}

The ResponseBean here is my custom pojo for response.

---

Solution with dispatcherServlet.setThrowExceptionIfNoHandlerFound(true); and @EnableWebMvc @ControllerAdvice worked for me with Spring Boot 1.3.1, while was not working on 1.2.7

---

Simple exception controller class with RestController Annotation will take care the exception handling at controller level.

    @RestControllerAdvice
    public class ExceptionController
    {
        // Mention the exception here..
        @ExceptionHandler(value = MethodArgumentNotValidException.class)
        public ResponseEntity<?> exceptionHandler(MethodArgumentNotValidException e)
        {
            var errors = e.getBindingResult().getAllErrors().stream()
                          .map(DefaultMessageSourceResolvable::getDefaultMessage).collect(Collectors.toList());
            var response = new ResponseBuilder()
                .withHttpStatus(HttpStatus.BAD_REQUEST.value())
                .withMessage(CustomStatus.FAILED.getMessage())
                .withErrorCode(CustomStatus.FAILED.getValue())
                .withErrorDescription(errors)
                .build();
            return new ResponseEntity<>(response, HttpStatus.BAD_REQUEST);
        }
    }

---