#ControllerAdvice does not catch MySQLIntegrityConstraintViolationException - spring-boot

I am making a Spring Boot app with MySQL database attached to it.
I have already marked username as unique in the user-table, and the DB throws a MySQLIntegrityConstraintViolationException when i try to add a new user with an existing username.
Is there a way to make the ControllerAdvice handle this exception ? I tried making the handler like this :
#ExceptionHandler(MySQLIntegrityConstraintViolationException.class)
#ResponseStatus(HttpStatus.CONFLICT)
#ResponseBody
public MyBadInputResponse databaseIntegrityViolationDuplicate(MySQLIntegrityConstraintViolationException ex) {
MyBadInputResponse bir = new MyBadInputResponse("The request value already exists in the database",
ex.getLocalizedMessage());
logger.error(bir.toString());
return bir;
}
But it doesn't work.

Related

Does spring boot automatically take care of error handling in the context of JpaRepository methods?

When using Spring Boot, I am unsure if error handling is already being taken care of by the Spring Framework, or if I have to implement it. For example, consider a controller method, which handles a DELETE request:
#DeleteMapping("/{studentId}")
public ResponseEntity<Long> deleteProfilePicture(#PathVariable Long studentId) {
return ResponseEntity.ok(profilePictureService.deleteprofilePictureByStudentId(studentId));
}
Is this fine, or should I instead wrap it inside a try-catch block:
#DeleteMapping("/{studentId}")
public ResponseEntity<Long> deleteProfilePicture(#PathVariable Long studentId) throws Exception {
try {
profilePictureService.deleteProfilePictureByStudentId(studentId));
} catch (DataAccessException e) {
throw new Exception("cannot delete profile picture of student: " + studentId);
}
}
Also: If I let my method deleteProfilePicture throw this Exception, who is handling the Exception? This must somehow be taken care of by Spring Boot, since it is possible to implement it without yielding any errors. Anyhow, what is the correct way of error handling in this scenario?
Spring Boot will turn the exception into an error response to the caller of the REST API. This does not mean that you shouldn't implement your own error handling logic, which you definitely should. As an example, you could use #ControllerAdvice to have a global exception handling for your application. Something along the following lines:
#ControllerAdvice
#Slf4j
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {
#ExceptionHandler(value = {Exception.class})
public ResponseEntity<Object> handleGenericExceptions(Exception exception, WebRequest webRequest) {
log.error("Handling: ", exception);
HttpStatus errorCode = HttpStatus.INTERNAL_SERVER_ERROR;
return this.handleExceptionInternal(exception, new ErrorInfo(errorCode.value(), "Unexpected Internal Server Error"), new HttpHeaders(), errorCode, webRequest);
}
}
You can read more about error handling in Spring Boot at https://www.baeldung.com/exception-handling-for-rest-with-spring.

Spring 5 exception handling - ResponseStatusException model

I was reading the article - https://www.baeldung.com/exception-handling-for-rest-with-spring
which says
Spring 5 introduced the ResponseStatusException class.
We can create an instance of it providing an HttpStatus and optionally
a reason and a cause:
I started implementing it , and the code is
custom exception
#ResponseStatus(code = HttpStatus.NOT_FOUND, reason = "Actor Not Found")
public class ActorNotFoundException extends Exception {
private static final long serialVersionUID = 1L;
public ActorNotFoundException(String errorMessage) {
super(errorMessage);
}
}
method in service
public String updateActor(int index, String actorName) throws ActorNotFoundException {
if (index >= actors.size()) {
throw new ActorNotFoundException("Actor Not Found in Repsoitory");
}
actors.set(index, actorName);
return actorName;
}
controller
#GetMapping("/actor/{id}")
public String getActorName(#PathVariable("id") int id) {
try {
return actorService.getActor(id);
} catch (ActorNotFoundException ex) {
throw new ResponseStatusException(HttpStatus.NOT_FOUND, "Actor Not Found", ex); //agreed it could be optional, but we may need original exception
}
}
repo:
https://github.com/eugenp/tutorials/tree/master/spring-5/src/main/java/com/baeldung/exception
Question:
why ResponseStatusException in controller again has to specify reason - "Actor Not Found" ?, as the service already said - ""Actor Not Found in Repsoitory"
What is the proper way to adapt to ResponseStatusException model?
It looks like a mistake. Ideally the service shouldn't use any HTTP code, so I would remove the annotation in ActorNotFoundException. Everything else seems fine, the exception is caught in the controller and ResponseStatusException is thrown which is good, because it's a proper layer to put HTTP stuff.
Overall it is better to use #ControllerAdvice instead of ResponseStatusException. it gives you a unified exception handling solution. Although it is not a good idea from a design point of view, ResponseStatusException can help you to avoid creating your custom exceptions and use it at the service level to throw in case of an Exception.
to avoid writing the message again you can use the message that is already available in thrown exception:
throw new ResponseStatusException(HttpStatus.NOT_FOUND, ex.getMessage() , ex);
for examples and more info you can refer to the following articles:
Spring Boot Exception Handling — #ControllerAdvice
Spring Boot Exception Handling — ResponseStatusException

How to send error message with restfulAPI using SpringBoot

I have server which is built using SpringBoot and restful api's. It is simple CRUD application.
I am trying to check if email already exists while adding a new user.
I am not sure how to send error messages over rest api. I have tried like this:
UserController.java
//POST method for adding one user
#PostMapping("/addUser")
public ResponseEntity<User> addUser(#RequestBody User user){
User existingUser = userRepository.findByEmail(user.getEmail());
if(existingUser != null){
throw new UserAlreadyExistException("User with this email already exists");
}
return new ResponseEntity<>(service.saveUser(user), HttpStatus.OK) ;
}
UserAlreadyExistException.java
public class UserAlreadyExistException extends RuntimeException{
public UserAlreadyExistException(String message) {
super(message);
}
}
When I test it with Postman I get Error: 500 Internal Server Error
And in InteliJ I have this exception thrown:
com.example.library.UserAlreadyExistException: User with this email
already exists
Is this a correct way to do it or what is the best practice?
What you're looking for is #ControllerAdvice and #ExceptionHandler. The way such exceptions are handled is:
Create a global exception handler and annotate with #ControllerAdvice
Catch your exception using #ExceptionHandler in one of the methods specific to a certain exception.
So, adding below code will catch the exception and return custom response.
#ControllerAdvice
public class GlobalExceptionHandler {
#ExceptionHandler
public ResponseEntity<Object> handleAuthenticationException(UserAlreadyExistException e) {
// do what you want with e
return new ResponseEntity<>("User already exists", HttpStatus.OK);
}

Spring Boot Security OAuth - handle InternalAuthenticationServiceException

My Spring Boot OAuth REST application returns "401 Unauthorized" status when the database connection failure(Spring Security throws InternalAuthenticationServiceException ).
It's strange, and I need to change status to "500 Internal server error" that client can provide some adequate description, like "service is not available".
If I use WebResponseExceptionTranslator then I can catch response, but if I change HTTP status, it works only when the database active. If the database is shutdown, then I get "401 Unauthorized" again.
How can I solve this problem most gracefully?
Depends on which level the exception is thrown, you might want to add exception handler to your login controller:
#ExceptionHandler(InternalAuthenticationServiceException.class)
public ModelAndView handleError(HttpServletRequest req, Exception ex) {
// convert exception to 500, add logging and
}
Learn more about exception handling here:
https://spring.io/blog/2013/11/01/exception-handling-in-spring-mvc
I fix this by adding "try catch" around jdbcTemplate request in my custom UserDetailService.
protected List<UserDetails> loadUsersByUsername(String username) {
try {
userDetailsList = this.getJdbcTemplate().query( USERS_BY_USERNAME, new String[]{username},
new RowMapper() {
public UserDetails mapRow( ResultSet rs, int rowNum ) throws SQLException {
String username = rs.getString( 1 );
/* etc. map user fields */
return new SecurityUser( username, /* other params... */ );
}
});
} catch (CannotGetJdbcConnectionException e){
logger.error( "UserDetailService SQL error: " + e.getMessage(), e );
}
return userDetailsList;
}
And then I check InternalAuthenticationServiceException
by WebResponseExceptionTranslator and change response status.
It seems that when I catch CannotGetJdbcConnectionException then something ruins in chain. It works, but I will leave my question open, maybe someone can offer a more clear solution.

Spring Oauth with multiple users tables

I am creating an application using Spring with Oauth2 as a backend for two apps (provider app and a consumer app). I have two different types of users; Providers, and consumers, each with its own db table.
The problem I am facing is that I cannot find a way to know if the request is coming from a provider or a customer, as each one will be in a different db table.
The username is Not unique between the two tables. So, a provider and a consumer can have the same username (and password).
I think any of the following solutions will suffice, however, I can’t find any way to implement any of them.
Having two different endpoints for each user class. e.g. “/provider/oauth/token” and “/consumer/oauth/token”. Each with its custom authentication manager.
Or: Having two authorization servers in the same Spring application, and then mapping their “/oauth/token” to different endpoints.
Or: Sending custom data in the oauth request to know where the request is coming from, and then dynamically selecting an authentication manager.
Or: Associating different authentication manager to different OAuth clients, and then ensuring that each app will have its respective client ID.
If any of these solutions is possible, or if there is another way to accomplish this, please let me know.
Any help is appreciated.
Edit - Solution
Following the answer below, I added another client with a different client ID, check the id in the UserDetailsService and then decide which db to use. Here is the code:
public UserDetails loadUserByUsername(String email) throws UsernameNotFoundException {
UsernamePasswordAuthenticationToken authentication = (UsernamePasswordAuthenticationToken) SecurityContextHolder.getContext().getAuthentication();
User user = (User) authentication.getPrincipal();
String username = user.getUsername();
if (username.equals(OAuth2Configuration.provider_app))
// Load from provider db
else if (username.equals(OAuth2Configuration.consumer_app))
// Load from consumer db
else
throw new UsernameNotFoundException("ClientID " + username + " not found.");
}
};
}
UsernamePasswordAuthenticationToken is used as /oauth/token is protected with Basic Oauth using the client id and secret.
I think you should be able to look inside SecurityContextHolder.getContext().getAuthentication.
This should be an instance of OAuth2Authentication, from which you can (after you cast) call getOAuth2Request() to get the original Oauth2Request details.
With this information you can have a single UserDetailsService that can delegate lookups to the correct db tables. You could use scopes or resourceIds to help determine what db table to use.
You could use the third option. but this is not a good principal to follow. you can send a custom param in the oauth/token end point. it can be accessed by AutoWiring HttpServletRequest in the userDetailsService.
UserDetailsService
#Autowired
private HttpServletRequest httpServletRequest;
#Override
public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
try {
String userType = httpServletRequest.getParameter("user_type");
LOGGER.info("Load user method \n Username : " + username + "\nuser_type : " + userType);
if (userType == null) {
throw new CustomOauthException("User type is required !");
}
if (userType.equals(String.valueOf(MOBILE_USER))) {
//get user..
} else if (userType.equals(String.valueOf(DRIVER))) {
//get driver..
} else if (userType.equals(String.valueOf(ADMIN))) {
//get admin
}
throw new CustomOauthException("User type is not valid !");
} catch (Exception e) {
e.printStackTrace();
LOGGER.error("Exception : " + e.getMessage());
throw new CustomOauthException(e.getMessage());
}
}

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