revised exception handling for empty fields.

backend/src/main/java/com/vaessl/app/exception/GlobalExceptionHandler.java

@@ -1,6 +1,7 @@
 package com.vaessl.app.exception;
 
 import org.springframework.http.ProblemDetail;
+import org.springframework.validation.FieldError;
 import org.springframework.web.bind.MethodArgumentNotValidException;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
@@ -10,13 +11,18 @@ import org.springframework.web.client.ResourceAccessException;
 
 import static com.vaessl.app.exception.ErrorMessage.*;
 
+import java.util.stream.Collectors;
+
 @RestControllerAdvice
 public class GlobalExceptionHandler {
 
     @ExceptionHandler(MethodArgumentNotValidException.class)
     public ProblemDetail handleEmptyCredentialInput(MethodArgumentNotValidException e) {
+
+        String defaultMessages = e.getBindingResult().getFieldErrors().stream().map(FieldError::getDefaultMessage).collect(Collectors.joining(", "));
+
         return ProblemDetail.forStatusAndDetail(BAD_REQUEST_EMPTY_FIELDS.getStatus(),
-                BAD_REQUEST_EMPTY_FIELDS.getMessage());
+                BAD_REQUEST_EMPTY_FIELDS.getMessage() + " [" + defaultMessages + "]");
     }
 
     @ExceptionHandler(HttpClientErrorException.Unauthorized.class)
@@ -41,8 +47,9 @@ public class GlobalExceptionHandler {
                         SERVER_ERROR_GENERAL.getMessage() + e.getStatusText());
     }
 
-    @ExceptionHandler(ProviderNotFoundException.class)
-    public ProblemDetail handleWrongServiceType(ProviderNotFoundException e) {
-        return ProblemDetail.forStatusAndDetail(WRONG_SERVICE_TYPE.getStatus(), WRONG_SERVICE_TYPE.getMessage());
+    @ExceptionHandler(EmptyCredentialsException.class)
+    public ProblemDetail handleEmptyCredentials(EmptyCredentialsException e) {
+        return ProblemDetail.forStatusAndDetail(BAD_REQUEST_EMPTY_FIELDS.getStatus(),
+                BAD_REQUEST_EMPTY_FIELDS.getMessage() + " " + e.getMissingFields());
     }
 }