Adding extended error handling

application/module-language-school/src/main/java/org/fuseri/modulelanguageschool/exceptions/ApiError.java

+package org.fuseri.modulelanguageschool.exceptions;
+
+import com.fasterxml.jackson.annotation.JsonFormat;
+import lombok.Getter;
+import lombok.ToString;
+import org.springframework.http.HttpStatus;
+
+import java.time.Clock;
+import java.time.LocalDateTime;
+import java.util.List;
+
+@Getter
+@ToString
+class ApiError {
+
+    private HttpStatus status;
+    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd-MM-yyyy hh:mm:ss")
+    private LocalDateTime timestamp;
+    private String message;
+    private List<ApiSubError> subErrors;
+    private String path;
+
+    private ApiError() {
+        timestamp = LocalDateTime.now(Clock.systemUTC());
+    }
+
+    ApiError(HttpStatus status, Throwable ex, String path) {
+        this();
+        this.status = status;
+        this.path = path;
+        this.message = ex.getLocalizedMessage();
+    }
+
+    ApiError(HttpStatus status, List<ApiSubError> subErrors, Throwable ex, String path) {
+        this();
+        this.status = status;
+        this.subErrors = subErrors;
+        this.path = path;
+        this.message = ex.getLocalizedMessage();
+    }
+}

application/module-language-school/src/main/java/org/fuseri/modulelanguageschool/exceptions/ApiSubError.java

+package org.fuseri.modulelanguageschool.exceptions;
+
+public interface ApiSubError {
+}

application/module-language-school/src/main/java/org/fuseri/modulelanguageschool/exceptions/ApiValidationError.java

+package org.fuseri.modulelanguageschool.exceptions;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.ToString;
+
+@Data
+@EqualsAndHashCode(callSuper = false)
+@AllArgsConstructor
+@Getter
+@ToString
+class ApiValidationError implements ApiSubError {
+    private String object;
+    private String field;
+    private Object rejectedValue;
+    private String message;
+}

application/module-language-school/src/main/java/org/fuseri/modulelanguageschool/exceptions/RestResponseEntityExceptionHandler.java

+package org.fuseri.modulelanguageschool.exceptions;
+
+import jakarta.persistence.EntityNotFoundException;
+import jakarta.servlet.http.HttpServletRequest;
+import org.apache.commons.lang3.exception.ExceptionUtils;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.converter.HttpMessageNotReadableException;
+import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.util.UrlPathHelper;
+
+import java.util.List;
+
+@ControllerAdvice
+public class RestResponseEntityExceptionHandler {
+    private static final UrlPathHelper URL_PATH_HELPER = new UrlPathHelper();
+
+    /**
+     * Handle ResourceNotFoundException exceptions
+     *
+     * @param ex      exception
+     * @param request request
+     * @return response entity
+     */
+    @ExceptionHandler(value = {EntityNotFoundException.class})
+    public ResponseEntity<ApiError> handleNotFoundError(EntityNotFoundException ex, HttpServletRequest request) {
+        ApiError error = new ApiError(
+                HttpStatus.NOT_FOUND,
+                ex,
+                URL_PATH_HELPER.getRequestUri(request));
+        return buildResponseEntity(error);
+    }
+
+    /**
+     * Handle Validation exceptions
+     *
+     * @param ex      exception
+     * @param request request
+     * @return response entity
+     */
+    @ExceptionHandler(value = {MethodArgumentNotValidException.class, HttpMessageNotReadableException.class})
+    public ResponseEntity<ApiError> handleValidationErrors(MethodArgumentNotValidException ex, HttpServletRequest request) {
+        List<ApiSubError> subErrors = ex.getBindingResult().getFieldErrors()
+                .stream()
+                .map(e -> (ApiSubError) new ApiValidationError(e.getObjectName(), e.getField(), e.getRejectedValue(), e.getDefaultMessage()))
+                .toList();
+        ApiError error = new ApiError(
+                HttpStatus.BAD_REQUEST,
+                subErrors,
+                ex,
+                URL_PATH_HELPER.getRequestUri(request));
+        return buildResponseEntity(error);
+    }
+
+    /**
+     * Handle exceptions not matched by above handler methods
+     *
+     * @param ex      exception
+     * @param request request
+     * @return response entity
+     */
+    @ExceptionHandler({Exception.class})
+    public ResponseEntity<ApiError> handleAll(final Exception ex, HttpServletRequest request) {
+        final ApiError error = new ApiError(
+                HttpStatus.INTERNAL_SERVER_ERROR,
+                ExceptionUtils.getRootCause(ex),
+                URL_PATH_HELPER.getRequestUri(request));
+        return buildResponseEntity(error);
+    }
+
+    private ResponseEntity<ApiError> buildResponseEntity(ApiError apiError) {
+        return new ResponseEntity<>(apiError, apiError.getStatus());
+    }
+}