CommonExceptionHandler.java

package com.checkout.payment.gateway.exception;

import com.checkout.payment.gateway.model.ErrorResponse;
import io.github.resilience4j.circuitbreaker.CallNotPermittedException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;

@ControllerAdvice
public class CommonExceptionHandler {

    private static final Logger LOG = LoggerFactory.getLogger(CommonExceptionHandler.class);

    @ExceptionHandler(EventProcessingException.class)
    public ResponseEntity<ErrorResponse> handleEventProcessingException(EventProcessingException ex) {
        LOG.error("Payment not found", ex);
        return new ResponseEntity<>(new ErrorResponse(ex.getMessage()), HttpStatus.NOT_FOUND);
    }

    @ExceptionHandler(BankServiceException.class)
    public ResponseEntity<ErrorResponse> handleBankServiceException(BankServiceException ex) {
        LOG.error("Bank service error", ex);
        return new ResponseEntity<>(
                new ErrorResponse("Payment processing failed: bank service unavailable"),
                HttpStatus.BAD_GATEWAY);
    }

    @ExceptionHandler(IdempotencyConflictException.class)
    public ResponseEntity<ErrorResponse> handleIdempotencyConflict(IdempotencyConflictException ex) {
        LOG.warn("Idempotency conflict: {}", ex.getMessage());
        return new ResponseEntity<>(new ErrorResponse(ex.getMessage()), HttpStatus.CONFLICT);
    }

    @ExceptionHandler(RateLimitExceededException.class)
    public ResponseEntity<ErrorResponse> handleRateLimit(RateLimitExceededException ex) {
        LOG.warn("Rate limit exceeded: {}", ex.getMessage());
        return new ResponseEntity<>(new ErrorResponse(ex.getMessage()), HttpStatus.TOO_MANY_REQUESTS);
    }

    @ExceptionHandler(CallNotPermittedException.class)
    public ResponseEntity<ErrorResponse> handleCircuitOpen(CallNotPermittedException ex) {
        LOG.warn("Circuit breaker open for bank client");
        return new ResponseEntity<>(
                new ErrorResponse("Bank temporarily unavailable (circuit open)"),
                HttpStatus.SERVICE_UNAVAILABLE);
    }
}