feat: filter에서 TokenInValidateException 에 대한 응답 json생성 하도록 처리 (#35)

BE/src/main/java/org/team4/airbnb/filter/AuthCheckFilter.java

@@ -1,6 +1,9 @@
 package org.team4.airbnb.filter;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import javax.servlet.FilterChain;
 import javax.servlet.ServletException;
 import javax.servlet.annotation.WebFilter;
@@ -9,8 +12,10 @@
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
 import org.springframework.web.filter.OncePerRequestFilter;
 import org.team4.airbnb.auth.JwtTokenProvider;
+import org.team4.airbnb.exception.ErrorResponse;
 import org.team4.airbnb.exception.TokenInValidateException;
 
 @Slf4j
@@ -25,18 +30,32 @@ protected void doFilterInternal(HttpServletRequest request, HttpServletResponse
 		FilterChain filterChain) throws ServletException, IOException {
 		String header = request.getHeader(HttpHeaders.AUTHORIZATION);
 
-		validateHeader(header);
-		String accessToken = header.substring("Bearer ".length());
+		try {
+			validateHeader(header);
+			String accessToken = header.substring("Bearer ".length());
 
-		jwtTokenProvider.validateJwtToken(accessToken);
+			jwtTokenProvider.validateJwtToken(accessToken);
 //		Claims claims = jwtTokenProvider.parseJwtToken(accessToken);
 
-		filterChain.doFilter(request, response);
+			filterChain.doFilter(request, response);
+		} catch (TokenInValidateException e) {
+			ErrorResponse errorResponse = new ErrorResponse(new String("invalid token".getBytes(),StandardCharsets.UTF_8));
+			response.setStatus(HttpStatus.UNAUTHORIZED.value());
+			response.getWriter().write(convertObjectToJson(errorResponse));
+		}
 	}
 
-	private void validateHeader(String header) {
+	private void validateHeader(String header) throws TokenInValidateException {
 		if (header == null || !header.startsWith("Bearer ")) {
 			throw new TokenInValidateException();
 		}
 	}
+
+	private String convertObjectToJson(Object object) throws JsonProcessingException {
+		if (object == null) {
+			return null;
+		}
+		ObjectMapper mapper = new ObjectMapper();
+		return mapper.writeValueAsString(object);
+	}
 }