[Spring] Spring Cloud Gateway + GlobalFilter

[ 설정파일 ]

spring:
  cloud:
    gateway:
      default-filters:
        - DedupeResponseHeader=Access-Control-Allow-Origin Access-Control-Allow-Credentials, RETAIN_UNIQUE
        - name: GlobalFilter
          args:
            baseMessage: Base Message
            preLogger: true
            postLogger: true
      globalcors:
        corsConfigurations:
          '[/**]':
            add-to-simple-url-handler-mapping: true
            allowedOrigins:
              - http://localhost:8081
            allow-credentials: true
            allowedMethods:
              - GET
              - POST
              - DELETE
              - PUT
              - OPTIONS
      routes:
        - id: service1
          uri: http://localhost:8080
          predicates:
            - Path=/api/service1/**
        - id: service2
          uri: http://localhost:8082
          predicates:
            - Path=/api/service2/**
          filters:
            - AddRequestHeader=META-TOKEN, A1B2C3D4E5
            - RewritePath=/api/service2/(?<segment>/?.*), /api/$\{segment}  # /api/service2/auth/login -> /api/auth/login

[ Global Filter ]

@Component
public class GlobalFilter extends AbstractGatewayFilterFactory<GlobalFilter.Config> {

    @Autowired
    private JwtProvider jwtProvider;

    public GlobalFilter() {
        super(Config.class);
    }

    @Override
    public GatewayFilter apply(Config config) {
        return (((exchange, chain) -> {
            ServerHttpRequest request = exchange.getRequest();

            // is exist token
            if (!request.getHeaders().containsKey(HttpHeaders.AUTHORIZATION)) {
                return onError(exchange, "Not found authorization header");
            }

            // validate token
            String authorization = Objects.requireNonNull(request.getHeaders().get(HttpHeaders.AUTHORIZATION)).get(0);
            String token = authorization.replace("Bearer", "").trim();

            if (!jwtProvider.isValidToken(token)) {
                return onError(exchange, "JWT is not valid");
            }

            return chain.filter(exchange);
        }));
    }

    private Mono<Void> onError(ServerWebExchange exchange, String message) {
        ServerHttpResponse response = exchange.getResponse();
        response.setStatusCode(HttpStatus.UNAUTHORIZED);

        return response.setComplete();
    }

    @Data
    public static class Config {
        private String baseMessage;
        private boolean preLogger;
        private boolean postLogger;
    }
}