[MSA] Spring Cloud로 MSA를 개발해보자 3편 [Gateway Service-2]

1. CustomFilter

[gateWay-service] CustomFilter.java

@Component
@Slf4j
public class CustomFilter extends AbstractGatewayFilterFactory<CustomFilter.Config> {
    public CustomFilter() {
        super(Config.class);
    }

    @Override
    public GatewayFilter apply(Config config) {
        // Custom Pre Filter

        return (exchange, chain) -> {
            ServerHttpRequest request = exchange.getRequest();
            ServerHttpResponse response = exchange.getResponse();

            log.info("Custom PRE filter : request id -> {}", request.getId());

            // Custom Post Filter
            return chain.filter(exchange).then(Mono.fromRunnable(() -> {
                log.info("Custom POST filter : response code -> {}", response.getStatusCode());
            }));
        };
    }

    public static class Config {
        // Put the configuration properties
    }

}

 

[gateWay-service]  application.yml

server:
  port: 8000

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka

spring:
  application:
    name: apigateway-service
  cloud:
    gateway:
      routes:
        - id: first-service
          uri: http://localhost:8081/
          predicates:
            - Path=/first-service/**
          filters:
#            - AddRequestHeader=first-request, first-request-header2
#            - AddResponseHeader=first-Response, first-Response-header2
			- CustomFilter
        - id: second-service
          uri: http://localhost:8082/
          predicates:
            - Path=/second-service/**
          filters:
#            - AddRequestHeader=second-request, second-request-header2
#            - AddResponseHeader=second-Response, second-Response-header2
			- CustomFilter

 

[first-service] FirstServiceController.java

@GetMapping("/check")
    public String check(HttpServletRequest request) {
        log.info("Server port={}", request.getServerPort());
        return String.format("Hi, there. This is a message from First Service on PORT %s"
                , env.getProperty("local.server.port"));
    }

 

테스트 :

2.GlobalFilter

[gateWay-Service] GlobalFilter.java

@Component
@Slf4j
public class GlobalFilter extends AbstractGatewayFilterFactory<GlobalFilter.Config> {
    public GlobalFilter() {
        super(Config.class);
    }

    @Override
    public GatewayFilter apply(Config config) {
        // Custom Pre Filter

        return (exchange, chain) -> {
            ServerHttpRequest request = exchange.getRequest();
            ServerHttpResponse response = exchange.getResponse();

            log.info("Global Filter baseMessage: {}", config.getBaseMessage());

            if (config.isPreLogger()) {
                log.info("Global Filter start: request id -> {}", request.getId());
            }
            // Custom Post Filter
            return chain.filter(exchange).then(Mono.fromRunnable(() -> {
                if (config.isPostLogger()) {
                    log.info("Global Filter End: response code -> {}", response.getStatusCode());
                }
            }));
        };
    }

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

}

 

[gateWay-Service] application.yml

server:
  port: 8000

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka

spring:
  application:
    name: apigateway-service
  cloud:
    gateway:
      default-filters: // 추가
       - name: GlobalFilter
         args:
           baseMessage: Spring Cloud Gateway Global Filter
           preLogger: true
           postLogger: true
      routes:
        - id: first-service
          uri: http://localhost:8081/
          predicates:
            - Path=/first-service/**
          filters:
#            - AddRequestHeader=first-request, first-request-header2
#            - AddResponseHeader=first-Response, first-Response-header2
			- CustomFilter
        - id: second-service
          uri: http://localhost:8082/
          predicates:
            - Path=/second-service/**
          filters:
#            - AddRequestHeader=second-request, second-request-header2
#            - AddResponseHeader=second-Response, second-Response-header2
			- CustomFilter

테스트 :

3. LoggingFilter

[gateWay-Service] LoggingFilter.java

package com.example.apigateway_service.filter;

import lombok.Data;
import lombok.extern.slf4j.Slf4j;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.OrderedGatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.core.Ordered;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import reactor.core.publisher.Mono;

@Component
@Slf4j
public class LoggingFilter extends AbstractGatewayFilterFactory<LoggingFilter.Config> {
    public LoggingFilter() {
        super(Config.class);
    }

    @Override
    public GatewayFilter apply(Config config) {
        // Custom Pre Filter

//        return (exchange, chain) -> {
//            ServerHttpRequest request = exchange.getRequest();
//            ServerHttpResponse response = exchange.getResponse();
//
//            log.info("Global Filter baseMessage: {}", config.getBaseMessage());
//
//            if (config.isPreLogger()) {
//                log.info("Global Filter start: request id -> {}", request.getId());
//            }
//            // Custom Post Filter
//            return chain.filter(exchange).then(Mono.fromRunnable(() -> {
//                if (config.isPostLogger()) {
//                    log.info("Global Filter End: response code -> {}", response.getStatusCode());
//                }
//            }));
//        };

        GatewayFilter filter = new OrderedGatewayFilter((exchange, chain) -> {
            ServerHttpRequest request = exchange.getRequest();
            ServerHttpResponse response = exchange.getResponse();

            log.info("Logging Filter baseMessage: {}", config.getBaseMessage());

            if (config.isPreLogger()) {
                log.info("Logging PRE Filter: request id -> {}", request.getId());
            }
            // Custom Post Filter
            return chain.filter(exchange).then(Mono.fromRunnable(() -> {
                if (config.isPostLogger()) {
                    log.info("Global POST Filter: response code -> {}", response.getStatusCode());
                }
            }));
        }, Ordered.LOWEST_PRECEDENCE);

        return filter;
    }

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

}

 

[gateWay-Service] application.yml

server:
  port: 8000

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka

spring:
  application:
    name: apigateway-service
  cloud:
    gateway:
      default-filters: // 추가
       - name: GlobalFilter
         args:
           baseMessage: Spring Cloud Gateway Global Filter
           preLogger: true
           postLogger: true
      routes:
        - id: first-service
          uri: http://localhost:8081/
          predicates:
            - Path=/first-service/**
          filters:
			- CustomFilter
        - id: second-service
          uri: http://localhost:8082/
          predicates:
            - Path=/second-service/**
          filters:
			- name: CustomFilter
            - name: LoggingFilter
              args:
                baseMessage: Hi, there.
                preLogger: true
                postLogger: true

 

테스트 : 

 

4. Load Balancer

 

1). eureka 등록

first-service, second-service -> application.yml

( first-service, second-service, gateWay-service false -> true 변경)

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka

 

2). routes uri 로드밸런서 설정

[gateWay-service] application.yml

server:
  port: 8000

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka

spring:
  application:
    name: apigateway-service
  cloud:
    gateway:
      default-filters:
        - name: GlobalFilter
          args:
            baseMessage: Spring Cloud Gateway Global Filter
            preLogger: true
            postLogger: true
      routes:
        - id: first-service
         // first-service -> application.yml -> spring:application:name로 변경
          uri: lb://MY-FIRST-SERVICE
          predicates:
            - Path=/first-service/**
          filters:
            - CustomFilter
        - id: second-service
        // second-service -> application.yml -> spring:application:name로 변경
          uri: lb://MY-SECOND-SERVICE
          predicates:
            - Path=/second-service/**
          filters:
            - name: CustomFilter
            - name: LoggingFilter
              args:
                baseMessage: Hi, there.
                preLogger: true
                postLogger: true

 

3). 랜덤포트 설정

[first-service] application.yml

server:
  port: 0 // 0번이 랜덤포트

spring:
  application:
    name: my-first-service

eureka:
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://localhost:8761/eureka
  instance:
  	// 이거 없으면 여러개 실행시켜도 1개로만 표시됨
    instance-id: ${spring.application.name}:${spring.application.instance_id:${random.value}}

 

4). 로드밸런스 테스트

[1] first-service application.java 실행
[2] 터미널 : mvn spring-boot:run

 

 

포스트맨에서 실행 할 때마다 4432 포트와 4829 포트가 번갈아 가며 작동된다