API Gateway Service

• API Gateway Service
  • API Gateway Service
  • Netflix Ribbon
  • Netflix Zuul 구현
  • Spring Cloud Gateway – 기본
  • Spring Cloud Gateway – Filter
  • Spring Cloud Gateway – Custom Filter
  • Spring Cloud Gateway – Global Filter
  • Spring Cloud Gateway – Custom Filter (Logging)
  • Spring Cloud Gateway – Eureka 연동
  • Spring Cloud Gateway – Load Balancer

API Gateway Service

• 인증 및 권한 부여
• 서비스 검색 통합
• 응답 캐싱
• 정책, 회로 차단기 및 QoS 다시 시도
• 속도 제한
• 부하 분산
• 로깅, 추적, 상관 관계
• 헤더, 쿼리 문자열 및 청구 변환
• IP 허용 목록에 추가
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Netflix Ribbon

• Spring Cloud에서의 MSA간 통신
  • RestTemplate
    • RestTemplate restTemplate = new RestTemplate(); restTemplate.getForObject(“http://localhost:8080", User.class, 200);
  • Feign Client
    • @FeignClient(“stores”) @RequestMapping(method = RequestMethod.GET, value = “/stores”) List getStores(); List getStores();
• Ribbon: Client side Load Balancer
  • 서비스 이름으로 호출
  • Health Check
  • Spring Cloud Ribbon은 Spring Boot 2.4에서 Maintenance상태
    • Maintenance상태 : 새로운 기능을 추가 하지 않는다
  • 비동기 처리 방식이 안 돼서 최근에는 잘 사용하지 않는다
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Netflix Zuul 구현

• 구성
  • First Service
  • Second Service
  • Netflix Zuul - Gateway
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• Spring Cloud Zuul은 Spring Boot 2.4에서 Maintenance상태
  • https://spring.io/blog/2018/12/12/spring-cloud-greenwich-rc1-available-now#spring-cloud-netflix-projects-entering-maintenance-mode
• Step1) First Service, Second Service
  • Spring Boot: 2.3.8
  • Dependencies: Lombok, Spring Web, Eureka Discovery Client
• Step2) First Service, Second Service
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• Step3) Test
• Step4) Zuul Service
  • Spring Boot: 2.3.8
  • Dependencies: Lombok, Spring Web, Zuul
• Step5) Zuul Service
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• Step6) ZuulFilter
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Spring Cloud Gateway – 기본

• 비동기 처리 방식이 가능하다
• Netty 서버가 동작
• Step1) Dependencies
  • DevTools, Eureka Discovery Client, Gateway
• Step2) application.properties (or application.yml)
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• Step3) Test

Spring Cloud Gateway – Filter

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• Step4) Filter using Java Code – FilterConfig.java
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• Step4) Filter using Java Code – FirstServiceController.java, SecondServiceController.java
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• Step4) Test
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• Step5) Filter using Property – application.yml
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• Step5) Test
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Spring Cloud Gateway – Custom Filter

• Step6) Custom Filter – CustomFilter.java
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• Step6) Custom Filter – application.yml
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• Step6) Custom Filter – FirstServiceController.java, SecondServiceController.java
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Spring Cloud Gateway – Global Filter

• Step7) Global Filter – GlobalFilter.java
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• Step7) Global Filter – application.yml
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• Step7) Global Filter – Test
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Spring Cloud Gateway – Custom Filter (Logging)

• Step8) Logging Filter – LoggingFilter.java
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• Step8) Logging Filter – application.yml
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• Step8) Logging Filter – Test
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Spring Cloud Gateway – Eureka 연동

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• Step1) Eureka Client 추가 – pom.xml, application.yml
  • Spring Cloud Gateway, First Service, Second Service
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• Step2) Eureka Client 추가 –application.yml
  • Spring Cloud Gateway
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• Step3) Eureka Server – Service 등록 확인
  • Spring Cloud Gateway, First Service, Second Service
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Spring Cloud Gateway – Load Balancer

• Step4) First Service, Second Service를각각2개씩기동
  1. VM Options à-Dserver.port=[다른포트]
  2. mvn spring-boot:run -Dspring-boot.run.jvmArguments=’-Dserver.port=9003’
  3. mvn clean compile package $ java -jar -Dserver.port=9004 ./target/user-service-0.0.1-SNAPSHOT.jar
• Step5) Eureka Server – Service 등록확인
• Step6) Random port 사용
  • Spring Cloud Gateway, First Service, Second Service
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• Step6) Post 확인 – FirstController.java
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• Step6) Random port 사용
  • Spring Cloud Gateway, First Service, Second Service
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