# README

## 1. Monolithic to Microservice

* Monolithic 구조에서 Microservice 구조로 바뀜    
* 사용자가 모든 서비스로 개별 접속 할수는 없음  
* [Netflix 사례](https://github.com/SDSACT/coe-guide/blob/master/README2.md#1-netflix-oss)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYyJkx8VK4uxNBRojk%2F-LGYyKdLMWT4afd52syP%2Fmonolith2msa.png?generation=1530685645251550\&alt=media)

## 2. Service Discovery

* Service를 eureka에 등록 하여 id 기반으로 endpoint 탐색이 가능하게 함  
* Auto scaling에 유연하게 대처할 수 있음  
* [Eureka 동작 방식](https://github.com/SDSACT/coe-guide/blob/master/Service%20Discovery/Eureka_2.md#eureka%EA%B8%B0%EB%8A%A5)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYzzImdEx_R2L1KI30%2F-LGYyKdRltmFrCBIxEcQ%2Feureka.png?generation=1530686078756647\&alt=media)

## 3. Client Load Balancing

* 여러 instances에 대해 loadbalancing이 가능  
* [Ribbon](https://github.com/SDSACT/coe-guide/blob/master/README2.md#4-ribbon)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYyJkx8VK4uxNBRojk%2F-LGYyKdXg8SVUxqbl_3Q%2Fribbon.png?generation=1530685647525165\&alt=media)

## 4. Gateway

* Zuul을 gateway로 사용하여 하나의 인입점을 만듦
* Zuul이 모든 요청을 관련 서비스에게 routing 함    
* [Zuul](https://github.com/SDSACT/coe-guide/blob/master/Gateway/Zuul_2.md#zuul-%EC%9D%B4%EB%9E%80)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYzzImdEx_R2L1KI30%2F-LGYyKdPWVV4BVLtS4na%2Fzuul.png?generation=1530686078656473\&alt=media)

## 5. Inner Service Call

* Feign을 사용하여 다른 서비스 호출을 쉽게 할 수 있음  
* [Feign](https://github.com/SDSACT/coe-guide/blob/master/Etc/Feign.md#client-api-call)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYyJkx8VK4uxNBRojk%2F-LGYyKdTvWoC8YT0OgRL%2Finner-service-call.png?generation=1530685661035828\&alt=media)

## 6. Circuit Breaker

* 하위 서비스 장애 상황시 장애가 상위로 전파되는것을 방지 함  
* Fallback을 통해 장애시 미리 정의된 값으로 처리 할 수 있음  
* [Hystrix](https://github.com/SDSACT/coe-guide/blob/master/Circuit%20Breaker/Hystrix.md#hystrix%EB%9E%80)
* [Hystrix 동작 방식](https://github.com/SDSACT/coe-guide/blob/master/README2.md#53-%ED%9A%8C%EB%A1%9C-%EC%B0%A8%EB%8B%A8%EA%B8%B0-circuit-breaker)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYyJkx8VK4uxNBRojk%2F-LGYyKdZ3OFfAh8zdm1X%2Fhystrix.png?generation=1530685648944794\&alt=media)

## 7. Distributed Log Tracking

* Sleuth를 사용하여 분산 환경에서 로그 추적을 쉽게 할 수 있음     
* [Sleuth](https://github.com/SDSACT/coe-guide/blob/master/Log/Sleuth.md#sleuth-%EB%9E%80)

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYyJkx8VK4uxNBRojk%2F-LGYyKdVGS1EHt-Op4zj%2Fsleuth.png?generation=1530685646329387\&alt=media)

## 8. Ribbon and Hystrix on Zuul

* Ribbon, Hystrix는 zuul에도 적용 가능    

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYyJkx8VK4uxNBRojk%2F-LGYyKdaEYbKqGCxcCws%2Fribbon-zuul.png?generation=1530685648192235\&alt=media)

## 9. Config Server

* 서비스들의 config를 통합 관리할 수 있음
* Config 변경 내용 무중단 반영 가능  

![](https://1967639135-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LE8_fwLnI2gUuguYTDU%2F-LGYzzImdEx_R2L1KI30%2F-LGYyKdcFq52zVl9PLHN%2Fconfigserver.png?generation=1530686078703986\&alt=media)

## Circuit Breaker

* Hystrix

## Config

* SpringCloudConfig

## Gateway

* Zuul

## Load Balancing

* Ribbon

## Log

* Sleuth
* EFK

## Messaging

* RabbitMQ
* Kafka

## Monitoring

* Spring Boot Admin

## Service Discovery

* Eureka

## Sidecar Pattern

* SpringCloudNetflixSidecar

## Tracing

* Pinpoint
* Elastic APM

## Etc

* Feign