通过这篇文章来看看spring Cloud在代码中的具体应用，以及配置和注解；

Eureka

一、erueka 客户端配置

1、Eureka 启禁用

eureka.client.enabled=true

2、Eureka 连接超时时间

eureka.client.eureka-server-connect-timeout-seconds=5

eureka.client.eureka-connection-idle-timeout-seconds=30

3、Eureka Server等待超时时间

eureka.client.eureka-server-read-timeout-seconds=8

4、拉取Eureka注册信息

eureka.client.fetch-registry=true

5、注册自身到Eureka

eureka.client.register-with-eureka=true

6、过滤状态存活的实例

eureka.client.filter-only-up-instances=true

7、注册实例的名称

eureka.instance.appname=unknown

8、健康检查相对路径

eureka.instance.health-check-url-path=/health

9、HOME页面相对路径

eureka.instance.home-page-url-path=/

10、服务续约到期时间

eureka.instance.lease-expiration-duration-in-seconds=90

11、服务续约间隔时间

eureka.instance.lease-renewal-interval-in-seconds=30

12、注册元数据

eureka.instance.metadata-map=

13、通过配置文件找到namespace，忽略springcloud的配置

eureka.instance.namespace=

14、注册是否显示IP地址（第一个非回环地址）

eureka.instance.prefer-ip-address=false

15、注册时使用的IP地址

eureka.instance.ip-address=

16、压缩Eureka Server的数据

eureka.client.g-zip-content=true

17、心跳执行器的线程池初始值

eureka.client.heartbeat-executor-thread-pool-size=2

18、最初复制实例信息到Eureka服务器所需的时间

eureka.client.initial-instance-info-replication-interval-seconds=40

19、同步实例变更信息到Eureka服务到周期

eureka.client.instance-info-replication-interval-seconds=30

20、从Eureka服务器拉取服务信息周期

eureka.client.registry-fetch-interval-seconds=30

21、Eureka Server地址

eureka.client.serviceUrl.defaultZone=xxx,xxx,xxx

二、eureka 服务端配置

1、注册实例

eureka.instance.registry.default-open-for-traffic-count=1

eureka.instance.registry.expected-number-of-renews-per-min=1

2、服务面板

eureka.dashborad.enabled=true

eureka.dashboard.path=/

3、自我保护

eureka.server.enable-self-preservation: true
eureka.server.eviction-interval-timer-in-ms: 60000

eureka.server.renewal-percent-threshold: 0.85

4、限流

eureka.server.rate-limiter-enabled: false
eureka.server.rate-limiter-throttle-standard-clients: false
eureka.server.rate-limiter-burst-size: 10
eureka.server.rate-limiter-full-fetch-average-rate: 100

eureka.server.rate-limiter-registry-fetch-average-rate: 500

5、相应缓存

eureka.server.response-cache-auto-expiration-in-seconds: 180
eureka.server.response-cache-update-interval-ms: 30000

eureka.server.use-read-only-response-cache: true

6、安全校验

#启用安全校验

security.basic.enabled=true
#授权用户名
security.user.name=root
#授权密码

security.user.password=123456

三、高可用配置

1、节点数据同步

eureka.server.batch-replication: false

eureka.enable-replicated-request-compression: false

2、同步线程池

eureka.server.min-threads-for-status-replication: 1
eureka.server.max-threads-for-status-replication: 1
eureka.server.max-idle-thread-in-minutes-age-for-status-replication: 10
eureka.server.min-threads-for-peer-replication: 5
eureka.server.max-threads-for-peer-replication: 20
eureka.server.max-idle-thread-age-in-minutes-for-peer-replication: 15

eureka.server.number-of-replication-retries: 5

3、定时任务

eureka.server.peer-eureka-status-refresh-time-interval-ms: 3000
eureka.server.peer-eureka-nodes-update-interval-ms: 600000

eureka.server.min-available-instances-for-peer-replication: -1

4、连接

eureka.server.peer-node-total-connections-per-host: 500
eureka.server.peer-node-total-connections: 1000
eureka.server.peer-node-read-timeout-ms: 200
eureka.server.peer-node-connect-timeout-ms: 200

eureka.server.peer-node-connection-idle-timeout-seconds: 30

5、重置注册

eureka.server.registry-sync-retries: 0
eureka.server.registry-sync-retry-wait-ms: 30000

Feign

使用及配置url: SpringCloud：Feign的使用及配置_feignclient配置_Poetry-Distance的博客-CSDN博客

Hystrix

使用及配置的url: Hystrix使用及其配置详解_hystrix配置_李子捌的博客-CSDN博客

@RestController
@RequestMapping("/circuitBreaker")
public class CircuitBreakConfigController {
    @GetMapping
    @HystrixCommand(
            fallbackMethod = "fallback",
            commandProperties = {
                    @HystrixProperty(
                            name = "execution.isolation.thread.timeoutInMilliseconds",
                            value = "1000"
                    ),
                    @HystrixProperty(
                            name = "circuitBreaker.requestVolumeThreshold",
                            value = "4"
                    ),
                    @HystrixProperty(
                            name = "circuitBreaker.errorThresholdPercentage",
                            value = "50"
                    ),
                    @HystrixProperty(
                            name = "metrics.rollingStats.timeInMilliseconds",
                            value = "60000"
                    ),
                    @HystrixProperty(
                            name = "circuitBreaker.sleepWindowInMilliseconds",
                            value = "60000"
                    )
            })
    public ResponseEntity<String> demo() {
        try {
            // 模拟接口请求
            TimeUnit.SECONDS.sleep(2);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return new ResponseEntity<>("Hello!", HttpStatus.OK);
    }
    private ResponseEntity<String> fallback() {
        return new ResponseEntity<>("Timeout!", HttpStatus.OK);
    }
}