目标

开启zuul重试机制
配置Ribbon
配置hystrix

zuul本身已经引入了对Ribbon、hystrix的依赖，因此无需再次引入

修改配置

# 端口号
server.port=6001

# 服务名
spring.application.name=api

zuul.routes.account.path=/account/**
zuul.routes.account.serviceId=account

zuul.routes.wallet.path=/wallet/**
zuul.routes.wallet.serviceId=wallet

# 开启重试机制
zuul.retryable=true

# eureka服务注册中心地址
eureka.client.serviceUrl.defaultZone=http://localhost:5000/eureka/

hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds=10000

ribbon.ConnectTimeout=3000
ribbon.ReadTimeout=3000
ribbon.OkToRetryOnAllOperations=true
ribbon.MaxAutoRetries=1
ribbon.MaxAutoRetriesNextServer=1

增加ZuulFallBack类

@Component
public class ZuulFallBack implements FallbackProvider {
    @Override
    public String getRoute() {
        return "*";
    }

    public ClientHttpResponse build(String message) {
        return new ClientHttpResponse() {

            @Override
            public InputStream getBody() throws IOException {
                return new ByteArrayInputStream(message.getBytes("UTF-8"));
            }

            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders headers = new HttpHeaders();
                //和body中的内容编码一致，否则容易乱码
                headers.setContentType(MediaType.APPLICATION_JSON_UTF8);
                return headers;
            }

            /**
             * 网关向api服务请求是失败了，但是消费者客户端向网关发起的请求是OK的，
             * 不应该把api的404,500等问题抛给客户端
             * 网关和api服务集群对于客户端来说是黑盒子
             */
            @Override
            public HttpStatus getStatusCode() throws IOException {
                return HttpStatus.OK;
            }

            @Override
            public int getRawStatusCode() throws IOException {
                return HttpStatus.OK.value();
            }

            @Override
            public String getStatusText() throws IOException {
                return HttpStatus.OK.getReasonPhrase();
            }

            @Override
            public void close() {

            }

        };
    }

    @Override
    public ClientHttpResponse fallbackResponse() {
        return build("gateway fall back");
    }

    @Override
    public ClientHttpResponse fallbackResponse(Throwable cause) {
        return build(cause.getCause().getMessage());
    }
}