分布式04SpringCloudZuul三Fallback回退机制

Z时代
2024-01-10
分类：综合

1. 分布式04-Spring Cloud Zuul Api网关一

2. 分布式04-Spring Cloud Zuul 二 Zuul拦截器

回退机制只有针对于服务出现故障，Zuul做的一些后续操作。

代码

package com.cloud.config;
import org.springframework.cloud.netflix.zuul.filters.route.FallbackProvider;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
@Component
public class TestFallbackProvider implements FallbackProvider {
@Override
public String getRoute() {
//处理所有的服务
//        return "*";
        // 表明是为哪个微服务提供回退，*表示为所有微服务提供回退
return "eureka-server";
}
@Override
public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
//回退时的HTTP Status Code
return this.response(HttpStatus.NOT_FOUND);
}
private ClientHttpResponse response(final HttpStatus status) {
return new ClientHttpResponse() {
@Override
public HttpStatus getStatusCode() throws IOException {
return status;
}
@Override
public int getRawStatusCode() throws IOException {
return status.value();
}
@Override
public String getStatusText() throws IOException {
return status.getReasonPhrase();
}
@Override
public void close() {
            }
@Override
public InputStream getBody() throws IOException {
//回退操作
return new ByteArrayInputStream("eureka-server服务不可用，请稍后再试。".getBytes());
}
@Override
public HttpHeaders getHeaders() {
// headers设定
HttpHeaders headers = new HttpHeaders();
MediaType mt = new MediaType("application", "json", Charset.forName("UTF-8"));
headers.setContentType(mt);
                return headers;
}
        };
}
}

application.properties

zuul.routes.eureka-server.path=/public/*
zuul.routes.eureka-server.service-id=eureka-server
server.port= 12003
eureka.instance.hostname=localhost
eureka.client.service-url.defaultZone= http://${eureka.instance.hostname}:12000/eureka/
eureka.client.healthcheck.enabled=true
spring.application.name=eureka-Zuul

启动Zuul 和测试用的2个应用，打开Eureka，我们看到2个提供服务的应用eureka-server

eureka-server 提供一个返回端口的接口

/** * http://localhost:12001/public/getPort
 * @param pageable
* @return
* @throws Exception
 */
@RequestMapping(value = "/getPort", method = RequestMethod.GET )
public Msg getport(Pageable pageable, String operatorId) throws  Exception{
return Msg.MsgSuccess(port);
}