微服务Zuul网关实现服务降级-蒲公英云

微服务Zuul网关实现服务降级

spring boot版本：2.1.10.RELEASE

1、项目搭建

所需依赖及项目的搭建请参考上一篇博客微服务中网关的作用及搭建

2、添加fallback的bean

在spring boot 2.0之前实现的是 ZuulFallbackProvider接口，但是在spring boot 2.0之后实现的是 FallbackProvider 接口。

package com.ebook.zuul.fallback;
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;
/**
 * @author:JZ
 * @date:2020/1/28
 */
@Component
public class ProductFallbackProvider implements FallbackProvider {
    /**
     * 返回的是服务的路由，即服务的名称，
     * 代表为哪个服务提供fallback
     * @return
     */
    @Override
    public String getRoute() {
        return "ebook-product-core";
    }
    @Override
    public ClientHttpResponse fallbackResponse(String route, Throwable cause) {
        return new ClientHttpResponse() {
            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders header = new HttpHeaders();
                MediaType mt = new MediaType("application", "json", Charset.forName("UTF-8"));
                header.setContentType(mt);
                return header;
            }
            @Override
            public InputStream getBody() throws IOException {
                String input="商品服务不可用，请联系管理员！";
                return new ByteArrayInputStream(input.getBytes());
            }
            @Override
            public HttpStatus getStatusCode() throws IOException {
                //HttpResponse的fallback的状态码,HttpStatus值
                return HttpStatus.OK;
            }
            @Override
            public int getRawStatusCode() throws IOException {
                //HttpResponse的fallback的状态码,int值
                return this.getStatusCode().value();
            }
            @Override
            public String getStatusText() throws IOException {
                //HttpResponse的fallback的状态码,string
                return this.getStatusCode().getReasonPhrase();
            }
            @Override
            public void close() {
            }
        };
    }
}