【Java】SpringCloud之Zuul

Z时代
2024-01-10
分类：技术分享

【前面的话】书接上文，前面已经讲过了SpringCloud的注册中心Eureka、Ribbon和Feign等等，如果有不清楚的也可以去看看我的微服务系列文章。这篇文章我要说的是微服务中的网关。

壹、Zuul的简介

Zuul的主要功能是路由转发和过滤器。路由功能是微服务的一部分，比如／api/user转发到到user服务，/api/shop转发到到shop服务。zuul默认和Ribbon结合实现了负载均衡的功能。

zuul有以下功能：

Authentication Insights Stress Testing Canary Testing Dynamic Routing Service Migration Load Shedding Security Static Response handling Active/Active traffic management

贰、准备工作

新建一个feign子工程lovin-cloud-zuul，用于后面的操作。下面是主要的pom依赖:

<parent>
<artifactId>lovincloud</artifactId>
<groupId>com.eelve.lovincloud</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>lovin-cloud-zuul</artifactId>
<packaging>jar</packaging>
<name>lovincloudzuul</name>
<version>0.0.1</version>
<description>zuul</description>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zuul</artifactId>
<version>1.4.7.RELEASE</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
<version>2.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins></build>

这里为了安全，我这里还是添加spring-boot-starter-security，同时配置路由规则发送/api-ribbon/打头开始的服务转发到lovinribbonclient而发送/api-feign/打头的服务转发到lovinfeignclient，可以看出这里是配置相应的路由规则。

server: port: 8882 # 服务端口号 spring: application: name: lovincloudzuul # 服务名称 security: basic: enabled: true user: name: lovin password: ${REGISTRY_SERVER_PASSWORD:lovin} zuul: routes: api-ribbon: path: /api-ribbon/** serviceId: lovinribbonclient api-feign: path: /api-feign/** serviceId: lovinfeignclient eureka: client: serviceUrl: defaultZone: http://lovin:[email protected]:8881/eureka/ # 注册到的eureka服务地址 instance: leaseRenewalIntervalInSeconds: 10 health-check-url-path: /actuator/health metadata-map: user.name: lovin

user.password: lovin

配置spring-boot-starter-security，这里为了方便我这里放开所有请求

package com.eelve.lovin.config;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
/**
* @ClassName WebSecurityConfig
* @Description TDO
* @Author zhao.zhilue
* @Date 2019/8/18 12:17
* @Version 1.0
**/
@Configuration
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
@Override
protected void configure(HttpSecurity http) throws Exception {
http.authorizeRequests().anyRequest().permitAll()
.and().csrf().disable();
}}

在主类上添加@EnableZuulProxy ，当然也需要注册到注册中心：

package com.eelve.lovin;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;
/**
* @ClassName LovinEurekaClientApplication
* @Description TDO
* @Author zhao.zhilue
* @Date 2019/8/15 16:37
* @Version 1.0
**/
@EnableZuulProxy
@EnableEurekaClient
@SpringBootApplication
public class LovinCloudZuulApplication {
public static void main(String[] args) {
SpringApplication.run(LovinCloudZuulApplication.class,args);
}}

这里为了方便测试，这里配置相应的过滤规则：

package com.eelve.lovin.filter;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.stereotype.Component;
import javax.servlet.http.HttpServletRequest;
/**
* @ClassName MyFilter
* @Description TDO
* @Author zhao.zhilue
* @Date 2019/8/18 12:44
* @Version 1.0
**/
@Component
@RefreshScope // 使用该注解的类，会在接到SpringCloud配置中心配置刷新的时候，自动将新的配置更新到该类对应的字段中。
@Slf4j
public class MyFilter extends ZuulFilter {
@Override
public String filterType() {
return "pre";
}
@Override
public int filterOrder() {
return 0;
}
@Override
public boolean shouldFilter() {
return true;
}
@Override
public Object run() throws ZuulException {
RequestContext ctx = RequestContext.getCurrentContext();
HttpServletRequest request = ctx.getRequest();
log.info(String.format("%s >>> %s", request.getMethod(), request.getRequestURL().toString()));
Object accessToken = request.getParameter("token");
if(accessToken == null) {
log.warn("token is empty");
ctx.setSendZuulResponse(false);
ctx.setResponseStatusCode(401);
try {
ctx.getResponse().getWriter().write("token is empty");
}catch (Exception e){}
return null;
}else if(!accessToken.equals("lovin")){
log.warn("token is not correct");
ctx.setSendZuulResponse(false);
ctx.setResponseStatusCode(403);
try {
ctx.getResponse().getWriter().write("token is not correct");
}catch (Exception e){}
return null;
}
log.info("ok");
return null;
}}

filterType：返回一个字符串代表过滤器的类型，在zuul中定义了四种不同生命周期的过滤器类型，具体如下： pre：路由之前 routing：路由之时 post：路由之后 error：发送错误调用 filterOrder：过滤的顺序 shouldFilter：这里可以写逻辑判断，是否要过滤，本文true,永远过滤。

run：过滤器的具体逻辑。可用很复杂，包括查sql，nosql去判断该请求到底有没有权限访问。