zuul网关

Posted 2021-03-23 ztbk

Zuul路由网关简介及基本使用

简介

Zuul API路由网关服务简介

 

请看上图，这里的API 路由网关服务 由Zuul实现，主要就是对外提供服务接口的时候，起到了请求的路由和过滤作用，也因此能够隐藏内部服务的接口细节，从来有利于保护系统的安全性；

路由配置

Zuul 路由配置

我们新建一个module  microservice-zuul-3001

这里我们的zuul也注册到eureka服务里，端口3001；

我们修改下Hosts，专门为zuul搞个本地域名映射 

hosts文件 加下：

127.0.0.1  zuul.jt.com

然后pom

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>com.jt</groupId>
        <artifactId>microservice</artifactId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <artifactId>modulemicroservice-zuul-3001</artifactId>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <!--zuul网关-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-zuul</artifactId>
        </dependency>
        <!-- actuator监控 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!-- hystrix容错 -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-hystrix</artifactId>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

搞一个 application.yml 

server:
  port: 3001
  context-path: /
spring:
  application:
    name: microservice-zuul
eureka:
  instance:
    instance-id: microservice-zuul:3001
    prefer-ip-address: true
  client:
    service-url:
      defaultZone: http://eureka2001.jt.com:2001/eureka/,http://eureka2002.jt.com:2002/eureka/,http://eureka2003.jt.com:2003/eureka/
info:
  groupId: com.jt.testSpringcloud
  artifactId: microservice-zuul-3001
  version: 1.0-SNAPSHOT
  userName: http://jt.com
  phone: 123456

建一个主启动类：ZuulApplication_3001

加下@EnableZuulProxy注解

package com.jt.modulemicroservicezuul3001;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;

@SpringBootApplication(exclude={DataSourceAutoConfiguration.class, HibernateJpaAutoConfiguration.class})
@EnableZuulProxy
public class ModulemicroserviceZuul3001Application {

    public static void main(String[] args) {
        SpringApplication.run(ModulemicroserviceZuul3001Application.class, args);
    }

}

 

再加入一个ZuulFallBack

package com.jt.modulemicroservicezuul3001.fallback;

import org.springframework.cloud.netflix.zuul.filters.route.ZuulFallbackProvider;
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;

@Component
public class ZuulFallBack implements ZuulFallbackProvider {

    @Override
    public String getRoute() {
        return "*";
    }

    /**
     * 在给zuul整合回退功能时，只要类实现ZuulFallbackProvider接口，并且注册bean即可。
     *
     * 不过需要注意的时，这个回退只有服务掉线或者超时的情况下才会触发（Camden.SR4版本测试是这样），
     * 如果服务程序出现异常，此回退程序是不能处理的，异常会直接返回给调用者，比如页面。
     *
     * @return
     */
    @Override
    public ClientHttpResponse fallbackResponse() {
        return new ClientHttpResponse() {
            @Override
            public HttpHeaders getHeaders() {
                HttpHeaders headers = new HttpHeaders();
                headers.setContentType(MediaType.APPLICATION_JSON_UTF8);//application/json;charset=UTF-8
                return headers;
            }

            @Override
            public InputStream getBody() throws IOException {
                String msg = "服务繁忙，请稍后.....";
                //new ByteArrayInputStream("{"code":-1,"msg":"服务暂不可用"}".getBytes(StandardCharsets.UTF_8))
                return new ByteArrayInputStream(msg.getBytes());
            }

            @Override
            public String getStatusText() throws IOException {
                return HttpStatus.BAD_REQUEST.getReasonPhrase();//400
            }

            @Override
            public HttpStatus getStatusCode() throws IOException {
                return HttpStatus.BAD_REQUEST;
            }

            @Override
            public int getRawStatusCode() throws IOException {
                return HttpStatus.BAD_REQUEST.value();//"Bad Request"
            }

            @Override
            public void close() {

            }
        };
    }
}

 

 

Zuul路由映射配置

上面是zuul的简单使用，从接口地址很轻易的就暴露了服务提供者的唯一标识名microservice-student；有安全风险，我们需要将其隐藏；

ignored-services的作用是将原来的服务提供者唯一标识名禁用；

Prefix的作用是给服务加前缀

yml文件中添加以下配置：

zuul:
  routes:
    studentServer.serviceId: microservice-student
    studentServer.path: /studentServer/**
  ignored-services: "*"
  prefix: /jt

Zuul请求过滤配置

比如我们登录某个系统 需要身份验证，用户名密码啥的；

 

我们请求服务，也可以来设置身份验证，也就是过滤非法请求；Zuul通过ZuulFilter过滤器实现；

一般具体实现的话 每次经过Zuul服务网关 我们都对带来的token进行有效性验证；

 

我们先定义一个 AccessFilter类：

 

package com.jt.modulemicroservicezuul3001.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.apache.log4j.Logger;

import javax.servlet.http.HttpServletRequest;


public class AccessFilter extends ZuulFilter {

    Logger logger=Logger.getLogger(AccessFilter.class);

    /**
     * 判断该过滤器是否要被执行
     */
    @Override
    public boolean shouldFilter() {
        return true;
    }

    /**
     * 过滤器的具体执行逻辑
     */
    @Override
    public Object run() throws ZuulException {
        RequestContext ctx = RequestContext.getCurrentContext();
        HttpServletRequest request = ctx.getRequest();
        String parameter = request.getParameter("accessToken");
        logger.info(request.getRequestURL().toString()+" 请求访问");
        if(parameter==null){
            logger.error("accessToken为空！");
            ctx.setSendZuulResponse(false);
            ctx.setResponseStatusCode(401);
            ctx.setResponseBody("{"result":"accessToken is empty!"}");
            return null;
        }
        //  token判断逻辑
        logger.info(request.getRequestURL().toString()+" 请求成功");
        return null;
    }

    /**
     * 过滤器的类型 这里用pre，代表会再请求被路由之前执行
     */
    @Override
    public String filterType() {
        return "pre";
    }

    /**
     * 过滤器的执行顺序
     */
    @Override
    public int filterOrder() {
        return 0;
    }

}

然后再开启下 Filter配置：

package com.jt.modulemicroservicezuul3001.config;

import com.jt.modulemicroservicezuul3001.filter.AccessFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ZuulConfig {

    @Bean
    public AccessFilter accessFilter(){
        return new AccessFilter();
    }
}