SpringCloud实战之路 | 应用篇(六)网关组件Gateway及其过滤器
- 网关应用
- Gateway工作流程
- 代码实现
- GateWay过滤器
- GlobalFilter
- GateWayFilter
网关应用
Gateway工作流程
Spring Cloud Gateway是基于Reactor模型异步非阻塞的。
客户端向Spring Cloud Gateway发送请求。如果在Gateway Handler Mapping中找到与请求匹配的路由,则将其发送到Gateway Web Handler。Handler通过指定的过滤器链来将请求发送到我们实际的服务执行业务逻辑。然后返回。过滤器之间用虚线分库是因为过滤器可能会在发送代理请求前(pre)或后(post)执行业务逻辑。
- Filter在pre时: 可以做参数校验、权限校验、限流、日志输出等
- Filter在post时: 可以做响应内容、响应头的修改、日志输出、溜了监控等
代码实现
构建Gateway服务搭建
引入maven依赖
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>cloud-gateway-server</artifactId>
<!--spring boot 父启动器依赖-->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.6.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-commons</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<!--GateWay 网关-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<!--引入webflux-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<!--日志依赖-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</dependency>
<!--测试依赖-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!--lombok工具-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.4</version>
<scope>provided</scope>
</dependency>
<!--引入Jaxb,开始-->
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-core</artifactId>
<version>2.2.11</version>
</dependency>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-impl</artifactId>
<version>2.2.11</version>
</dependency>
<dependency>
<groupId>org.glassfish.jaxb</groupId>
<artifactId>jaxb-runtime</artifactId>
<version>2.2.10-b140310.1920</version>
</dependency>
<dependency>
<groupId>javax.activation</groupId>
<artifactId>activation</artifactId>
<version>1.1.1</version>
</dependency>
<!--引入Jaxb,结束-->
<!-- Actuator可以帮助你监控和管理Spring Boot应用-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<!--热部署-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
<!--Config 客户端依赖-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-config-client</artifactId>
</dependency>
<!--链路追踪-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>
</dependencies>
<dependencyManagement>
<!--spring cloud依赖版本管理-->
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Greenwich.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<!--编译插件-->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>11</source>
<target>11</target>
<encoding>utf-8</encoding>
</configuration>
</plugin>
<!--打包插件-->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
创建入口启动类
package com.cloud;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
@SpringBootApplication
@EnableDiscoveryClient
public class GateWayApplication {
public static void main(String[] args) {
SpringApplication.run(GateWayApplication.class,args);
}
}
创建配置文件yml
server:
port: 9002
eureka:
client:
serviceUrl: # eureka server的路径
defaultZone: http://LagouEurekaServerA:8761/eureka,http://LagouEurekaServerB:8762/eureka
instance:
prefer-ip-address: true
instance-id: ${spring.cloud.client.ip-address}:${spring.application.name}:${server.port}:@project.version@
spring:
application:
name: cloud-gateway-server
cloud:
gateway:
routes: # 路由可以有多个
- id: service-code-router
uri: lb://cloud-service-code
predicates:
- Path=/api/code/**
filters:
- StripPrefix=1
- id: service-email-router
uri: lb://cloud-service-email
predicates:
- Path=/api/email/**
filters:
- StripPrefix=1
- id: service-user-router #自定义的路由id 要保证唯一
uri: lb://cloud-service-user #lb表示从注册中心获取的需要转发的服务名称
#路由的规则
#例如访问localhost:9002/api/user/login,这里会路由到localhost:8080/user/login/
predicates:
- Path=/api/user/**
filters: # 可以去掉api之后转发
- StripPrefix=1
GateWay过滤器
Spring Cloud Gateway过滤器分为两种GlobalFilter(应用到全部路由)和GateWayFilter(应用到单个路由)
GlobalFilter
基于自定义过滤器实现全局的黑白名单
@Slf4j
@Component // 让容器扫描到,等同于注册了
public class BlackListFilter implements GlobalFilter, Ordered {
// 模拟⿊名单(实际可以去数据库或者redis中查询)
private static List<String> blackList = new ArrayList<>();
static {
blackList.add("0:0:0:0:0:0:0:1"); // 模拟本机地址
}
/**
* 过滤器核⼼⽅法
* @param exchange 封装了request和response对象的上下⽂
* @param chain ⽹关过滤器链(包含全局过滤器和单路由过滤器)
* @return
*/
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
// 思路:获取客户端ip,判断是否在⿊名单中,在的话就拒绝访问,不在的话就放⾏
// 从上下⽂中取出request和response对象
ServerHttpRequest request = exchange.getRequest();
ServerHttpResponse response = exchange.getResponse();
// 从request对象中获取客户端ip
String clientIp = request.getRemoteAddress().getHostString();
// 拿着clientIp去⿊名单中查询,存在的话就决绝访问
if(blackList.contains(clientIp)) {
// 决绝访问,返回
response.setStatusCode(HttpStatus.UNAUTHORIZED); // 状态码
log.debug("=====>IP:" + clientIp + " 在⿊名单中,将被拒绝访问!");
String data = "Request be denied!";
DataBuffer wrap = response.bufferFactory().wrap(data.getBytes());
return response.writeWith(Mono.just(wrap));
}
// 合法请求,放⾏,执⾏后续的过滤器
return chain.filter(exchange);
}
/**
* 返回值表示当前过滤器的顺序(优先级),数值越⼩,优先级越⾼
*/
@Override
public int getOrder() {
return 0;
}
}
GateWayFilter
针对某一个路由实现token信息验证
@Slf4j
public class TokenFilter implements GatewayFilter, Ordered {
/**
* 过滤器核心方法
* @param exchange 封装了request和response对象的上下文
* @param chain 网关过滤器链(包含全局过滤器和单路由过滤器)
* @return
*/
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
ServerHttpRequest request = exchange.getRequest();
ServerHttpResponse response = exchange.getResponse();
List<HttpCookie> cookieList = request.getCookies().get("token");
if (cookieList != null && cookieList.size() >0) {
return chain.filter(exchange);
}
response.setStatusCode(HttpStatus.UNAUTHORIZED);
String data = "token fail!!!";
DataBuffer wrap = response.bufferFactory().wrap(data.getBytes());
return response.writeWith(Mono.just(wrap));
}
/**
* 返回值表示当前过滤器的顺序(优先级),数值越小,优先级越高
* @return
*/
@Override
public int getOrder() {
return 0;
}
}
@Configuration
public class RouteLocatorConfig {
@Bean
public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
return builder
.routes()
.route(r -> r.path("/api/user/info/**")
.filters(f -> f.stripPrefix(1).filter(new TokenFilter()))
.uri("lb://cloud-service-user")
.order(0)
.id("service-user-router"))
.build();
}
}