GetWay

SpringCloud - Spring Cloud 之 Gateway网关，Route路由，Predicate 谓词/断言，Filter 过滤器（十三）_spring.cloud.gateway.routes-CSDN博客

官网：Spring Cloud Gateway

工作原理：Spring Cloud Gateway

Glossary

Route: The basic building block of the gateway. It is defined by an ID, a destination URI, a collection of predicates, and a collection of filters. A route is matched if the aggregate predicate is true.
Predicate: This is a Java 8 Function Predicate. The input type is a Spring FrameworkServerWebExchange. This lets you match on anything from the HTTP request, such as headers or parameters.
Filter: These are instances of GatewayFilter that have been constructed with a specific factory. Here, you can modify requests and responses before or after sending the downstream request.

一、Route：路由

1）、正常路由

1、引入依赖

<!--引入nacos discovery-->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>

2、修改配置文件：如果spring.cloud.gateway.discovery.locator.enabled设置true，Gateway启动时将注册中心查询到的所有服务，自动创建默认路由规则：服务名/path

spring:
  application:
    name: gateway
  cloud:
    nacos:
      server-addr: localhost:8848
    gateway:
      routes:
        - id: user
          uri: http://localhost:8083
          predicates:
            - Path=/user/**
          filters:
            - StripPrefix=1
      discovery:
        locator:
          enabled: true #设置ture默认设置上面的route

2）、添加loadbalancer负载

1、添加依赖

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-loadbalancer</artifactId>
</dependency>

2、修改配置文件

spring:
  application:
    name: gateway
  cloud:
    nacos:
      server-addr: localhost:8848
    gateway:
      routes:
        - id: user
          uri: lb://user #loadbalancer负载修改
          predicates:
            - Path=/user/**
          filters:
            - StripPrefix=1
      discovery:
        locator:
          enabled: true

3）、整合nacos实现动态路由

1、nacos service配置创建gateway.yaml文件，保存gateway路由信息

2、引入配置

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-bootstrap</artifactId>
</dependency>

3、增加bootstrap.yaml配置

spring:
  cloud:
    nacos:
      # nacos作为配置中心的地址
      server-addr: localhost:8848
      config:
        file-extension: yaml
        shared-configs[0]:   # gateway.yaml
          data-id: gateway.yaml
          refresh: true

4、修改nacos service配置创建gateway.yaml文件，动态改变路由

5、原理：nacos修改配置文件->push客户端->nacos客户端调用NacosContextRefresher#registerNacosListener->发布RefreshEvent事件

->RefreshEventListener监听器->this#refresh#refresh() ->this#scoper#refreshAll()->发布RefreshScopeRefreshEvent事件：this#context#publishEvent(new RefreshScopeRefreshedEvent()) -> RouteRefreshListener监听器调用reset方法，发布RefreshRouteEnver事件

->CachingRouteLocator#onApplicationEvent完成路由规则的更新

简易版：nocos修改配置文件 -> push客户端 -> 客户端发布RefreshEvent事件、RefreshScopeRefreshEvent事件、RefreshRouteEnver事件 ->CachingRouteLocator完成本地缓存更新

3）、设置日志级别

logging:
  level:
    reactor.netty: debug

4）、设置actuator api：Spring Cloud Gateway

1、引入依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

2、修改配置文件

management:
  endpoints:
    web:
      exposure:
        include: '*'
  endpoint:
    health:
      show-details: always

3、常见api操作： Spring Cloud Gateway

4、访问： http://localhost:8090/actuator/gateway/routes

二、Predicate：断言：

1、Predicate与Filter两种配置方式： Spring Cloud Gateway

1)、快捷配置：Shortcut configuration

spring:
  cloud:
    gateway:
      routes:
      - id: after_route
        uri: https://example.org
        predicates:
        - Cookie=mycookie,mycookievalue

1)、完整扩展参数：Fully Expanded Arguments

spring:
  cloud:
    gateway:
      routes:
      - id: after_route
        uri: https://example.org
        predicates:
        - name: Cookie
          args:
            name: mycookie
            regexp: mycookievalue

2、路由断言工厂

1）、The After Route Predicate Factory：在指定事件之后的请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: after_route
        uri: https://example.org
        predicates:
        - After=2017-01-20T17:42:47.789-07:00[America/Denver]

2）、The Before Route Predicate Factory：在指定事件之前的请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: before_route
        uri: https://example.org
        predicates:
        - Before=2017-01-20T17:42:47.789-07:00[America/Denver]

3）、The Between Route Predicate Factory：在指定事件之间的请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: between_route
        uri: https://example.org
        predicates:
        - Between=2024-05-15T13:42:47.789-07:00[Asia/Shanghai], 2024-05-15T14:42:47.789-07:00[Asia/Shanghai]

4）、The Cookie Route Predicate Factory：带有指定Cookie名的请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: cookie_route
        uri: https://example.org
        predicates:
        - Cookie=chocolate, ch.p

5）、The Header Route Predicate Factory：带有指定请求头的请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: header_route
        uri: https://example.org
        predicates:
        - Header=X-Request-Id, \d+

6）、The Host Route Predicate Factory：带有指定host的请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: host_route
        uri: https://example.org
        predicates:
        - Host=**.somehost.org,**.anotherhost.org

7）、The Method Route Predicate Factory：指定方法请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: method_route
        uri: https://example.org
        predicates:
        - Method=GET,POST

8）、The Path Route Predicate Factory：指定请求路径请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: path_route
        uri: https://example.org
        predicates:
        - Path=/red/{segment},/blue/{segment}

9）、The Query Route Predicate Factory：指定查询参数请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: query_route
        uri: https://example.org
        predicates:
        - Query=green

10）、The RemoteAddr Route Predicate Factory：指定远程调用ip请求匹配

spring:
  cloud:
    gateway:
      routes:
      - id: remoteaddr_route
        uri: https://example.org
        predicates:
        - RemoteAddr=192.168.1.1/24 #24 是子网掩码

11）、The Weight Route Predicate Factory：指定远程调用ip请求匹配：使用权重来路由相应请求，以下代码表示有80%的请求会被路由到weighthigh.org、20%会被路由到weightlow.org

spring:
  cloud:
    gateway:
      routes:
      - id: weight_high
        uri: https://weighthigh.org
        predicates:
        - Weight=group1, 8
      - id: weight_low
        uri: https://weightlow.org
        predicates:
        - Weight=group1, 2

12）、The XForwarded Remote Addr Route Predicate Factory：指定请求X-Forwarded-For请求头匹配

spring:
  cloud:
    gateway:
      routes:
      - id: xforwarded_remoteaddr_route
        uri: https://example.org
        predicates:
        - XForwardedRemoteAddr=192.168.1.1/24

13）、自定义断言

1、创建时间配置

@Data
public class JackTimeBetweenConfig {
    private LocalTime begin;
    private LocalTime end;
}

2、创建断言工厂

@Component
public class SkTimeBetweenRoutePredicateFactory extends AbstractRoutePredicateFactory<SkTimeBetweenConfig> {
    public SkTimeBetweenRoutePredicateFactory() {
        super(SkTimeBetweenConfig.class);
    }

    // 定义配置配与配置文件中的配置项的映射关系
    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("begin", "end");
    }

    @Override
    public Predicate<ServerWebExchange> apply(SkTimeBetweenConfig config) {
        // 获取配置文件中的配置值
        LocalTime begin = config.getBegin();
        LocalTime end = config.getEnd();


        // full
        return new Predicate<ServerWebExchange>() {
            @Override
            public boolean test(ServerWebExchange serverWebExchange) {
                LocalTime now = LocalTime.now();
                return now.isAfter(begin) && now.isBefore(end);
            }
        };
    }
}

3、配置

spring:
  cloud:
    gateway:
      routes:
        - id: sktimebetween
          uri: lb://user    # 集成了loadbalancer   根据lb://   order名称进行服务发现和负载均衡得到一个结果值   http://localhost:9091/2/3   /order/query
          predicates:    # &&
          - Path=/time/**    # localhost:8090/jack/order/query
          - SkTimeBetween=下午2:00,下午4:00
          filters:
            - StripPrefix=1

三、Filter:过滤器

1、局部过滤器

1）、AddRequestHeader GatewayFilter Factory：为请求添加请求头

2）、AddRequestParameter GatewayFilter Factory：为请求添加请求参数

3）、AddResponseHeader GatewayFilter Factory：为响应添加响应头

4）、RequestRateLimiter GatewayFilter Factory：请求限流

5）、StripPrefix GatewayFilter Factory：表示要从前截取的路径个数

6）、StripPrefix GatewayFilter Factory

....等等

1.1、自定义局部过滤器

1）、新增局部过滤器

@Slf4j
@Component
public class LogPrintGatewayFilterFactory extends AbstractNameValueGatewayFilterFactory {
    @Override
    public GatewayFilter apply(NameValueConfig config) {
        return ((exchange, chain) -> {
            // 打印日志
            log.info("打印日志...{},{}",config.getName(),config.getValue());
            ServerHttpRequest request = exchange.getRequest().mutate().build();
            return chain.filter(exchange.mutate().request(request).build());
        });
    }
}

2）、新增配置

  filters:
    - StripPrefix=1
    - LogPrint=sk,18

2、全局过滤器

2.1、自定义全局过滤器

1）、新增自定义全局过滤器

@Component
public class CheckHeaderTokenGlobalFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        String value = exchange.getRequest().getHeaders().getFirst("token");// 以token为key的值
        if("token令牌".equals(value)){
            return chain.filter(exchange);
        }
        exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED);
        return exchange.getResponse().setComplete();
    }

    // order值越小，执行的优先级就越高
    @Override
    public int getOrder() {
        return 0;
    }
}

2）、请求头token入参含有token令牌

五、与nginx网关差异

1、API 网关介绍

网关 = 路由转发 + 过滤器（geteway filler 和 global fillter）

角色：一个API架构，用来保护、增强、控制对于API服务的访问，用来管理权限、访问控制、流量限制等

2、nginx

一个高性能的http和反向代理web服务器

3、geteway

微服务网关，统一路由、统一鉴权，跨域，限流等功能，springcloud gateway基于webflux框架实现

4、区别