GateWay使用

1. 添加依赖

	
        
            org.springframework.cloud
            spring-cloud-starter-gateway
        

2. 修改yml

server:
  port: 9527

spring:
  application:
    name: cloud-gateway
#############################新增网关配置###########################
  cloud:
    gateway:
      routes:
        - id: payment_routh #payment_route    #路由的ID，没有固定规则但要求唯一，建议配合服务名
          uri: http://localhost:8001          #匹配后提供服务的路由地址
          #uri: lb://cloud-payment-service #匹配后提供服务的路由地址
          predicates:
            - Path=/payment/get/**         # 断言，路径相匹配的进行路由

        - id: payment_routh2 #payment_route    #路由的ID，没有固定规则但要求唯一，建议配合服务名
          uri: http://localhost:8001          #匹配后提供服务的路由地址
          #uri: lb://cloud-payment-service #匹配后提供服务的路由地址
          predicates:
            - Path=/payment/lb/**         # 断言，路径相匹配的进行路由
####################################################################

eureka:
  instance:
    hostname: cloud-gateway-service
  client: #服务提供者provider注册进eureka服务列表内
    service-url:
      register-with-eureka: true
      fetch-registry: true
      defaultZone: http://eureka7001.com:7001/eureka

3. Gateway配置路由的两种方式

@Configuration
public class GateWayConfig
{
    @Bean
    public RouteLocator customRouteLocator(RouteLocatorBuilder routeLocatorBuilder)
    {
        RouteLocatorBuilder.Builder routes = routeLocatorBuilder.routes();

        routes.route("path_route_atguigu",
                r -> r.path("/guonei")
                        .uri("http://news.baidu.com/guonei")).build();

        return routes.build();
    }
}

GateWay常用的Predicate

官方文档
Spring Cloud Gateway将路由匹配作为Spring WebFlux HandlerMapping基础架构的一部分。

Spring Cloud Gateway包括许多内置的Route Predicate工厂。所有这些Predicate都与HTTP请求的不同属性匹配。多个RoutePredicate工厂可以进行组合。

Spring Cloud Gateway创建Route 对象时，使用RoutePredicateFactory 创建 Predicate对象，Predicate 对象可以赋值给Route。Spring Cloud Gateway包含许多内置的Route Predicate Factories。
所有这些谓词都匹配HTTP请求的不同属性。多种谓词工厂可以组合，并通过逻辑and

常用的Route Predicate Factory

1. The After Route Predicate Factory
2. The Before Route Predicate Factory
3. The Between Route Predicate Factory
4. The Cookie Route Predicate Factory
5. The Header Route Predicate Factory
6. The Host Route Predicate Factory
7. The Method Route Predicate Factory
8. The Path Route Predicate Factory
9. The Query Route Predicate Factory
10. The RemoteAddr Route Predicate Factory
11. The weight Route Predicate Factory

讨论几个Route Predicate Factory
The After Route Predicate Factory

spring:
  cloud:
    gateway:
      routes:
      - id: after_route
        uri: https://example.org
        predicates:
        # 这个时间后才能起效
        - After=2017-01-20T17:42:47.789-07:00[America/Denver]

可以通过下述方法获得上述格式的时间戳字符串

import java.time.ZonedDateTime;
public class T2
{
    public static void main(String[] args)
    {
        ZonedDateTime zbj = ZonedDateTime.now(); // 默认时区
        System.out.println(zbj);

       //2021-02-22T15:51:37.485+08:00[Asia/Shanghai]
    }
}

The Between Route Predicate Factory

spring:
  cloud:
    gateway:
      routes:
      - id: between_route
        uri: https://example.org
        # 两个时间点之间
        predicates:
        - Between=2017-01-20T17:42:47.789-07:00[America/Denver], 2017-01-21T17:42:47.789-07:00[America/Denver]

The Cookie Route Predicate Factory

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

The cookie route predicate factory takes two parameters, the cookie name and a regular expression.

This predicate matches cookies that have the given name and whose values match the regular expression.

测试

# 该命令相当于发get请求，且没带cookie
curl http://localhost:9527/payment/lb

# 带cookie的
curl http://localhost:9527/payment/lb --cookie "chocolate=chip"

The Header Route Predicate Factory

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

测试

# 带指定请求头的参数的CURL命令
curl http://localhost:9527/payment/lb -H "X-Request-Id:123"

小结
说白了，Predicate就是为了实现一组匹配规则，让请求过来找到对应的Route进行处理。