Predicate的使用

左手的ㄟ右手 2023-10-05 12:11 2阅读 0赞

#### Predicate的使用 ####

*   *  常用的Route Predicate

每次启动9527的时候都能看到  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center]

--------------------

**什么是Route Predicate Factories呢？**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center 1]

### 常用的Route Predicate ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center 2]  
**这里只挑几个来介绍由于太多 所以介绍所有的断言**  
1.After Route Predicate：必须要在这个时间之后才能路由

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center 3]

那么如何获得该格式的时间呢？

public class zone {
        
        public static void main(String[] args) {
        
            ZonedDateTime zonedDateTime = ZonedDateTime.now();
            System.out.println(zonedDateTime);
        }
    }

所有的断言演示

server:
      port: 9527
    spring:
      application:
        name: cloud-gateway
      cloud:
        gateway:
          discovery:
            locator:
              enabled: true  #开启从注册中心动态创建路由的功能，利用微服务名进行路由
          routes:
            - id: payment_routh #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
              predicates:
                - Path=/payment/get/**   #断言,路径相匹配的进行路由
     
            - id: payment_routh2
              #uri: http://localhost:8001   #匹配后提供服务的路由地址
              uri: lb://cloud-payment-service
              predicates:
                - Path=/payment/lb/**   #断言,路径相匹配的进行路由
                #- After=2020-03-08T10:59:34.102+08:00[Asia/Shanghai]
                #- Cookie=username,zhangshuai #并且Cookie是username=zhangshuai才能访问
                #- Header=X-Request-Id, \d+ #请求头中要有X-Request-Id属性并且值为整数的正则表达式
                #- Host=**.atguigu.com
                #- Method=GET
                #- Query=username, \d+ #要有参数名称并且是正整数才能路由
     
     
    eureka:
      instance:
        hostname: cloud-gateway-service
      client:
        service-url:
          register-with-eureka: true
          fetch-registry: true
          defaultZone: http://eureka7001.com:7001/eureka

**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**

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center]: https://img-blog.csdnimg.cn/20201022103017711.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center 1]: https://img-blog.csdnimg.cn/20201022103046486.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center 2]: https://img-blog.csdnimg.cn/20201022103123889.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5_size_16_color_FFFFFF_t_70_pic_center 3]: https://img-blog.csdnimg.cn/20201022103301979.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzIxMDQwNTU5,size_16,color_FFFFFF,t_70#pic_center