Spring Cloud重量路线谓词工厂

Weight Route Predicate Factory接受两个参数group和weight（一个int）。权重是按组计算的。

application.yml。 

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

此路由会将约80％的流量转发到https://weighthigh.org，并将约20％的流量转发到https://weighlow.org