gateway断言配置详解

一、Predicate - 断⾔

 1、简单用法

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

 2、自定义断言

新建类VipRoutePredicateFactory，注意VipRoutePredicateFactory名字的前缀和yml文件的配置必须一致，即yml文件必须配置为前缀Vip

import jakarta.validation.constraints.NotEmpty;
import org.springframework.cloud.gateway.handler.predicate.AbstractRoutePredicateFactory;
import org.springframework.cloud.gateway.handler.predicate.GatewayPredicate;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.server.ServerWebExchange;

import java.util.Arrays;
import java.util.List;
import java.util.function.Predicate;


@Component
public class VipRoutePredicateFactory extends AbstractRoutePredicateFactory<VipRoutePredicateFactory.Config> {


    public VipRoutePredicateFactory() {
        super(Config.class);
    }

    @Override
    public Predicate<ServerWebExchange> apply(Config config) {
        return new GatewayPredicate() {
            @Override
            public boolean test(ServerWebExchange serverWebExchange) {
                // localhost/search?q=haha&user=leifengyang
                ServerHttpRequest request = serverWebExchange.getRequest();

                String first = request.getQueryParams().getFirst(config.param);

                return StringUtils.hasText(first) && first.equals(config.value);
            }
        };
    }

    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("param", "value");
    }

    /**
     * 可以配置的参数
     */
    @Validated
    public static class Config {

        @NotEmpty
        private String param;


        @NotEmpty
        private String value;

        public @NotEmpty String getParam() {
            return param;
        }

        public void setParam(@NotEmpty String param) {
            this.param = param;
        }

        public @NotEmpty String getValue() {
            return value;
        }

        public void setValue(@NotEmpty String value) {
            this.value = value;
        }
    }
}

yml文件配置：

spring:
  cloud:
    gateway:
      routes:
      - id: after_route
        uri: https://example.org
        predicates:
        - After=2017-01-20T17:42:47.789-07:00[America/Denver]
        - Vip=user,wangcj  #表示传了参数user为wangcj的才满足要求