1. pom包，主要是记录版本

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.17</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.student.gateway</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <url/>
    <licenses>
        <license/>
    </licenses>
    <developers>
        <developer/>
    </developers>
    <scm>
        <connection/>
        <developerConnection/>
        <tag/>
        <url/>
    </scm>
    <properties>
        <java.version>8</java.version>
    </properties>
    <dependencies>

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
            <version>2021.0.5.0</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-gateway -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
            <version>3.1.9</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
            <version>2021.0.5.0</version>
        </dependency>

        <!--sentinel gateway-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-sentinel-gateway</artifactId>
            <version>2021.0.5.0</version>
        </dependency>
        
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
            <version>2021.0.5.0</version>
        </dependency>

        <!-- 202.0.5版本的cloud，需要这个注解才能负载均衡也就是 lb:student才生效 -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-loadbalancer</artifactId>
            <version>3.1.4</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

2. Nacos搭建，我这边是2.x版本的

3. yaml配置

server:
  port: 8004

spring:
  application:
    name: gateway
  config:
    import: nacos:gateway.yaml  // config的全名
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
      config:
        server-addr: 127.0.0.1:8848
        file-extension: yaml
    sentinel:
      transport:
        dashboard: 127.0.0.1:8005
      eager: true
    gateway:
      routes:
        - id: student
          uri: lb://student
          predicates:
            - Path=/api/redis/**
          filters:
            - StripPrefix=1 // 过滤前缀
            - Log=23 // 自定义过滤器

4. 自定义过滤器写法

package com.student.gateway.demo.filters.gateway;

import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;
import java.util.Arrays;
import java.util.List;

@Component
public class LogGatewayFilterFactory extends AbstractGatewayFilterFactory<LogModal> {

    public LogGatewayFilterFactory() {
        super(LogModal.class);
    }

    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("name1");
    }

    @Override
    public GatewayFilter apply(LogModal config) {
        return new GatewayFilter() {
            @Override
            public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
                System.out.println(config.getName1());
                Mono<Void> mono = chain.filter(exchange);
                return mono;
            }
        };
    }
}

package com.student.gateway.demo.filters.gateway;

public class LogModal {

    private String name1;

    public String getName1() {
        return name1;
    }

    public void setName1(String name1) {
        this.name1 = name1;
    }

}

5. 全局过滤器

package com.student.gateway.demo.filters.gateway;

import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;
import java.util.Arrays;
import java.util.List;

@Component
public class LogGatewayFilterFactory extends AbstractGatewayFilterFactory<LogModal> {

    public LogGatewayFilterFactory() {
        super(LogModal.class);
    }

    @Override
    public List<String> shortcutFieldOrder() {
        return Arrays.asList("name1");
    }

    @Override
    public GatewayFilter apply(LogModal config) {
        return new GatewayFilter() {
            @Override
            public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
                System.out.println(config.getName1());
                Mono<Void> mono = chain.filter(exchange);
                return mono;
            }
        };
    }
}

6. sentinel的下载，限流和熔断