Spring Cloud Alibaba学习06Gateway基本使用

Spring Cloud Gateway是基于Spring5、SpringBoot2.0和Project Reactor等技术开发的网关，目的是为微服务架构系统提供高性能，且简单易用的api路由管理方式。

优点：

1.性能强劲，是第一代网关Zuul的1.6倍。

2.功能强大，内置很多使用功能，例如：路由、过滤、限流、监控等。

3.易于扩展。

代码示例：

1、使用IDEA新建模块cloud-gw

pom文件添加如下引用：

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>cloud-demo01</artifactId>
        <groupId>org.yas</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <artifactId>cloud-gw</artifactId>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>
        <!-- 端点监控场景依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!-- nacos场景依赖 -->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
    </dependencies>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
</project>

2、application.yml配置文件：

server:
  port: 8040
spring:
  application:
    name: cloud-gateway

  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848
    gateway:
      routes:
        - id: cloud-goods
          # uri: http://localhost:9901/
          uri: lb://cloud-goods/ #使用Ribbon调用服务
          predicates: #谓词,断言
            - Path=/goods/**
            # - After=2021-11-11T16:02:30.200+08:00[Asia/Shanghai]
            # - Before=2022-11-11T16:02:30.200+08:00[Asia/Shanghai]
            # - Cookie=age,18
            # - Header=token,123
            # - Host=localhost,192.168.0.*,127.0.0.1
            # - Method=GET
          filters: #过滤器
            - AddRequestHeader=tonken,123
        - id: baidu #路由表，从上到下，按顺序匹配
          uri: http://www.baidu.com
          predicates:
            - Path=/**

3、启动类：

package com.yas;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@SpringBootApplication
@EnableDiscoveryClient//开启服务注册与发现功能
public class GWApp {
    public static void main(String[] args) {
        SpringApplication.run(GWApp.class,args);
    }
}

测试：

使用postman请求地址：localhost:8040/goods/findById/1

即可转发到cloud-goods服务对应的方法。

补充：跨域访问，添加如下配置类

package com.yas.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.reactive.CorsWebFilter;
import org.springframework.web.cors.reactive.UrlBasedCorsConfigurationSource;
import org.springframework.web.util.pattern.PathPatternParser;

@Configuration
public class CorsConfig {

    //解决跨域问题
    @Bean
    public CorsWebFilter corsFilter(){
        CorsConfiguration config = new CorsConfiguration();
        config.addAllowedHeader("*");
        config.addAllowedMethod("*");
        config.addAllowedOrigin("*");

        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource(new PathPatternParser());
        source.registerCorsConfiguration("/**",config);
        return new CorsWebFilter(source);
    }
}