使用springcloud的gateway作为网关

1.访问官网学习gateway 找到稳定版

2、官网介绍

2.1.5.RELEASE

This project provides an API Gateway built on top of the Spring Ecosystem, including: Spring 5, Spring Boot 2 and Project Reactor. Spring Cloud Gateway aims to provide a simple, yet effective way to route to APIs and provide cross cutting concerns to them such as: security, monitoring/metrics, and resiliency.

Glossary

Route（规则）: Route the basic building block of the gateway. It is defined by an ID, a destination URI, a collection of predicates and a collection of filters. A route is matched if aggregate predicate is true.
Predicate（断言）: This is a Java 8 Function Predicate. The input type is a Spring Framework ServerWebExchange. This allows developers to match on anything from the HTTP request, such as headers or parameters.
Filter: （过滤器）These are instances Spring Framework GatewayFilter constructed in with a specific factory. Here, requests and responses can be modified before or after sending the downstream request.

特点

Spring Cloud Gateway features:

Built on Spring Framework 5, Project Reactor and Spring Boot 2.0
是基于spring5，能够无缝整合springboot2.0
Able to match routes on any request attribute.
可以匹配任意请求属性
Predicates and filters are specific to routes.
断言和过滤器在特定的规则上
Hystrix Circuit Breaker integration.
整合熔断器
Spring Cloud DiscoveryClient integration
与Spring Cloud DiscoveryClient集成
Easy to write Predicates and Filters
简单编写的断言和过滤器
Request Rate Limiting
访问控制
Path Rewriting
路径重写

3.创建一个新maven的项目，来作为整个项目的网关 gulimall-gateway

4.修改pom文件

<?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>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>gulimall-gateway</artifactId>
    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-gateway</artifactId>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

5.开启服务注册发现

package com.lcl.gilimail.gateway;

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


//开启服务的注册和发现功能
@EnableDiscoveryClient
@SpringBootApplication
public class GuliMailGateWayApplication {

    public static void main(String[] args) {
        SpringApplication.run(GuliMailGateWayApplication.class,args);
    }
}

6.修改application.properties 配置nacos的地址

spring.application.name=gulimall-gateway
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848
server.port=88

7.启动nacos，在nacos中添加一个网关工程的namespace

8. 修改bootstrap.properties配置中心中的地址

spring.cloud.nacos.config.server-addr=localhost:8848
spring.cloud.nacos.config.namespace=d3495d51-d78f-4d76-8821-5c6a3b427510

9.在nacos配置中心中创建配置文件

10.（示例代码）在application.yml中新建路由规则

spring:
  cloud:
    gateway:
      routes:
      - id: test_route
        uri: https://www.baidu.com
        predicates:
        - Query=url,baidu

      - id: qq_routes
        uri: https://www.qq.com
        predicates:
        - Query=url,qq

11.启动测试

localhost:88?url=qq

网关统一配置

3.1在网关项目中创建网关配置类CorsConfiguration

package com.lcl.gilimall.gateway.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;

@Configuration
public class GuliMallCorsConfiguration {

    @Bean
    public CorsWebFilter corsWebFilter(){
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();

        CorsConfiguration corsConfiguration = new CorsConfiguration();
        //1.配置跨域
        corsConfiguration.addAllowedHeader("*");
        corsConfiguration.addAllowedMethod("*");
        corsConfiguration.addAllowedOrigin("*");
        //cookie信息
        corsConfiguration.setAllowCredentials(true);
        source.registerCorsConfiguration("/**",corsConfiguration);
        return new CorsWebFilter(source);
    }
}