SpringCloud+Nacos+Gateway

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SpringBoot整合Gateway+Nacos

本篇文章只演示通过gateway网关服务访问其他服务，不对gateway的其他功能做演示

一. 环境准备

1. 版本环境

• Jdk: <java.version>1.8</java.version>
• SpringBoot: <version>2.4.2</version>
• SpringCloud: <spring.cloud.version>2020.0.1</spring.cloud.version>
• SpringCloudAlibaba: <spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version>

以下是项目中pom配置，可拿来直接使用

1. 独立订单/用户服务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 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>2.4.2</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.scg</groupId><artifactId>spring-cloud-order-center</artifactId><version>0.0.1-SNAPSHOT</version><name>spring-cloud-order-center</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version><spring.cloud.version>2020.0.1</spring.cloud.version><spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version></properties><dependencyManagement><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>${spring.cloud.version}</version><type>pom</type><scope>import</scope></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alibaba-dependencies</artifactId><version>${spring-cloud-alibaba.version}</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.24</version></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

2. 独立网关服务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 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>2.4.2</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.scg</groupId><artifactId>spring-cloud-nacos</artifactId><version>0.0.1-SNAPSHOT</version><name>spring-cloud-gateway</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version><spring.cloud.version>2020.0.1</spring.cloud.version><spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version></properties><dependencyManagement><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>${spring.cloud.version}</version><type>pom</type><scope>import</scope></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alibaba-dependencies</artifactId><version>${spring-cloud-alibaba.version}</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId></dependency><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-gateway</artifactId></dependency><!--得不加上这个配置，不然会报503--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-loadbalancer</artifactId></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build>
</project>

2. 服务环境

本节使用一个简单的案例来演示Spring Cloud Gateway的使用方法,首先我们准备三个SpringBoo应用：

• spring-cloud-user-center : 独立用户服务
• spring-cloud-order-center : 独立订单服务
• spring-cloud-gateway： 独立的网关服务

二. 实战

1.创建用户服务

1. 引入相关依赖

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

2. yml配置

server:port: 8085spring:application:name: spring-cloud-user-centercloud:nacos:discovery:server-addr: 127.0.0.1:8848ip: 127.0.0.1
management:endpoints:web:exposure:include: "*"

3. 编写测试类

/*** @author gf* @date 2023/2/14*/
@Slf4j
@RestController
public class UserController {@RequestMapping("/user")public String user(){log.info("hello Mr gateway,this is user server");return "hello Mr gateway,this is user server";}
}

由于我们要将服务注册倒注册中心，所以我们在以内nacos依赖后要在启动类上添加@EnableDiscoveryClient注解

@EnableDiscoveryClient
@SpringBootApplication
public class SpringCloudUserCenterApplication {public static void main(String[] args) {SpringApplication.run(SpringCloudUserCenterApplication.class, args);}}

2.创建订单服务

创建订单服务和创建用户服务的过程一直，我们可以在测试类上做些改变以区分后面的调用
订单服务测试类

@Slf4j
@RestController
public class OrderController {@RequestMapping("/order")public String getOrder(){log.info("hello Mr gateway,this is order server");return "hello Mr gateway,this is order server";}
}

3.创建网关服务

1. 引入相关依赖

<?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>2.4.2</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.scg</groupId><artifactId>spring-cloud-nacos</artifactId><version>0.0.1-SNAPSHOT</version><name>spring-cloud-gateway</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version><spring.cloud.version>2020.0.1</spring.cloud.version><spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version></properties><dependencyManagement><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>${spring.cloud.version}</version><type>pom</type><scope>import</scope></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alibaba-dependencies</artifactId><version>${spring-cloud-alibaba.version}</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId></dependency><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-gateway</artifactId></dependency><!--得不加上这个配置，不然会报503--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-loadbalancer</artifactId></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build>
</project>

2. 配置yml文件

server:port: 8082
spring:application:name: gateway_servercloud:nacos:discovery:server-addr: 127.0.0.1:8848gateway:discovery:locator:#开启从注册中心动态创建路由的功能，利用微服务名进行路由enabled: true#开启小写验证，默认feign根据服务名查找都是用的全大写lowerCaseServiceId: trueroutes:- id: spring-cloud-order-centeruri: lb://spring-cloud-order-center# 断言,路径相匹配的进行路由predicates:- Path=/order-center/**filters:- StripPrefix=1- id: spring-cloud-user-centeruri: lb://spring-cloud-user-center# 断言,路径相匹配的进行路由predicates:- Path=/user-center/**filters:- StripPrefix=1
management:endpoints:web:exposure:include: "*"`3. 启动类添加@EnableDiscoveryClient注解```java
@EnableDiscoveryClient
@SpringBootApplication
public class SpringCloudGatewayApplication {public static void main(String[] args) {SpringApplication.run(SpringCloudGatewayApplication.class, args);}}

4.测试

同时启动三台服务，我们可以看到这三者服役已经注册到了nacos注册中心中

按照我们的配置，访问http://localhost:8082/user-center/user会调用用户中心的的user接口，访问http://localhost:8082/order-center/order会调用订单中心的order接口，接下来我们测试一下

通过网关访用户服务

通过网关访订单服务

三. 避坑指南

问题1–503问题

解决办法：添加如下依赖

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

问题原因：
参考：gateway 503 问题

问题2–网关服务启动报错

***************************
APPLICATION FAILED TO START
***************************Description:Parameter 0 of method modifyRequestBodyGatewayFilterFactory in org.springframework.cloud.gateway.config.GatewayAutoConfiguration required a bean of type 'org.springframework.http.codec.ServerCodecConfigurer' that could not be found.Action:Consider defining a bean of type 'org.springframework.http.codec.ServerCodecConfigurer' in your configuration.Process finished with exit code 1

问题原因：

这是由于所依赖的模块中有 spring-boot-starter-web 的依赖，而 SpringCloudGateway 还不支持 spring-boot-starter-web

解决方案：

网关服务去掉spring-boot-starter-web依赖

  <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency>