SpringCloud使用Nacos服務發現實現遠端呼叫
關於Nacos之前寫了兩篇文章關於SpringBoot對它的使用,感興趣可以檢視一下。
在SpringBoot使用的時候,需要自行去向Nacos服務註冊自己的服務,Nacos也提供了SpringCloud服務發現的依賴,本文結合spring-cloud-starter-alibaba-nacos-discovery進行使用介紹。
本文使用版本為:
- SpringCloud Finchley.SR2
- SpringBoot 2.0.3.RELEASE
- spring-cloud-starter-alibaba-nacos-discovery 0.2.1.RELEASE
- spring-cloud-starter-openfeign 2.0.0.RELEASE
2.本文場景
兩個服務,如下:
- springcloud-nacos-discovery-provider:埠號10000,服務提供者。
- springcloud-nacos-discovery-consumer:埠號10001,服務消費者。
原理很簡單,瀏覽器訪問消費者,消費者呼叫服務提供者。
3.服務提供者
3.1 依賴配置
建立一個專案,專案中加入SpringCloud-Nacos依賴,完整pom如下所示。
<?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"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.dalaoyang</groupId> <artifactId>springcloud_nacos_discovery_provider</artifactId> <version>0.0.1-SNAPSHOT</version> <name>springcloud_nacos_discory_provider</name> <description>springcloud_nacos_discovery_provider</description> <properties> <java.version>1.8</java.version> <spring-cloud.version>Finchley.SR2</spring-cloud.version> </properties> <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.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId> <version>0.2.1.RELEASE</version> </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> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> 複製程式碼
3.2 啟動類
在啟動類加入@SpringBootApplication註解,完整啟動類程式碼如下所示。
package com.dalaoyang; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; @SpringBootApplication @EnableDiscoveryClient public class SpringcloudNacosDiscoveryProviderApplication { public static void main(String[] args) { SpringApplication.run(SpringcloudNacosDiscoveryProviderApplication.class, args); } } 複製程式碼
3.3 配置檔案
配置檔案中配置Nacos服務地址,當前服務名,這裡需要注意一點,使用Ribbon負載均衡的時候服務名中不能使用下劃線,不然會找不到服務。
配置檔案如下所示。
server.port=10000 spring.application.name=springcloud-nacos-discovery-provider spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848 複製程式碼
3.4 提供服務
建立一個Controller,提供一個方法進行測試,如下所示。
package com.dalaoyang.controller; import org.springframework.web.bind.annotation.*; /** * @author yangyang * @date 2019/2/4 */ @RestController public class TestController { @GetMapping("/test/{string}") public String test(@PathVariable String string) { return "Hello Nacos :" + string; } } 複製程式碼
4 服務消費者
4.1 依賴配置
與服務提供者類似,在服務消費者加入SpringCloud-Nacos依賴和OpenFeign依賴,完整pom入夏所示。
<?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"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.dalaoyang</groupId> <artifactId>springcloud_nacos_discovery_consumer</artifactId> <version>0.0.1-SNAPSHOT</version> <name>springcloud_nacos_discovery_consumer</name> <description>springcloud_nacos_discovery_consumer</description> <properties> <java.version>1.8</java.version> <spring-cloud.version>Finchley.SR2</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> <version>2.0.0.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId> <version>0.2.1.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </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> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> 複製程式碼
4.2 啟動類
在啟動類加入註解@EnableDiscoveryClient並且開啟負載均衡,如下所示。
package com.dalaoyang; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; import org.springframework.cloud.client.loadbalancer.LoadBalanced; import org.springframework.context.annotation.Bean; import org.springframework.web.client.RestTemplate; @SpringBootApplication @EnableDiscoveryClient public class SpringcloudNacosDiscoveryConsumerApplication { public static void main(String[] args) { SpringApplication.run(SpringcloudNacosDiscoveryConsumerApplication.class, args); } @LoadBalanced @Bean public RestTemplate restTemplate() { return new RestTemplate(); } } 複製程式碼
4.3 配置檔案
配置檔案與提供者一致,只是服務名不同,如下所示。
server.port=10001 spring.application.name=springcloud-nacos-discovery-consumer spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848 複製程式碼
4.4 建立服務呼叫
建立一個Controller進行呼叫服務,如下所示。
package com.dalaoyang.controller; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.client.RestTemplate; /** * @author yangyang * @date 2019/2/4 */ @RestController public class TestConrtroller { @Autowired private RestTemplate restTemplate; @GetMapping("test/{string}") public String test(@PathVariable String string) { return restTemplate.getForObject("http://springcloud-nacos-discovery-provider/test/" + string, String.class); } } 複製程式碼