Spring Cloud Alibaba

1、Nacos

版本说明 · alibaba/spring-cloud-alibaba Wiki (github.com)

什么是 Nacos

Nacos 支持 AP 和 CP 模式的切换

父 POM

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.3.2.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
    <java.version>1.8</java.version>
    <spring.cloud.version>Hoxton.SR9</spring.cloud.version>
    <spring.cloud.alibaba.version>2.2.6.RELEASE</spring.cloud.alibaba.version>
</properties>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
</dependencies>
<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>${spring.cloud.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-dependencies</artifactId>
            <version>${spring.cloud.alibaba.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

1.1 服务发现

1.1.1 服务提供者

• POM

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

• yaml

server:
  port: 8082
spring:
  application:
    name: nacos-provider
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
management:
  endpoints:
    web:
      exposure:
        exclude: '*'

• 启动类添加 @EnableDiscoveryClient
• Controller

@RestController
@RequestMapping("/test")
public class TestController {
    @Value("${server.port}")
    private String port;
    @GetMapping("/port")
    public Object getPort(){
        return port;
    }
}

1.1.2 消费者

• POM

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

• yaml

server:
  port: 8181
spring:
  application:
    name: nacos-consumer
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
server-url:
  # 服务提供者 spring.application.name
  nacos-provider: http://nacos-provider

• 启动类添加 @EnableDiscoveryClient
• 配置 RestTemplate

@Bean
@LoadBalanced
public RestTemplate restTemplate(){
    return new RestTemplate();
}

• Controller

@RestController
@RequestMapping("/consumer")
public class ConsumerController {
    @Autowired
    private RestTemplate restTemplate;
    @Value("${server-url.nacos-provider}")
    private String serverUrl;
    @GetMapping("/port")
    public Object getPort(){
        return restTemplate.getForObject(serverUrl+"/test/port",String.class);
    }
}

1.2 配置中心

• POM

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

• bootstrap.yml

server:
  port: 8081
spring:
  application:
    name: nacos-provider
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
      config:
        server-addr: 127.0.0.1:8848
        file-extension: yaml
management:
  endpoints:
    web:
      exposure:
        exclude: '*'

• application.yaml

spring:
  profiles:
    active: dev

• 启动类添加 @EnableDiscoveryClient
• Controller

@RestController
// 动态刷新
@RefreshScope
@RequestMapping("/test")
public class TestController {
    @Value("${config.info}")
    private String config;
    @GetMapping("/config")
    public Object getConfig(){
        return config;
    }
}

• 配置文件名称

{spring.profiles.active}.${file-extension}

• prefix 默认为 spring.application.name 的值，也可以通过配置项 spring.cloud.nacos.config.prefix来配置。
• spring.profiles.active 即为当前环境对应的 profile，详情可以参考 Spring Boot文档。 注意：当 **spring.profiles.active** 为空时，对应的连接符 **-** 也将不存在，dataId 的拼接格式变成 **${prefix}.${file-extension}**
• file-exetension 为配置内容的数据格式，可以通过配置项 spring.cloud.nacos.config.file-extension 来配置。目前只支持 properties 和 yaml 类型。

2、Sentinel

• POM

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba.csp</groupId>
    <artifactId>sentinel-datasource-nacos</artifactId>
</dependency>

• yaml

spring:
  application:
    name: sentinel-test
  cloud:
    sentinel:
      transport:
        dashboard: 127.0.0.1:8080