SpringCloud 教程3 - Ribbon

之前把 employee-producer 加入了注册中心，下面把 employee-consumer 也加入注册中心，然后使用 ribbon 调用 employee-producer。

添加依赖，pom.xml

<?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>

    <groupId>com.example</groupId>
    <artifactId>employee-consumer</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>employee-consumer</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.17.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Edgware.SR4</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-ribbon</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>
        
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.6</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.9.6</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.9.6</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>

Ribbon配置类 RibbonConfiguration.java

public class RibbonConfiguration {
    @Autowired
    IClientConfig config;
    
    @Bean
    public IPing ribbonPing(IClientConfig config) {
        return new PingUrl();
    }
 
    @Bean
    public IRule ribbonRule(IClientConfig config) {
        return new AvailabilityFilteringRule();
    }
}

修改 ConsumerControllerClient.java 的调用方式：

public class ConsumerControllerClient {
    @Autowired
    private RestTemplate restTemplate;
    
    public void getEmployee() throws RestClientException, IOException {
        String res = restTemplate.getForObject("http://employee-producer/employee", String.class);
        System.out.println(res);
    }

    private static HttpEntity<?> getHeaders() throws IOException {
        HttpHeaders headers = new HttpHeaders();
        headers.set("Accept", MediaType.APPLICATION_JSON_VALUE);
        return new HttpEntity<>(headers);
    }
}

修改启动类，开启 eureka client 和 ribbon client

@SpringBootApplication
@EnableEurekaClient
@RibbonClient(name = "employee-client", configuration = RibbonConfiguration.class)
public class EmployeeConsumerApplication {

    public static void main(String[] args) throws RestClientException, IOException{
        ApplicationContext ctx = SpringApplication.run(EmployeeConsumerApplication.class, args);
        
        ConsumerControllerClient consumerControllerClient=ctx.getBean(ConsumerControllerClient.class);
        System.out.println(consumerControllerClient);
        consumerControllerClient.getEmployee();
    }
    
    @Bean
    @LoadBalanced
    public RestTemplate proviceRestTemplate() {
        return new RestTemplate();
    }
    
    @Bean
    public  ConsumerControllerClient  consumerControllerClient()
    {
        return  new ConsumerControllerClient();
    }
}

application.properties

spring.application.name=employee-consumer
server.port=8091
eureka.client.serviceUrl.defaultZone=http://localhost:8761/eureka/

启动 mvn spring-boot:run，可以看到输出：

2018-10-18 16:25:15.677  INFO 1258 --- [           main] c.n.l.DynamicServerListLoadBalancer      : DynamicServerListLoadBalancer for client employee-producer initialized: DynamicServerListLoadBalancer:{NFLoadBalancer:name=employee-producer,current list of Servers=[192.168.3.15:8070],Load balancer stats=Zone stats: {defaultzone=[Zone:defaultzone;    Instance count:1;   Active connections count: 0;Circuit breaker tripped count: 0;   Active connections per server: 0.0;]
},Server stats: [[Server:192.168.3.15:8070; Zone:defaultZone;   Total Requests:0;   Successive connection failure:0;    Total blackout seconds:0;   Last connection made:Thu Jan 01 08:00:00 CST 1970;  First connection made: Thu Jan 01 08:00:00 CST 1970;    Active Connections:0;   total failure count in last (1000) msecs:0; average resp time:0.0;  90 percentile resp time:0.0;    95 percentile resp time:0.0;    min resp time:0.0;  max resp time:0.0;  stddev resp time:0.0]
]}ServerList:org.springframework.cloud.netflix.ribbon.eureka.DomainExtractingServerList@3e0c7770
{"empId":"1","name":"emp1","designation":"manager","salary":3000.0}

成功调用了 employee-producer 拿到数据。