【雕爷学编程】Arduino动手做（200）---WS2812B幻彩LED灯带-CFANZ编程社区

内容简介

maven依赖

<dependencies>
    <dependency>
        <groupId>com.netflix.feigngroupId>
        <artifactId>feign-coreartifactId>
        <version>8.18.0version>
    dependency>
    <dependency>
        <groupId>com.netflix.feigngroupId>
        <artifactId>feign-jacksonartifactId>
        <version>8.18.0version>
    dependency>
    <dependency>
        <groupId>com.netflix.feigngroupId>
        <artifactId>feign-ribbonartifactId>
        <version>8.18.0version>
    dependency>
	<dependency>
    <groupId>com.netflix.archaiusgroupId>
    <artifactId>archaius-coreartifactId>
dependency>

dependencies>
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配置读取

import com.netflix.config.ConfigurationManager;
import feign.Feign;
import feign.jackson.JacksonDecoder;
import feign.jackson.JacksonEncoder;
import feign.ribbon.RibbonClient;
public class AppRun {
    public static void main(String[] args) throws Exception {
        User param = new User();
        param.setUsername("test");
        RemoteService service = Feign.builder().client(RibbonClient.create())
				.encoder(new JacksonEncoder())
                .decoder(new JacksonDecoder())
			    .options(new Options(1000, 3500))
                .retryer(new Retryer.Default(5000, 5000, 3))
			    .target(RemoteService.class, "http://remote-client/gradle-web");

        for (int i = 1; i 10; i++) {
            User result = service.getOwner(param);
            System.out.println(result.getId() + "," + result.getUsername());
        }
    }
}
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声明了一个User类型的对象param，该对象将作为参数被发送至服务生产端。
重点在于通过RibbonClient.create()使得Feign对象获得了Ribbon的特性。之后通过encoder,decoder设置编码器与解码器，并通过target方法将之前定义的接口RemoteService与一个URL地址http://remote-client/gradle-web进行了绑定。

remote-client.ribbon.MaxAutoRetries=1
remote-client.ribbon.MaxAutoRetriesNextServer=1
remote-client.ribbon.OkToRetryOnAllOperations=true
remote-client.ribbon.ServerListRefreshInterval=2000
remote-client.ribbon.ConnectTimeout=3000
remote-client.ribbon.ReadTimeout=3000
remote-client.ribbon.listOfServers=127.0.0.1:8080,127.0.0.1:8085
remote-client.ribbon.EnablePrimeConnections=false
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在调用时会被替换为：

@RequestLine指定的地址进行拼接，得到最终请求地址。本例中最终请求地址为：

由于使用的ribbon，所以feign不再需要配置超时时长，重试策略。ribbon提供了更为完善的策略实现。


public class UserController {

    public User list( User user) throws InterruptedException{
        HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest();
        user.setId(new Long(request.getLocalPort()));
        user.setUsername(user.getUsername().toUpperCase());
        return user;
    }
}

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首先利用archaius项目的com.netflix.config.ConfigurationManager读取配置文件remote-client.properties,该文件位于src/main/resources下。

import com.netflix.client.ClientFactory;
import com.netflix.client.config.IClientConfig;
import com.netflix.config.ConfigurationManager;
import com.netflix.loadbalancer.ILoadBalancer;
import com.netflix.loadbalancer.RandomRule;
import com.netflix.loadbalancer.ZoneAwareLoadBalancer;
import feign.Feign;
import feign.jackson.JacksonDecoder;
import feign.jackson.JacksonEncoder;
import feign.ribbon.LBClient;
import feign.ribbon.LBClientFactory;
import feign.ribbon.RibbonClient;
public class AppRun {
    public static void main(String[] args) throws Exception {
        ConfigurationManager.loadPropertiesFromResources("remote-client.properties");
        User param = new User();
        param.setUsername("test");
        RibbonClient client = RibbonClient.builder().lbClientFactory(new LBClientFactory() {

            public LBClient create(String clientName) {
                IClientConfig config = ClientFactory.getNamedConfig(clientName);
                ILoadBalancer lb = ClientFactory.getNamedLoadBalancer(clientName);
                ZoneAwareLoadBalancer zb = (ZoneAwareLoadBalancer) lb;
                zb.setRule(new RandomRule());
                return LBClient.create(lb, config);
            }
        }).build();
        RemoteService service = Feign.builder().client(client).encoder(new JacksonEncoder())
                .decoder(new JacksonDecoder()).options(new Options(1000, 3500))
                .retryer(new Retryer.Default(5000, 5000, 3)).target(RemoteService.class, "http://remote-client/gradle-web");

        for (int i = 1; i 10; i++) {
            User result = service.getOwner(param);
            System.out.println(result.getId() + "," + result.getUsername());
        }
    }
}
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	private IRule zoneAvoidanceRule() {
        return new ZoneAvoidanceRule();
    }

    private IRule randomRule() {
        return new RandomRule();
    }
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