养蜂人 (Beekeeper)
养蜂人研究蜜蜂繁殖规律，计算每只蜜蜂 (雄蜂/雌蜂) 的祖先数量。因为蜜蜂繁殖规律和黄金分割数列相关，所以养蜂人同时消费技工提供的计算服务。
研究(http://www.dave-cushman.net/bee/fibonacci.html)表明，雄蜂(Drone)由未受精卵孵化而生，只有母亲；而雌蜂(Queen)由受精卵孵化而生，既有母又有父。
Credit: Dave Cushman’s website
参考上图，蜜蜂的某一代祖先数量符合黄金分割数列的模型，由此我们可以很快实现服务功能。
蜜蜂繁殖规律研究服务
首先我们定义黄金数列运算接口：
public interface FibonacciCalculator { long term(int n);}
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接下来定义并实现蜜蜂繁殖规律研究服务:
interface BeekeeperService { long ancestorsOfDroneAt(int generation);
long ancestorsOfQueenAt(int generation);}
class BeekeeperServiceImpl implements BeekeeperService {
private final FibonacciCalculator fibonacciCalculator;
BeekeeperServiceImpl(FibonacciCalculator fibonacciCalculator) { this.fibonacciCalculator = fibonacciCalculator; }
@Override public long ancestorsOfDroneAt(int generation) { if (generation <= 0) { return 0; } return fibonacciCalculator.term(generation + 1); }
@Override public long ancestorsOfQueenAt(int generation) { if (generation <= 0) { return 0; } return fibonacciCalculator.term(generation + 2); }}
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这里我们用到之前定义的 FibonacciCalculator 接口，并希望通过这个接口远程调用技工服务端点。@RpcReference 注释能帮助我们自动从 Service Center 中获取 microserviceName = “worker”, schemaId = “fibonacciRpcEndpoint” ， 即服务名为 worker 已经 schema ID 为 fibonacciRpcEndpoint 的端点：
@Configurationclass BeekeeperConfig {
@RpcReference(microserviceName = "worker", schemaId = "fibonacciRpcEndpoint") private FibonacciCalculator fibonacciCalculator;
@Bean BeekeeperService beekeeperService() { return new BeekeeperServiceImpl(fibonacciCalculator); }}
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我们在技工一节已定义好对应的服务名和 schema ID 端点，通过上面的配置，ServiceComb 会自动将远程技工服务 实例和 FibonacciCalculator 绑定在一起。
养蜂人服务端点
与上一节技工服务相似，我们在这里也需要提供养蜂人服务端点，让用户可以进行调用：
@RestSchema(schemaId = "beekeeperRestEndpoint")@RequestMapping("/rest")@Controllerpublic class BeekeeperController {
private static final Logger logger = LoggerFactory.getLogger(BeekeeperController.class);
private final BeekeeperService beekeeperService;
@Autowired BeekeeperController(BeekeeperService beekeeperService) { this.beekeeperService = beekeeperService; }
@RequestMapping(value = "/drone/ancestors/{generation}", method = GET, produces = APPLICATION_JSON_UTF8_VALUE) @ResponseBody public Ancestor ancestorsOfDrone(@PathVariable int generation) { logger.info( "Received request to find the number of ancestors of drone at generation {}", generation);
return new Ancestor(beekeeperService.ancestorsOfDroneAt(generation)); }
@RequestMapping(value = "/queen/ancestors/{generation}", method = GET, produces = APPLICATION_JSON_UTF8_VALUE) @ResponseBody public Ancestor ancestorsOfQueen(@PathVariable int generation) { logger.info( "Received request to find the number of ancestors of queen at generation {}", generation);
return new Ancestor(beekeeperService.ancestorsOfQueenAt(generation)); }}
class Ancestor { private long ancestors;
Ancestor() { }
Ancestor(long ancestors) { this.ancestors = ancestors; }
public long getAncestors() { return ancestors; }}
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因为养蜂人需要消费技工提供的服务，所以其 microservice.yaml 配置稍有不同：
# all interconnected microservices must belong to an application wth the same IDAPPLICATION_ID: companyservice_description:# name of the declaring microservice name: beekeeper version: 0.0.1cse: service: registry: address: http://sc.servicecomb.io:30100 rest: address: 0.0.0.0:8090 handler: chain: Consumer: default: bizkeeper-consumer,loadbalance references:# this one below must refer to the microservice name it communicates with worker: version-rule: 0.0.1
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这里我们需要定义 cse.references.worker.version-rule ，让配置名称中指向技工服务名 worker ，并匹配其版本号。
最后定义养蜂人服务应用入口：
@SpringBootApplication@EnableServiceCombpublic class BeekeeperApplication {
public static void main(String[] args) { SpringApplication.run(BeekeeperApplication.class, args); }}
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本文转载自微服务蜂巢公众号。
原文链接：https://mp.weixin.qq.com/s?__biz=MzUxNTEwNTg5Mg==&mid=2247488670&idx=1&sn=7556990599cea8e0fd80ed54b9f39026&chksm=f9bae195cecd688332940d0b296909e8130d828104c36c20f49d76d43561f626eae24bd0c1ef&scene=0&xtrack=1&key=17fbc717c1803f309d535a4bdbc0f9c0d8d2089a5c7e455df8c0a5e6d824a6534b8476d2ad151cd45ed10eb7a15577914596444e867d96f615c277fc05fe951cef48de8b7d0732dcb4bc74f5c0e2f95a&ascene=14&uin=MTI5MjAyNjcyMQ%3D%3D&devicetype=Windows+10&version=62070158&lang=zh_CN&exportkey=AfH3CzqE%2F1ENttvg815y9Uo%3D&pass_ticket=oGcazNeaRfkuszcDU0L7jpfeTFZ3%2FULBAbPnhurUkiyW7DLvBVsoC%2Fh5OWX1zIsH
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