技術標籤：微服務

本篇配置類及其他程式碼可參考《Hystrix使用fallback完成消費降級》

我們在Hystrix下新建一個CacheService

@Slf4j
@Service
public class RequestCacheService {

    @Autowired
    private MyService service;

    @CacheResult
    @HystrixCommand(commandKey = "cacheKey")
    public Friend requestCache(@CacheKey String name)
 
 {
        log.info("request cache " + name);
        Friend friend = new Friend();
        friend.setName(name);
        friend = service.sayHiPost(friend);
        log.info("after requesting cache " + name);
        return friend;
    }
}

建立一個測試Controller，在這裡我們嘗試呼叫兩次requestCache()

@GetMapping("/cache")
publicFriend cache(String name) {
    @Cleanup HystrixRequestContext context = HystrixRequestContext.initializeContext();

    Friend friend = requestCacheService.requestCache(name);
    friend = requestCacheService.requestCache(name);
    return friend;
}

啟動專案，我們呼叫localhost:50000/cache?name=王老五

@GetMapping("/cache")
publicFriend cache(String name) {
    @Cleanup HystrixRequestContext context =  HystrixRequestContext.initializeContext();

    Friend friend = requestCacheService.requestCache(name);
    name += "!";
    friend = requestCacheService.requestCache(name);
    return friend;
}

重啟專案，再次請求，這時候能看到Feign中觸發了兩次呼叫

說明@CacheKey已經生效了，在傳入相同key時，觸發了Hystrix的快取!