标签: caffeine-cache

是否可以将咖啡因CacheLoader::loadAll与@Cacheable带有集合参数的带注释方法一起使用，例如

@Cacheable(cacheNames = "exampleCache", cacheManager="exampleCacheManager", keyGenerator = "complexKeyGenerator")
   List<String> getItems(List<String> keys, String commonForEveryKey) {
      return ...
}

@Component
class ComplexKeyGenerator implements KeyGenerator {

      @Override
      public Object generate(Object target, Method method, Object... params) {
         return ((List<String>)params[0]).stream()
                     .map(item -> new ComplexKey(item, (String) params[1]))
                     .collect(Collectors.toList());
      }
}

@Data
   @AllArgsConstructor
   class ComplexKey {
      String key;
      String commonGuy;
}

class CustomCacheLoader implements CacheLoader<ComplexKey, String> {

      @Override
      public @Nullable String load(@NonNull ComplexKey key) throws Exception {
         return loadAll(List.of(key)).get(key);
      }

      @Override
      public @NonNull …

如何解决Spring Cloud LoadBalancer is currently working with the default cache. You can switch to using Caffeine cache, by adding it to the classpath.spring boot中的警告？

我正在尝试将咖啡因缓存集成到 kotlin+spring boot 应用程序中，但是，我遇到了在非协程主体中调用暂停函数的问题。我明白了，但我正在寻找一个应该更标准的解决方案。我在网上只能找到一个导致 SO 的解决方案，但我并没有真正找到解决此问题的稳定方法。

inMemoryCache.get(id) { id ->
   some call to external service <--- "Suspension function can be called only within coroutine body"
}

我正在使用 Caffeine 缓存来存储从外部系统接收到的数据。

LoadingCache<String, String> clientCache = Caffeine.newBuilder().expireAfterWrite(1, TimeUnit.MINUTES).build(id -> {
  System.out.println("Generating new value for " + id);
  if (id.equalsIgnoreCase("1")) {
    return null;
  }
  return new Date().toString();
});

System.out.println(clientCache.get("1"));
System.out.println(clientCache.get("1"));
System.out.println(clientCache.get("2"));
System.out.println(clientCache.get("3"));

这导致，

Generating new value for 1
null
Generating new value for 1
null
Generating new value for 2
Wed May 20 17:11:01 IST 2020
Generating new value for 3
Wed May 20 17:11:01 IST 2020
Wed May 20 17:11:01 IST 2020

咖啡因不会在缓存中保存空值。如何在咖啡因中存储空值？

我试图在 micronaut 中定义咖啡因缓存，并通过应用程序 yaml 设置过期时间。

文档表明​

micronaut.caches.discovery-client.expire-after-write应该被定义为一个Duration对象，但不清楚如何在 YAML 中这样做。

---
micronaut:
  application:
    name: example-service
  caches:
    example-cache:
      expire-after-write: 86400

给出以下错误：

Internal Server Error: Failed to inject value for parameter [expireAfterWrite] of method [setExpireAfterWrite] of class: io.micronaut.cache.caffeine.DefaultCacheConfiguration

Message: Error resolving property value [micronaut.caches.example-cache.expire-after-write]. Property doesn't exist
Path Taken: new $ExampleControllerDefinition$Intercepted(BeanContext beanContext,Qualifier qualifier,[Interceptor[] interceptors]) --> new CacheInterceptor([CacheManager cacheManager],CacheErrorHandler errorHandler,AsyncCacheErrorHandler asyncCacheErrorHandler,ExecutorService ioExecutor,BeanContext beanContext) --> new DefaultCacheManager([List caches],Provider dynamicCacheManager) --> new DefaultSyncCache([CacheConfiguration cacheConfiguration],ApplicationContext applicationContext,ConversionService conversionService) --> DefaultCacheConfiguration.setExpireAfterWrite([Duration expireAfterWrite])
io.micronaut.http.client.exceptions.HttpClientResponseException: Internal Server …

我有一个 Spring Cloud 网关，它将 API 剩余请求转发到一些微服务。

我想缓存特定请求的响应。为此我写了这个过滤器

@Component
@Slf4j
public class CacheResponseGatewayFilterFactory extends AbstractGatewayFilterFactory<CacheResponseGatewayFilterFactory.Config> {
   private final CacheManager cacheManager;

   public CacheResponseGatewayFilterFactory(CacheManager cacheManager) {
     super(CacheResponseGatewayFilterFactory.Config.class);
     this.cacheManager = cacheManager;
   }

   @Override
   public GatewayFilter apply(CacheResponseGatewayFilterFactory.Config config) {
     final var cache = cacheManager.getCache("MyCache");
     return (exchange, chain) -> {
        final var path = exchange.getRequest().getPath();
        if (nonNull(cache.get(path))) {
            log.info("Return cached response for request: {}", path);
            final var response = cache.get(path, ServerHttpResponse.class);
            final var mutatedExchange = exchange.mutate().response(response).build();
            return mutatedExchange.getResponse().setComplete();
        }

        return chain.filter(exchange).doOnSuccess(aVoid -> {
            cache.put(path, exchange.getResponse());
        }); …

我正在为 Spring Cache 使用 Caffeine Cache 库。有没有办法获取所有缓存的密钥？

我当前的应用程序处理近实时数据，流程如下：

在Cache Updater Thread（以固定时间间隔运行，与用户请求无关）中，我需要获取当前缓存中的所有键，从 Db 获取它们的最新数据，然后用于@CachePut更新缓存。

我在以下配置中使用咖啡因：

    Cache<String, String> cache = Caffeine.newBuilder()
                .executor(newWorkStealingPool(15))
                .scheduler(createScheduler())
                .expireAfterWrite(10, TimeUnit.SECONDS)
                .maximumSize(MAXIMUM_CACHE_SIZE)
                .removalListener(this::onRemoval)
                .build();


    private Scheduler createScheduler() {
        return forScheduledExecutorService(newSingleThreadScheduledExecutor());
    }

我是否正确地假设该onRemoval方法将在 ForkJoinPool 上执行newWorkStealingPool(15)，并且只会调用调度程序来查找需要驱逐的过期条目？

这意味着它会像这样：

1. 调用单线程调度程序（每约 1 秒）
2. 找到所有要驱逐的过期条目
3. newWorkStealingPool(15)对缓存构建器中的定义中的每个被逐出的条目执行 onRemoval 吗？

我没有找到解释此行为的文档，所以我在这里询问

总氮

我想将我的Caffeine缓存配置为在加载程序无法刷新缓存时返回过时的结果。以下 Kotlin 代码演示了这种情况：

    @Test
    fun `completeble future`() = runBlocking {
        val cache = Caffeine.newBuilder()
            .refreshAfterWrite(Duration.ofSeconds(1))
            .expireAfterWrite(Duration.ofSeconds(1))
            .buildAsync<String, String> { key: String, executor ->
                GlobalScope.future(executor.asCoroutineDispatcher()) {
                    throw Exception("== Error ==")
                }
            }

        cache.put("id", CompletableFuture.completedFuture("value"))

        delay(2000)

        assertEquals("value", cache.get("id").await())
    }

我希望这个测试能够通过，但我收到以下错误：

WARNING: Exception thrown during asynchronous load
java.lang.Exception: == Error ==
    at fsra.manager.TranslationManagerImplTest$completeble future$1$cache$1$1.invokeSuspend(TranslationManagerImplTest.kt:93)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.DispatchedTask.run(Dispatched.kt:241)
    at java.base/java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1426)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
    at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:177)




java.lang.Exception: == Error ==

    at fsra.manager.TranslationManagerImplTest$completeble future$1$cache$1$1.invokeSuspend(TranslationManagerImplTest.kt:93)
    at |b|b|b(Coroutine boundary.|b(|b)
    at …