播放2.4测试出错：CacheManager已关闭。它不能再使用了

Question

我们的应用程序基于Play 2.4、Scala 2.11和Akka。使用的数据库是MySQL。

缓存在我们的应用程序中被大量使用。我们使用Play的默认EhCache进行缓存。

我们的示例代码片段：

import play.api.Play.current
import play.api.cache.Cache

case class Sample(var id: Option[String],
                 //.. other fields
)

class SampleTable(tag: Tag)
  extends Table[Sample](tag, "SAMPLE") {
  def id = column[Option[String]]("id", O.PrimaryKey)
  // .. other field defs
}

object SampleDAO extends TableQuery(new SampleTable(_)) with SQLWrapper {
  def get(id: String) : Future[Sample] = {
    val cacheKey = // our code to generate a unique cache key
    Cache.getOrElse[Future[[Sample]](cacheKey) {
      db.run(this.filter(_.id === id).result.headOption)
    }
  }
}

我们使用Play的内置规范2进行测试。

var id = "6879a389-aa3c-4074-9929-cca324c7a01f"

  "Sample Application " should {
    "Get a Sample" in new WithApplication {
      val req = FakeRequest(GET, s"/v1/samples/$id")
      val result = route(req).get
      assertEquals(OK, status(result))
      id = (contentAsJson(result).\("id")).get.toString().replaceAllLiterally("\"", "")
   }

但是在单元测试中，我们经常会遇到以下错误。

[error]    1) Error in custom provider, java.lang.IllegalStateException: The  CacheManager has been shut down. It can no longer b
e used.
[error]      at play.api.cache.EhCacheModule.play$api$cache$EhCacheModule$$bindCache$1(Cache.scala:181):
[error]    Binding(interface net.sf.ehcache.Ehcache qualified with QualifierInstance(@play.cache.NamedCache(value=play)) to Prov
iderTarget(play.api.cache.NamedEhCacheProvider@7c8b0968)) (via modules: com.google.inject.util.Modules$OverrideModule -> play.ap
i.inject.guice.GuiceableModuleConversions$$anon$1)
[error]      while locating net.sf.ehcache.Ehcache annotated with @play.cache.NamedCache(value=play)
[error]      at play.api.cache.EhCacheModule.play$api$cache$EhCacheModule$$bindCache$1(Cache.scala:182):
[error]    Binding(interface play.api.cache.CacheApi qualified with QualifierInstance(@play.cache.NamedCache(value=play)) to Pro
viderTarget(play.api.cache.NamedCacheApiProvider@38514c74)) (via modules: com.google.inject.util.Modules$OverrideModule -> play.
api.inject.guice.GuiceableModuleConversions$$anon$1)
[error]      while locating play.api.cache.CacheApi annotated with @play.cache.NamedCache(value=play)
[error]      while locating play.api.cache.CacheApi
[error]
[error]    1 error (InjectorImpl.java:1025)
[error] com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1025)
[error] com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1051)
[error] play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:321)
[error] play.api.inject.guice.GuiceInjector.instanceOf(GuiceInjectorBuilder.scala:316)
[error] play.api.Application$$anonfun$instanceCache$1.apply(Application.scala:234)
[error] play.api.Application$$anonfun$instanceCache$1.apply(Application.scala:234)
[error] play.utils.InlineCache.fresh(InlineCache.scala:69)
[error] play.utils.InlineCache.apply(InlineCache.scala:62)
[error] play.api.cache.Cache$.cacheApi(Cache.scala:63)
[error] play.api.cache.Cache$.getOrElse(Cache.scala:106

我们期待在解决上述问题或实现专门用于测试的模拟缓存方面获得帮助。

提前谢谢。

Answer 1

我认为通过伪造缓存来绕过缓存测试是一种糟糕的做法。它使您的测试无效，这都是因为您试图不以可扩展和分布式的方式使用EhCache。更好的方法是实现@Singleton接口，如下所述：https://stackoverflow.com/a/31835029/5736587

多亏了https://stackoverflow.com/users/2145368/mon-calamari

Answer 2

另一种解决方案是在每次测试开始时调用顺序方法。

class MySpec extends Specification {
  sequential

  ...
}

笔记

parallelExecution in Test := false

也应该在build.sbt文件中设置。

Answer 3

我有一个类似的问题，所以我剔除了一个缓存实现并将其替换为测试。

class FakeCache extends CacheApi {
  override def set(key: String, value: Any, expiration: Duration): Unit = {}

  override def get[T](key: String)(implicit evidence$2: ClassManifest[T]): Option[T] = None

  override def getOrElse[A](key: String, expiration: Duration)(orElse: => A)(implicit evidence$1: ClassManifest[A]): A = orElse

  override def remove(key: String): Unit = {}
}

覆盖喷射：

class AbstractViewTest extends PlaySpecification {

  def testApp(handler: DeadboltHandler): Application = new GuiceApplicationBuilder()
                                                   .overrides(bind[CacheApi].to[FakeCache])
                                                   .in(Mode.Test)
                                                   .build()

}

你可以看到我如何在GitHub上使用它：https://github.com/schaloner/deadbolt-2-scala/blob/master/code/test/be/objectify/deadbolt/scala/views/AbstractViewTest.scala