在 Kotlin 和 JUnit5 中测试 Spring Boot 缓存

Question

我有一个简单的存储库，它是用 Kotlin 编写的用于从 db 获取站点列表的界面；我用 Spring 缓存缓存响应：

interface IRepository {
  fun sites(): List<String>
}

@Repository
class Repository(private val jdbcTemplate: NamedParameterJdbcTemplate) : IRepository {
  private val sites = "SELECT DISTINCT siteId FROM sites"

  @Cacheable(value = ["sites"], key = "sites")
  override fun sites(): List<String> = jdbcTemplate.jdbcTemplate.queryForList(sites, String::class.java)
}

现在我想测试一下缓存是否真的有效。作为测试的基础，我使用了How to test Spring's declarative caching support on Spring Data repositories?，但直接实现导致存储库是代理而不是存储库的错误。所以我目前的尝试是：

@ContextConfiguration
@ExtendWith(SpringExtension::class)
class RepositoryCacheTests {
  @MockBean
  private lateinit var repository: Repository

  @Autowired
  private lateinit var cache: CacheManager

  @EnableCaching
  @TestConfiguration
  class CachingTestConfig {
    @Bean
    fun cacheManager(): CacheManager = ConcurrentMapCacheManager("sites")
  }

  @Test
  fun `Sites is cached after first read`() {
    // Arrange
    whenever(repository.sites()).thenReturn(listOf(site, anotherSite))

    repository.sites()

    // Assert
    assertThat(cache.getCache("sites")?.get("sites")).isNotNull
  }

但是缓存是空的并且在第一次读取后没有填充。我的设置中缺少什么？

更新：

根据 George 的建议，我更新了测试（以及更容易模拟的代码）。我还必须在配置中为存储库添加@Bean，因为没有Could not autowire. No beans of 'Repository' type found.。

  @Cacheable(value = ["sites"], key = "'sites'")
  override fun sites(): List<String> = jdbcTemplate.query(sites) { rs, _ -> rs.getString("siteId") }

@ContextConfiguration
@ExtendWith(SpringExtension::class)
class RepositoryCacheTests {
  @MockBean
  private lateinit var jdbcTemplate: NamedParameterJdbcTemplate

  @Autowired
  private lateinit var repository: Repository

  @Autowired
  private lateinit var cache: CacheManager

  @EnableCaching
  @TestConfiguration
  class CachingTestConfig {
    @Bean
    fun testRepository(jdbcTemplate: NamedParameterJdbcTemplate): Repository = Repository(jdbcTemplate)

    @Bean
    fun cacheManager(): CacheManager = ConcurrentMapCacheManager("sites")
  }

  @Test
  fun `Sites is cached after first read`() {
    whenever(jdbcTemplate.query(any(), any<RowMapper<String>>())).thenReturn(listOf(site, anotherSite))
    repository.sites()
    assertThat(cache.getCache("sites")?.get("sites")).isNotNull
    repository.sites()
    verify(jdbcTemplate, times(1)).query(any(), any<RowMapper<String>>())
  }
}

现在测试甚至还没有开始：

Error creating bean with name 'RepositoryCacheTests': Unsatisfied dependency expressed through field 'repository'; nested exception is org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'testRepository' is expected to be of type 'Repository' but was actually of type 'com.sun.proxy.$Proxy52'

更新 2：

正如乔治指出的那样，解决方案是（https://stackoverflow.com/a/44911329/492882 和 https://stackoverflow.com/a/44911329/492882）

  @Autowired
  private lateinit var repository: IRepository

Answer 1

你在嘲笑你的测试对象Repository repository。这应该是由 Spring 初始化的真实对象，因此它具有缓存。您需要模拟您的测试对象正在调用的JdbcTemplate。

我真的不知道 kotlin 语法，所以请耐心等待。您的测试应如下所示：

@ContextConfiguration
@ExtendWith(SpringExtension::class)
class RepositoryCacheTests {
  @MockBean
  private lateinit jdbcTemplate: NamedParameterJdbcTemplate
  @Autowired
  private lateinit var repository: IRepository

  @Autowired
  private lateinit var cache: CacheManager

  @EnableCaching
  @TestConfiguration
  class CachingTestConfig {
    @Bean
    fun cacheManager(): CacheManager = ConcurrentMapCacheManager("sites")
  }

  @Test
  fun `Sites is cached after first read`() {
    // Arrange
    whenever(jdbcTemplate.queryForList(any(), String::class.java)).thenReturn(listOf(site, anotherSite))

    repository.sites()

    // Assert
    assertThat(cache.getCache("sites")?.get("sites")).isNotNull

    //Execute again to test cache.
    repository.sites()
    //JdbcTemplate should have been called once.
    verify(jdbcTemplate, times(1)).queryForList(any(), String::class.java)
  }