@Test
  fun postInvalidatesCache() {
    testMethodInvalidates("POST")
  }

  @Test
  fun putInvalidatesCache() {
    testMethodInvalidates("PUT")
  }

  @Test
  fun deleteMethodInvalidatesCache() {
    testMethodInvalidates("DELETE")
  }

  private fun testMethodInvalidates(requestMethod: String) {
    // 1. Seed the cache.
    // 2. Invalidate it.