- CallStart 
 - **CacheMiss**
 - ProxySelectStart
 - ... Standard Events ...
 - CallEnd
        
### Conditional Cache Hit
 
When cache flags require checking the cache results are still valid an early cacheConditionalHit event is
received followed by a cache hit or miss.  Critically in the cache hit scenario the server won’t send the response body.

      }

      fileToClose?.closeQuietly()
    }
  }

  companion object {
    // TODO(jwilson): what to do about timeouts? They could be different and unfortunately when any
    //     timeout is hit we like to tear down the whole stream.

    private const val SOURCE_UPSTREAM = 1
    private const val SOURCE_FILE = 2

    @JvmField val PREFIX_CLEAN = "OkHttp cache v1\n".encodeUtf8()

          i = end
        } while (i < newline)
        i++
      }
    }
  }

  private fun loggerTag(loggerName: String): String {
    // We need to handle long logger names before they hit Log.
    // java.lang.IllegalArgumentException: Log tag "okhttp3.mockwebserver.MockWebServer" exceeds limit of 23 characters
    return knownLoggers[loggerName] ?: loggerName.take(23)
  }

  fun enable() {

    mockWebServer.dispatcher = dispatcher
    val url = mockWebServer.url("/").toUrl()
    val conn = url.openConnection() as HttpURLConnection
    conn.responseCode // Force the connection to hit the "server".
    // Make sure our dispatcher got the request.
    assertThat(requestsMade.size).isEqualTo(1)
  }

  @Test
  fun outOfOrderResponses() {
    val firstResponseCode = AtomicInteger()

   * have reached a limit, this returns [END_OF_DATA].
   */
  internal fun readHeader(): DerHeader {
    require(peekedHeader == null)

    // We've hit a local limit.
    if (byteCount == limit) return END_OF_DATA

    // We've exhausted the source stream.
    if (limit == -1L && source.exhausted()) return END_OF_DATA

    // Read the tag.

 *    created.
 *  * **[Network Count:][networkCount]** the number of those requests that required network use.
 *  * **[Hit Count:][hitCount]** the number of those requests whose responses were served by the
 *    cache.
 *
 * Sometimes a request will result in a conditional cache hit. If the cache contains a stale copy of
 * the response, the client will issue a conditional `GET`. The server will then send either

            ~/.android/avd/*
            ~/.android/adb*
          key: avd-${{ matrix.api-level }}

      - name: Create AVD and generate snapshot for caching
        if: steps.avd-cache.outputs.cache-hit != 'true'
        uses: reactivecircus/android-emulator-runner@v2
        with:
          api-level: ${{ matrix.api-level }}
          arch: ${{ matrix.api-level == '34' && 'x86_64' || 'x86' }}

  }

  private fun testRequestMethod(
    requestMethod: String,
    expectCached: Boolean,
    withOverride: Boolean = false,
  ) {
    // 1. Seed the cache (potentially).
    // 2. Expect a cache hit or miss.
    server.enqueue(
      MockResponse.Builder()
        .addHeader("Expires: " + formatDate(1, TimeUnit.HOURS))
        .addHeader("X-Response-ID: 1")
        .build(),
    )
    server.enqueue(

    if (credential == response.request.header("Authorization")) {
      return null // If we already failed with these credentials, don't retry.
     }
    ```

    You may also skip the retry when you’ve hit an application-defined attempt limit:

    ```kotlin
    if (response.responseCount >= 3) {
      return null // If we've failed 3 times, give up.
    }
    ```

      .assertCode(200)
      .assertBody("A")
    val request1ReceivedAt = System.currentTimeMillis()
    assertThat(server.takeRequest().headers["If-None-Match"]).isNull()

    // Hit that stored response. It's different, but Vary says it doesn't matter.
    Thread.sleep(10) // Make sure the timestamps are unique.
    val cacheHit =
      executeSynchronously(
        "/",