index = opts.IndexCB()
	}

	actualSize := data.ActualSize()
	if actualSize < 0 {
		_, encrypted := crypto.IsEncrypted(fi.Metadata)
		compressed := fi.IsCompressed()
		switch {
		case compressed:
			// ... nothing changes for compressed stream.
			// if actualSize is -1 we have no known way to
			// determine what is the actualSize.
		case encrypted:
			decSize, err := sio.DecryptedSize(uint64(n))

Interceptors can be chained. Suppose you have both a compressing interceptor and a checksumming interceptor: you'll need to decide whether data is compressed and then checksummed, or checksummed and then compressed. OkHttp uses lists to track interceptors, and interceptors are called in order.

![Interceptors Diagram](../assets/images/******@****.***)

### Application Interceptors

    server.webSocket!!.send(message)
    taskFaker.runTasks()
    assertThat(client.clientSourceBufferSize())
      .isGreaterThan(message.length.toLong()) // Not compressed.
    assertThat(client.processNextFrame()).isTrue()
    client.listener.assertTextMessage(message)
  }

  @Test
  fun messagesCompressedWhenConfigured() {

#      batch: 100 # upto this many objects per archive
#      inmemory: true # indicates if the archive must be staged locally or in-memory
#      compress: false # S2/Snappy compressed archive
#      smallerThan: 5MiB # create archive for all objects smaller than 5MiB
#      skipErrs: false # skips any source side read() errors

  # target where the objects must be replicated
  target:

		return io.ErrUnexpectedEOF
	}
	ver := int(b[0])
	switch ver {
	case dataUsageCacheVerV1:
		return errors.New("cache version deprecated (will autoupdate)")
	case dataUsageCacheVerV2:
		// Zstd compressed.
		dec, err := zstd.NewReader(r, zstd.WithDecoderConcurrency(2))
		if err != nil {
			return err
		}
		defer dec.Close()

		dold := &dataUsageCacheV2{}

import okio.GzipSink
import okio.buffer

internal class GzipRequestBody(
  val delegate: RequestBody,
) : RequestBody() {
  override fun contentType() = delegate.contentType()

  // We don't know the compressed length in advance!
  override fun contentLength() = -1L

  override fun writeTo(sink: BufferedSink) {
    GzipSink(sink).buffer().use(delegate::writeTo)
  }

  override fun isOneShot() = delegate.isOneShot()

@SuppressWarnings("serial") // uses writeReplace(), not default serialization
final class SingletonImmutableSet<E> extends ImmutableSet<E> {
  // We deliberately avoid caching the asList and hashCode here, to ensure that with
  // compressed oops, a SingletonImmutableSet packs all the way down to the optimal 16 bytes.

  final transient E element;

  SingletonImmutableSet(E element) {
    this.element = Preconditions.checkNotNull(element);
  }

## Rewriting Responses

If transparent compression was used, OkHttp will drop the corresponding response headers `Content-Encoding` and `Content-Length` because they don’t apply to the decompressed response body.

If a conditional GET was successful, responses from the network and cache are merged as directed by the spec.

## Follow-up Requests

				},
			},
			result: false,
		},
	}
	for i, test := range testCases {
		t.Run(strconv.Itoa(i), func(t *testing.T) {
			got := test.objInfo.IsCompressed()
			if got != test.result {
				t.Errorf("IsCompressed: Expected %v but received %v",
					test.result, got)
			}
			got, gErr := test.objInfo.IsCompressedOK()
			if got != test.result {

	t.Run("default+versioned", func(t *testing.T) {
		fn(t, nil, MakeBucketOptions{VersioningEnabled: true})
	})

	t.Run("compressed", func(t *testing.T) {
		fn(t, func() {
			resetCompressEncryption()
			enableCompression(t, false, []string{"*"}, []string{"*"})
		}, MakeBucketOptions{})
	})
	t.Run("compressed+versioned", func(t *testing.T) {
		fn(t, func() {
			resetCompressEncryption()