/**
     * Sets the authenticator used to respond to challenges from origin servers. Use
     * [proxyAuthenticator] to set the authenticator for proxy servers.
     *
     * If unset, the [no authentication will be attempted][Authenticator.NONE].
     */
    fun authenticator(authenticator: Authenticator) =
      apply {
        this.authenticator = authenticator
      }

## Version 3.4.2

_2016-11-03_

 *  Fix: Recover gracefully when an HTTP/2 connection is shutdown. We had a
    bug where shutdown HTTP/2 connections were considered usable. This caused
    infinite loops when calls attempted to recover.


## Version 3.4.1

_2016-07-10_

 *  **Fix a major bug in encoding HTTP headers.** In 3.4.0 and 3.4.0-RC1 OkHttp
    had an off-by-one bug in our HPACK encoder. This bug could have caused the

		// to attempt a heal on the object.
		if countErrs(errs, errDiskNotFound) > 0 {
			return
		}

		var missingBlocks int
		for i := range errs {
			if IsErr(errs[i],
				errFileNotFound,
				errFileVersionNotFound,
				errFileCorrupt,
			) {
				missingBlocks++
			}
		}

		// if missing metadata can be reconstructed, attempt to reconstruct.

	})

	// initialize the object layer.
	defer setObjectLayer(z)

	r := rand.New(rand.NewSource(time.Now().UnixNano()))
	attempt := 1
	for {
		var err error
		bootstrapTrace(fmt.Sprintf("poolMeta.Init: loading pool metadata, attempt: %d", attempt), func() {
			err = z.Init(ctx) // Initializes all pools.
		})
		if err != nil {
			if !configRetriableErrors(err) {

    resolve_symlinks: (Bool) Translate symbolic links into the real filepath.
    n_ask_attempts: (Integer) Number of times to query for valid input before
      raising an error and quitting.

  Returns:
    [String] The value of var_name after querying for input.

  Raises:
    UserInputError: if a query has been attempted n_ask_attempts times without
      success, assume that the user has made a scripting error, and will

	}
	return time.Unix(0, x.versions[0].header.ModTime)
}

func (x *xlMetaV2) addVersion(ver xlMetaV2Version) error {
	modTime := ver.getModTime().UnixNano()
	if !ver.Valid() {
		return errors.New("attempted to add invalid version")
	}
	encoded, err := ver.MarshalMsg(nil)
	if err != nil {
		return err
	}

	// returns error if we have exceeded configured object max versions

   *
   * <p>The returned {@code Future} attempts to keep its cancellation state in sync with that of the
   * input future and that of the future returned by the chain function. That is, if the returned
   * {@code Future} is cancelled, it will attempt to cancel the other two, and if either of the
   * other two is cancelled, the returned {@code Future} will receive a callback in which it will
   * attempt to cancel itself.
   *

	}

	wk, err := workers.New(workerSize)
	if err != nil {
		// invalid worker size.
		return err
	}

	retryAttempts := ri.RetryAttempts
	retry := false
	for attempts := 1; attempts <= retryAttempts; attempts++ {
		attempts := attempts
		// one of source/target is s3, skip delete marker and all versions under the same object name.

	if err := store.saveUserIdentity(ctx, cred.AccessKey, userType, ui); err != nil {
		return err
	}

	return cache.updateUserWithClaims(cred.AccessKey, ui)
}

// LoadUser - attempts to load user info from storage and updates cache.
func (store *IAMStoreSys) LoadUser(ctx context.Context, accessKey string) {
	cache := store.lock()
	defer store.unlock()

	cache.updatedAt = time.Now()

		}
		// if its a partial rename() do not attempt to delete recursively.
		// this can be healed since all parts are available.
		s.deleteFile(dstVolumeDir, dstDataPath, false, false)
		return res, osErrToFileErr(err)
	}

	if srcVolume != minioMetaMultipartBucket {
		// srcFilePath is some-times minioMetaTmpBucket, an attempt to
		// remove the temporary folder is enough since at this point