w.Header().Set(xhttp.LastModified, oi.ModTime.UTC().Format(http.TimeFormat))
	}

	if oi.ETag != "" {
		w.Header()[xhttp.ETag] = []string{"\"" + oi.ETag + "\""}
	}

	if oi.Expires != "" {
		w.Header().Set(xhttp.Expires, oi.Expires)
	}

	if oi.CacheControl != "" {
		w.Header().Set(xhttp.CacheControl, oi.CacheControl)
	}

	statusCode()
}

			},
			region:   region,
			expected: ErrUnsignedHeaders,
		},
		// (4) Should give an expired request if it has expired.
		{
			queryParams: map[string]string{
				"X-Amz-Algorithm":      signV4Algorithm,
				"X-Amz-Date":           now.AddDate(0, 0, -2).Format(iso8601Format),
				"X-Amz-Expires":        "60",
				"X-Amz-Signature":      "badsignature",

		canonicalHeaders += "\n"
	}

	date := expires // Date is set to expires date for presign operations.
	if date == "" {
		// If expires date is empty then request header Date is used.
		date = headers.Get(xhttp.Date)
	}

	// From the Amazon docs:
	//
	// StringToSign = HTTP-Verb + "\n" +
	// 	 Content-Md5 + "\n" +
	//	 Content-Type + "\n" +
	//	 Date/Expires + "\n" +
	//	 CanonicalizedProtocolHeaders +

	Inlined bool

	DataBlocks   int
	ParityBlocks int
}

// ExpiresStr returns a stringified version of Expires header in http.TimeFormat
func (o ObjectInfo) ExpiresStr() string {
	var expires string
	if !o.Expires.IsZero() {
		expires = o.Expires.UTC().Format(http.TimeFormat)
	}
	return expires
}

// ArchiveInfo returns any saved zip archive meta information.
// It will be decrypted if needed.

	}

	// Save expires in native time.Duration.
	preSignV4Values.Expires, e = time.ParseDuration(query.Get(xhttp.AmzExpires) + "s")
	if e != nil {
		return psv, ErrMalformedExpires
	}

	if preSignV4Values.Expires < 0 {
		return psv, ErrNegativeExpires
	}

	// Check if Expiry time is less than 7 days (value in seconds).
	if preSignV4Values.Expires.Seconds() > 604800 {

		},
		// (3) Should give an expired request if it has expired.
		{
			queryParams: map[string]string{
				"Expires":        "60",
				"Signature":      "badsignature",
				"AWSAccessKeyId": accessKey,
			},
			expected: ErrExpiredPresignRequest,
		},
		// (4) Should error when the signature does not match.
		{
			queryParams: map[string]string{
				"Expires":        fmt.Sprintf("%d", now.Unix()+60),

		err := spt.Refresh()
		if err != nil {
			return 0
		}
		// set the new token value
		tc.SetToken(spt.Token().AccessToken)

		// get the next token before the current one expires
		nextRenewal := float64(time.Until(spt.Token().Expires())) * 0.8
		if nextRenewal <= 0 {
			nextRenewal = float64(time.Second)
		}

		return time.Duration(nextRenewal)
	})

	return tc, nil
}

	d := UTCNow()
	// Find epoch expires when the request will expire.
	epochExpires := d.Unix() + expires

	// Add expires header if not present.
	expiresStr := req.Header.Get("Expires")
	if expiresStr == "" {
		expiresStr = strconv.FormatInt(epochExpires, 10)
		req.Header.Set("Expires", expiresStr)
	}

		ongoing: false,
		expiry:  expiry.UTC(),
	}
}

// String returns x-amz-restore compatible representation of r.
func (r restoreObjStatus) String() string {
	if r.Ongoing() {
		return `ongoing-request="true"`
	}
	return fmt.Sprintf(`ongoing-request="false", expiry-date="%s"`, r.expiry.Format(http.TimeFormat))
}

// Expiry returns expiry of restored object and true if restore-object has completed.

		NumVersions:      fi.NumVersions,
		SuccessorModTime: fi.SuccessorModTime,
		CacheControl:     fi.Metadata["cache-control"],
	}

	if exp, ok := fi.Metadata["expires"]; ok {
		if t, err := amztime.ParseHeader(exp); err == nil {
			objInfo.Expires = t.UTC()
		}
	}

	// Extract etag from metadata.
	objInfo.ETag = extractETag(fi.Metadata)

	// Add user tags to the object info