}

// Set of s3 handler options as bit flags.
type s3HFlag uint8

const (
	// when provided, disables Gzip compression.
	noGZS3HFlag = 1 << iota

	// when provided, enables only tracing of headers. Otherwise, both headers
	// and body are traced.
	traceHdrsS3HFlag

	// when provided, disables throttling via the `maxClients` middleware.
	noThrottleS3HFlag
)

func (h s3HFlag) has(flag s3HFlag) bool {

func (r *CondCheck) Init(bucket, object string, header http.Header) {
	r.Key = object
	r.Bucket = bucket

	ifModifiedSinceHeader := header.Get(xhttp.IfModifiedSince)
	if ifModifiedSinceHeader != "" {
		if givenTime, err := amztime.ParseHeader(ifModifiedSinceHeader); err == nil {
			r.IfModifiedSince = &givenTime
		}
	}
	ifUnmodifiedSinceHeader := header.Get(xhttp.IfUnmodifiedSince)
	if ifUnmodifiedSinceHeader != "" {

)

// writeSTSErrorResponse writes error headers
func writeSTSErrorResponse(ctx context.Context, w http.ResponseWriter, errCode STSErrorCode, err error) {
	stsErr := stsErrCodes.ToSTSErr(errCode)

	// Generate error response.
	stsErrorResponse := STSErrorResponse{}
	stsErrorResponse.Error.Code = stsErr.Code
	stsErrorResponse.RequestID = w.Header().Get(xhttp.AmzRequestID)

			withJSON: `{"request":{"uri":"/1","header":{"User-Agent":"test"}}}
{"request":{"uri":"/2","header":{}}}`,
		},
		{
			name:  "is-not-missing-2",
			query: `select * from s3object[*] as s where s.request.header is not missing`,
			wantResult: `{"request":{"uri":"/1","header":{"User-Agent":"test"}}}
{"request":{"uri":"/2","header":{}}}`,
			withJSON: `{"request":{"uri":"/1","header":{"User-Agent":"test"}}}

### Transition Status

## Server-Side Encryption

MinIO supports two different types of server-side encryption ([SSE](#sse)):

- **SSE-C**: The MinIO server en/decrypts an object with a secret key provided by the S3 client as part of the HTTP request headers. Therefore, [SSE-C](#ssec) requires TLS/HTTPS.
- **SSE-S3**: The MinIO server en/decrypts an object with a secret key managed by a KMS. Therefore, MinIO requires a valid KMS configuration for [SSE-S3](#sses3).

	tr.ResponseHeaderTimeout = 30 * time.Minute

	return func() *http.Transport {
		return tr
	}
}

// NewHTTPTransportWithTimeout allows setting a timeout for response headers
func (s ConnSettings) NewHTTPTransportWithTimeout(timeout time.Duration) *http.Transport {
	tr := s.getDefaultTransport(0)

	// Settings specific to this transport.
	tr.ResponseHeaderTimeout = timeout
	return tr

	}, ErrNone
}

// Represents the overall state that is required for decoding a
// AWS Signature V4 chunked reader.
type s3ChunkedReader struct {
	reader        *bufio.Reader
	cred          auth.Credentials
	seedSignature string
	seedDate      time.Time
	region        string
	trailers      http.Header

	chunkSHA256Writer hash.Hash // Calculates sha256 of chunk data.
	buffer            []byte
	offset            int

}()

// Set of handler options as bit flags
type hFlag uint8

const (
	// this flag disables gzip compression of responses
	noGZFlag = 1 << iota

	// this flag enables tracing body and headers instead of just headers
	traceAllFlag

	// pass this flag to skip checking if object layer is available
	noObjLayerFlag
)

// Has checks if the given flag is enabled in `h`.
func (h hFlag) Has(flag hFlag) bool {

	UserTags string

	// List of individual parts, maximum size of upto 10,000
	Parts []ObjectPartInfo `json:"-"`

	// Implements writer and reader used by CopyObject API
	Writer       io.WriteCloser `json:"-" msg:"-"`
	Reader       *hash.Reader   `json:"-" msg:"-"`
	PutObjReader *PutObjReader  `json:"-" msg:"-"`

	metadataOnly bool
	versionOnly  bool // adds a new version, only used by CopyObject