type nsScannerOptions struct {
	DiskID   string          `msg:"id"`
	ScanMode int             `msg:"m"`
	Cache    *dataUsageCache `msg:"c"`
}

type nsScannerResp struct {
	Update *dataUsageEntry `msg:"u"`
	Final  *dataUsageCache `msg:"f"`

	setUploadForwardingMiddleware,
	// Add bucket forwarding middleware
	setBucketForwardingMiddleware,
	// Add new middlewares here.
}

// configureServer handler returns final handler for the http server.
func configureServerHandler(endpointServerPools EndpointServerPools) (http.Handler, error) {
	// Initialize router. `SkipClean(true)` stops minio/mux from
	// normalizing URL path minio/minio#3256

	canonicalRequestBytes := sha256.Sum256([]byte(canonicalRequest))
	stringToSign += hex.EncodeToString(canonicalRequestBytes[:])
	return stringToSign
}

// getSigningKey hmac seed to calculate final signature.
func getSigningKey(secretKey string, t time.Time, region string, stype serviceType) []byte {
	date := sumHMAC([]byte("AWS4"+secretKey), []byte(t.Format(yyyymmdd)))
	regionBytes := sumHMAC(date, []byte(region))

		if opts.EncryptFn != nil {
			fi.Checksum = opts.EncryptFn("object-checksum", fi.Checksum)
		}
	}
	delete(fi.Metadata, hash.MinIOMultipartChecksum) // Not needed in final object.

	// Save the final object size and modtime.
	fi.Size = objectSize
	fi.ModTime = opts.MTime
	if opts.MTime.IsZero() {
		fi.ModTime = UTCNow()
	}

	// Save successfully calculated md5sum.

//
// If an aggregation node is present as a descendant (when
// e.prop.isAggregation is true), we call evalNode on all child nodes,
// check for errors, but do not perform any combining of the results
// of child nodes. The final result row is returned after all rows are
// processed, and the `getAggregate` function is called.

func (e *AliasedExpression) evalNode(r Record, tableAlias string) (*Value, error) {
	return e.Expression.evalNode(r, tableAlias)

				updates <- cache.clone()

				lastSave = cache.Info.LastUpdate
			case v, ok := <-bucketResults:
				if !ok {
					// Save final state...
					cache.Info.NextCycle = wantCycle
					cache.Info.LastUpdate = time.Now()
					scannerLogOnceIf(ctx, cache.save(ctx, er, dataUsageCacheName), "nsscanner-channel-closed")
					updates <- cache.clone()

	"strings"
)

// newUnsignedV4ChunkedReader returns a new s3UnsignedChunkedReader that translates the data read from r
// out of HTTP "chunked" format before returning it.
// The s3ChunkedReader returns io.EOF when the final 0-length chunk is read.
func newUnsignedV4ChunkedReader(req *http.Request, trailer bool) (io.ReadCloser, APIErrorCode) {
	if trailer {
		// Discard anything unsigned.
		req.Trailer = make(http.Header)

			}
			fs.Delete(context.Background(), "voldir", test.objName, DeleteOptions{
				Recursive: false,
				Immediate: false,
			})
		})
	}
}

// Test to validate xlStorage behavior on windows when a non-final path component is a file.
func TestUNCPathENOTDIR(t *testing.T) {
	// Instantiate posix object to manage a disk
	dir := t.TempDir()

	fs, err := newLocalXLStorage(dir)
	if err != nil {
		t.Fatal(err)
	}

		// aggregation.
	}
	return nil
}

// getAggregate() implementation for each AST node follows. This is
// called after calling aggregateRow() on each input row, to calculate
// the final aggregate result.

func (e *FuncExpr) getAggregate() (*Value, error) {
	switch e.getFunctionName() {
	case aggFnCount:
		return FromInt(e.aggregate.runningCount), nil

	case aggFnAvg:

		nfi := fi
		if !nfi.IsRemote() {
			nfi.Data = nil
			nfi.Erasure.Index = 0
			nfi.Erasure.Checksums = nil
		}
		return nfi
	}

	// We write at temporary location and then rename to final location.
	tmpID := mustGetUUID()
	migrateDataDir := mustGetUUID()

	// Reorder so that we have data disks first and parity disks next.