[#63] Simplify multiObjectReader and add tests

Signed-off-by: Denis Kirillov <d.kirillov@yadro.com>
This commit is contained in:
Denis Kirillov 2023-07-18 14:48:33 +03:00
parent 631b7f67b4
commit 1a09041cd1
3 changed files with 227 additions and 32 deletions

View file

@ -6,6 +6,7 @@ import (
"fmt"
"io"
"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/data"
oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
)
@ -14,54 +15,124 @@ type partObj struct {
Size uint64
}
type readerInitiator interface {
initFrostFSObjectPayloadReader(ctx context.Context, p getFrostFSParams) (io.Reader, error)
}
// implements io.Reader of payloads of the object list stored in the FrostFS network.
type multiObjectReader struct {
ctx context.Context
layer *layer
layer readerInitiator
off, ln uint64
startPartOffset uint64
endPartLength uint64
prm getFrostFSParams
curIndex int
curReader io.Reader
parts []partObj
}
type multiObjectReaderConfig struct {
layer readerInitiator
// the offset of complete object and total size to read
off, ln uint64
bktInfo *data.BucketInfo
parts []partObj
}
var (
errOffsetIsOutOfRange = errors.New("offset is out of payload range")
errLengthIsOutOfRange = errors.New("length is out of payload range")
errEmptyPartsList = errors.New("empty parts list")
errorZeroRangeLength = errors.New("zero range length")
)
func newMultiObjectReader(ctx context.Context, cfg multiObjectReaderConfig) (*multiObjectReader, error) {
if len(cfg.parts) == 0 {
return nil, errEmptyPartsList
}
r := &multiObjectReader{
ctx: ctx,
layer: cfg.layer,
prm: getFrostFSParams{
bktInfo: cfg.bktInfo,
},
parts: cfg.parts,
}
if cfg.off+cfg.ln == 0 {
return r, nil
}
if cfg.off > 0 && cfg.ln == 0 {
return nil, errorZeroRangeLength
}
startPartIndex, startPartOffset := findStartPart(cfg)
if startPartIndex == -1 {
return nil, errOffsetIsOutOfRange
}
r.startPartOffset = startPartOffset
endPartIndex, endPartLength := findEndPart(cfg)
if endPartIndex == -1 {
return nil, errLengthIsOutOfRange
}
r.endPartLength = endPartLength
r.parts = cfg.parts[startPartIndex : endPartIndex+1]
return r, nil
}
func findStartPart(cfg multiObjectReaderConfig) (index int, offset uint64) {
return findPartByPosition(cfg.off, cfg.parts)
}
func findEndPart(cfg multiObjectReaderConfig) (index int, length uint64) {
return findPartByPosition(cfg.off+cfg.ln, cfg.parts)
}
func findPartByPosition(position uint64, parts []partObj) (index int, positionInPart uint64) {
for i, part := range parts {
if position <= part.Size {
return i, position
}
position -= part.Size
}
return -1, 0
}
func (x *multiObjectReader) Read(p []byte) (n int, err error) {
if x.curReader != nil {
n, err = x.curReader.Read(p)
if !errors.Is(err, io.EOF) {
return n, err
}
x.curIndex++
}
if len(x.parts) == 0 {
if x.curIndex == len(x.parts) {
return n, io.EOF
}
for x.off != 0 {
if x.parts[0].Size < x.off {
x.parts = x.parts[1:]
x.off -= x.parts[0].Size
} else {
x.prm.off = x.off
x.off = 0
}
x.prm.oid = x.parts[x.curIndex].OID
if x.curIndex == 0 {
x.prm.off = x.startPartOffset
x.prm.ln = x.parts[x.curIndex].Size - x.startPartOffset
}
x.prm.oid = x.parts[0].OID
if x.ln != 0 {
if x.parts[0].Size < x.prm.off+x.ln {
x.prm.ln = x.parts[0].Size - x.prm.off
x.ln -= x.prm.ln
} else {
x.prm.ln = x.ln
x.ln = 0
x.parts = x.parts[:1]
}
if x.curIndex == len(x.parts)-1 {
x.prm.ln = x.endPartLength - x.prm.off
}
x.curReader, err = x.layer.initFrostFSObjectPayloadReader(x.ctx, x.prm)
@ -72,8 +143,6 @@ func (x *multiObjectReader) Read(p []byte) (n int, err error) {
x.prm.off = 0
x.prm.ln = 0
x.parts = x.parts[1:]
next, err := x.Read(p[n:])
return n + next, err

View file

@ -0,0 +1,127 @@
package layer
import (
"bytes"
"context"
"errors"
"fmt"
"io"
"testing"
oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
oidtest "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id/test"
"github.com/stretchr/testify/require"
)
type readerInitiatorMock struct {
parts map[oid.ID][]byte
}
func (r *readerInitiatorMock) initFrostFSObjectPayloadReader(_ context.Context, p getFrostFSParams) (io.Reader, error) {
partPayload, ok := r.parts[p.oid]
if !ok {
return nil, errors.New("part not found")
}
if p.off+p.ln == 0 {
return bytes.NewReader(partPayload), nil
}
if p.off > uint64(len(partPayload)-1) {
return nil, fmt.Errorf("invalid offset: %d/%d", p.off, len(partPayload))
}
if p.off+p.ln > uint64(len(partPayload)) {
return nil, fmt.Errorf("invalid range: %d-%d/%d", p.off, p.off+p.ln, len(partPayload))
}
return bytes.NewReader(partPayload[p.off : p.off+p.ln]), nil
}
func prepareDataReader() ([]byte, []partObj, *readerInitiatorMock) {
mockInitReader := &readerInitiatorMock{
parts: map[oid.ID][]byte{
oidtest.ID(): []byte("first part 1"),
oidtest.ID(): []byte("second part 2"),
oidtest.ID(): []byte("third part 3"),
},
}
var fullPayload []byte
parts := make([]partObj, 0, len(mockInitReader.parts))
for id, payload := range mockInitReader.parts {
parts = append(parts, partObj{OID: id, Size: uint64(len(payload))})
fullPayload = append(fullPayload, payload...)
}
return fullPayload, parts, mockInitReader
}
func TestMultiReader(t *testing.T) {
ctx := context.Background()
fullPayload, parts, mockInitReader := prepareDataReader()
for _, tc := range []struct {
name string
off uint64
ln uint64
err error
}{
{
name: "simple read all",
},
{
name: "simple read with length",
ln: uint64(len(fullPayload)),
},
{
name: "middle of parts",
off: parts[0].Size + 2,
ln: 4,
},
{
name: "first and second",
off: parts[0].Size - 4,
ln: 8,
},
{
name: "first and third",
off: parts[0].Size - 4,
ln: parts[1].Size + 8,
},
{
name: "offset out of range",
off: uint64(len(fullPayload) + 1),
ln: 1,
err: errOffsetIsOutOfRange,
},
{
name: "zero length",
off: parts[1].Size + 1,
ln: 0,
err: errorZeroRangeLength,
},
} {
t.Run(tc.name, func(t *testing.T) {
multiReader, err := newMultiObjectReader(ctx, multiObjectReaderConfig{
layer: mockInitReader,
parts: parts,
off: tc.off,
ln: tc.ln,
})
require.ErrorIs(t, err, tc.err)
if tc.err == nil {
off := tc.off
ln := tc.ln
if off+ln == 0 {
ln = uint64(len(fullPayload))
}
data, err := io.ReadAll(multiReader)
require.NoError(t, err)
require.Equal(t, fullPayload[off:off+ln], data)
}
})
}
}

View file

@ -143,14 +143,13 @@ func (n *layer) initObjectPayloadReader(ctx context.Context, p getParams) (io.Re
}
}
return &multiObjectReader{
ctx: ctx,
off: p.off,
ln: p.ln,
layer: n,
parts: objParts,
prm: getFrostFSParams{bktInfo: p.bktInfo},
}, nil
return newMultiObjectReader(ctx, multiObjectReaderConfig{
layer: n,
off: p.off,
ln: p.ln,
parts: objParts,
bktInfo: p.bktInfo,
})
}
// initializes payload reader of the FrostFS object.