-
Notifications
You must be signed in to change notification settings - Fork 5.7k
/
compress.go
175 lines (156 loc) · 4.78 KB
/
compress.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
// Copyright 2020 PingCAP, Inc. Licensed under Apache-2.0.
package storage
import (
"bytes"
"context"
"io"
"github.com/pingcap/errors"
berrors "github.com/pingcap/tidb/br/pkg/errors"
)
type withCompression struct {
ExternalStorage
compressType CompressType
decompressCfg DecompressConfig
}
// WithCompression returns an ExternalStorage with compress option
func WithCompression(inner ExternalStorage, compressionType CompressType, cfg DecompressConfig) ExternalStorage {
if compressionType == NoCompression {
return inner
}
return &withCompression{
ExternalStorage: inner,
compressType: compressionType,
decompressCfg: cfg,
}
}
func (w *withCompression) Create(ctx context.Context, name string, o *WriterOption) (ExternalFileWriter, error) {
writer, err := w.ExternalStorage.Create(ctx, name, o)
if err != nil {
return nil, errors.Trace(err)
}
// some implementation already wrap the writer, so we need to unwrap it
if bw, ok := writer.(*bufferedWriter); ok {
writer = bw.writer
}
compressedWriter := newBufferedWriter(writer, hardcodedS3ChunkSize, w.compressType)
return compressedWriter, nil
}
func (w *withCompression) Open(ctx context.Context, path string, o *ReaderOption) (ExternalFileReader, error) {
fileReader, err := w.ExternalStorage.Open(ctx, path, o)
if err != nil {
return nil, errors.Trace(err)
}
uncompressReader, err := InterceptDecompressReader(fileReader, w.compressType, w.decompressCfg)
if err != nil {
return nil, errors.Trace(err)
}
return uncompressReader, nil
}
func (w *withCompression) WriteFile(ctx context.Context, name string, data []byte) error {
bf := bytes.NewBuffer(make([]byte, 0, len(data)))
compressBf := newCompressWriter(w.compressType, bf)
_, err := compressBf.Write(data)
if err != nil {
return errors.Trace(err)
}
err = compressBf.Close()
if err != nil {
return errors.Trace(err)
}
return w.ExternalStorage.WriteFile(ctx, name, bf.Bytes())
}
func (w *withCompression) ReadFile(ctx context.Context, name string) ([]byte, error) {
data, err := w.ExternalStorage.ReadFile(ctx, name)
if err != nil {
return data, errors.Trace(err)
}
bf := bytes.NewBuffer(data)
compressBf, err := newCompressReader(w.compressType, w.decompressCfg, bf)
if err != nil {
return nil, err
}
return io.ReadAll(compressBf)
}
// compressReader is a wrapper for compress.Reader
type compressReader struct {
io.Reader
io.Seeker
io.Closer
}
// InterceptDecompressReader intercepts the reader and wraps it with a decompress
// reader on the given ExternalFileReader. Note that the returned
// ExternalFileReader does not have the property that Seek(0, io.SeekCurrent)
// equals total bytes Read() if the decompress reader is used.
func InterceptDecompressReader(
fileReader ExternalFileReader,
compressType CompressType,
cfg DecompressConfig,
) (ExternalFileReader, error) {
if compressType == NoCompression {
return fileReader, nil
}
r, err := newCompressReader(compressType, cfg, fileReader)
if err != nil {
return nil, errors.Trace(err)
}
return &compressReader{
Reader: r,
Closer: fileReader,
Seeker: fileReader,
}, nil
}
func NewLimitedInterceptReader(
fileReader ExternalFileReader,
compressType CompressType,
cfg DecompressConfig,
n int64,
) (ExternalFileReader, error) {
newFileReader := fileReader
if n < 0 {
return nil, errors.Annotatef(berrors.ErrStorageInvalidConfig, "compressReader doesn't support negative limit, n: %d", n)
} else if n > 0 {
newFileReader = &compressReader{
Reader: io.LimitReader(fileReader, n),
Seeker: fileReader,
Closer: fileReader,
}
}
return InterceptDecompressReader(newFileReader, compressType, cfg)
}
func (c *compressReader) Seek(offset int64, whence int) (int64, error) {
// only support get original reader's current offset
if offset == 0 && whence == io.SeekCurrent {
return c.Seeker.Seek(offset, whence)
}
return int64(0), errors.Annotatef(berrors.ErrStorageInvalidConfig, "compressReader doesn't support Seek now, offset %d, whence %d", offset, whence)
}
func (c *compressReader) Close() error {
err := c.Closer.Close()
return err
}
func (c *compressReader) GetFileSize() (int64, error) {
return 0, errors.Annotatef(berrors.ErrUnsupportedOperation, "compressReader doesn't support GetFileSize now")
}
type flushStorageWriter struct {
writer io.Writer
flusher flusher
closer io.Closer
}
func (w *flushStorageWriter) Write(_ context.Context, data []byte) (int, error) {
n, err := w.writer.Write(data)
return n, errors.Trace(err)
}
func (w *flushStorageWriter) Close(_ context.Context) error {
err := w.flusher.Flush()
if err != nil {
return errors.Trace(err)
}
return w.closer.Close()
}
func newFlushStorageWriter(writer io.Writer, flusher2 flusher, closer io.Closer) *flushStorageWriter {
return &flushStorageWriter{
writer: writer,
flusher: flusher2,
closer: closer,
}
}