mirror of
https://gitee.com/milvus-io/milvus.git
synced 2024-12-05 21:39:19 +08:00
ef3ced8138
#34176 --------- Signed-off-by: lixinguo <xinguo.li@zilliz.com> Co-authored-by: lixinguo <xinguo.li@zilliz.com>
133 lines
3.6 KiB
Go
133 lines
3.6 KiB
Go
// Licensed to the LF AI & Data foundation under one
|
|
// or more contributor license agreements. See the NOTICE file
|
|
// distributed with this work for additional information
|
|
// regarding copyright ownership. The ASF licenses this file
|
|
// to you under the Apache License, Version 2.0 (the
|
|
// "License"); you may not use this file except in compliance
|
|
// with the License. You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package storage
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/binary"
|
|
"fmt"
|
|
"io"
|
|
|
|
"github.com/cockroachdb/errors"
|
|
|
|
"github.com/milvus-io/milvus/pkg/common"
|
|
)
|
|
|
|
// BinlogReader is an object to read binlog file. Binlog file's format can be
|
|
// found in design docs.
|
|
type BinlogReader struct {
|
|
magicNumber int32
|
|
descriptorEvent
|
|
buffer *bytes.Buffer
|
|
eventReader *EventReader
|
|
isClose bool
|
|
}
|
|
|
|
// NextEventReader iters all events reader to read the binlog file.
|
|
func (reader *BinlogReader) NextEventReader() (*EventReader, error) {
|
|
if reader.isClose {
|
|
return nil, errors.New("bin log reader is closed")
|
|
}
|
|
if reader.buffer.Len() <= 0 {
|
|
return nil, nil
|
|
}
|
|
// close the previous reader
|
|
if reader.eventReader != nil {
|
|
reader.eventReader.Close()
|
|
}
|
|
nullable, err := reader.descriptorEvent.GetNullable()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
reader.eventReader, err = newEventReader(reader.descriptorEvent.PayloadDataType, reader.buffer, nullable)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return reader.eventReader, nil
|
|
}
|
|
|
|
func (reader *BinlogReader) readMagicNumber() (int32, error) {
|
|
var err error
|
|
reader.magicNumber, err = readMagicNumber(reader.buffer)
|
|
return reader.magicNumber, err
|
|
}
|
|
|
|
func (reader *BinlogReader) readDescriptorEvent() (*descriptorEvent, error) {
|
|
event, err := ReadDescriptorEvent(reader.buffer)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
reader.descriptorEvent = *event
|
|
return &reader.descriptorEvent, nil
|
|
}
|
|
|
|
func readMagicNumber(buffer io.Reader) (int32, error) {
|
|
var magicNumber int32
|
|
if err := binary.Read(buffer, common.Endian, &magicNumber); err != nil {
|
|
return -1, err
|
|
}
|
|
if magicNumber != MagicNumber {
|
|
return -1, fmt.Errorf("parse magic number failed, expected: %d, actual: %d", MagicNumber, magicNumber)
|
|
}
|
|
|
|
return magicNumber, nil
|
|
}
|
|
|
|
// ReadDescriptorEvent reads a descriptorEvent from buffer
|
|
func ReadDescriptorEvent(buffer io.Reader) (*descriptorEvent, error) {
|
|
header, err := readDescriptorEventHeader(buffer)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
data, err := readDescriptorEventData(buffer)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &descriptorEvent{
|
|
descriptorEventHeader: *header,
|
|
descriptorEventData: *data,
|
|
}, nil
|
|
}
|
|
|
|
// Close closes the BinlogReader object.
|
|
// It mainly calls the Close method of the internal events, reclaims resources, and marks itself as closed.
|
|
func (reader *BinlogReader) Close() {
|
|
if reader.isClose {
|
|
return
|
|
}
|
|
if reader.eventReader != nil {
|
|
reader.eventReader.Close()
|
|
}
|
|
reader.isClose = true
|
|
}
|
|
|
|
// NewBinlogReader creates binlogReader to read binlog file.
|
|
func NewBinlogReader(data []byte) (*BinlogReader, error) {
|
|
reader := &BinlogReader{
|
|
buffer: bytes.NewBuffer(data),
|
|
isClose: false,
|
|
}
|
|
|
|
if _, err := reader.readMagicNumber(); err != nil {
|
|
return nil, err
|
|
}
|
|
if _, err := reader.readDescriptorEvent(); err != nil {
|
|
return nil, err
|
|
}
|
|
return reader, nil
|
|
}
|