mirror of
https://gitee.com/milvus-io/milvus.git
synced 2024-12-01 11:29:48 +08:00
94 lines
2.4 KiB
Go
94 lines
2.4 KiB
Go
// Copyright (C) 2019-2020 Zilliz. All rights reserved.
|
|
//
|
|
// Licensed 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"
|
|
"strconv"
|
|
|
|
"errors"
|
|
)
|
|
|
|
type BinlogReader struct {
|
|
magicNumber int32
|
|
descriptorEvent
|
|
buffer *bytes.Buffer
|
|
eventList []*EventReader
|
|
isClose bool
|
|
}
|
|
|
|
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
|
|
}
|
|
eventReader, err := newEventReader(reader.descriptorEvent.PayloadDataType, reader.buffer)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
reader.eventList = append(reader.eventList, eventReader)
|
|
return eventReader, nil
|
|
}
|
|
|
|
func (reader *BinlogReader) readMagicNumber() (int32, error) {
|
|
if err := binary.Read(reader.buffer, binary.LittleEndian, &reader.magicNumber); err != nil {
|
|
return -1, err
|
|
}
|
|
if reader.magicNumber != MagicNumber {
|
|
return -1, fmt.Errorf("parse magic number failed, expected: %s, actual: %s", strconv.Itoa(int(MagicNumber)), strconv.Itoa(int(reader.magicNumber)))
|
|
}
|
|
|
|
return reader.magicNumber, nil
|
|
}
|
|
|
|
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 (reader *BinlogReader) Close() error {
|
|
if reader.isClose {
|
|
return nil
|
|
}
|
|
for _, e := range reader.eventList {
|
|
if err := e.Close(); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
reader.isClose = true
|
|
return nil
|
|
}
|
|
|
|
func NewBinlogReader(data []byte) (*BinlogReader, error) {
|
|
reader := &BinlogReader{
|
|
buffer: bytes.NewBuffer(data),
|
|
eventList: []*EventReader{},
|
|
isClose: false,
|
|
}
|
|
|
|
if _, err := reader.readMagicNumber(); err != nil {
|
|
return nil, err
|
|
}
|
|
if _, err := reader.readDescriptorEvent(); err != nil {
|
|
return nil, err
|
|
}
|
|
return reader, nil
|
|
}
|