milvus/internal/storage/local_chunk_manager.go
godchen c23236c50e
Fix chunk manager ci lint (#8779)
Signed-off-by: godchen <qingxiang.chen@zilliz.com>
2021-09-28 20:46:04 +08:00

105 lines
2.6 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 (
"errors"
"io/ioutil"
"os"
"path"
"golang.org/x/exp/mmap"
"github.com/milvus-io/milvus/internal/log"
)
// LocalChunkManager is responsible for read and write local file.
type LocalChunkManager struct {
localPath string
}
// NewLocalChunkManager create a new local manager object.
func NewLocalChunkManager(localPath string) *LocalChunkManager {
return &LocalChunkManager{
localPath: localPath,
}
}
// GetPath returns the path of local data if exist.
func (lcm *LocalChunkManager) GetPath(key string) (string, error) {
if !lcm.Exist(key) {
return "", errors.New("local file cannot be found with key:" + key)
}
path := path.Join(lcm.localPath, key)
return path, nil
}
// Write writes the data to local storage.
func (lcm *LocalChunkManager) Write(key string, content []byte) error {
filePath := path.Join(lcm.localPath, key)
dir := path.Dir(filePath)
if _, err := os.Stat(dir); os.IsNotExist(err) {
err := os.MkdirAll(dir, os.ModePerm)
if err != nil {
return err
}
}
err := ioutil.WriteFile(filePath, content, 0600)
if err != nil {
return err
}
return nil
}
// Exist checks whether chunk is saved to local storage.
func (lcm *LocalChunkManager) Exist(key string) bool {
path := path.Join(lcm.localPath, key)
_, err := os.Stat(path)
if err != nil {
return os.IsExist(err)
}
return true
}
// Read reads the local storage data if exist.
func (lcm *LocalChunkManager) Read(key string) ([]byte, error) {
filePath := path.Join(lcm.localPath, key)
file, err := os.Open(path.Clean(filePath))
if err != nil {
return nil, err
}
content, err := ioutil.ReadAll(file)
if err != nil {
return nil, err
}
return content, file.Close()
}
// ReadAt reads specific position data of local storage if exist.
func (lcm *LocalChunkManager) ReadAt(key string, p []byte, off int64) (n int, err error) {
path := path.Join(lcm.localPath, key)
at, err := mmap.Open(path)
defer func() {
if at != nil {
err = at.Close()
if err != nil {
log.Error(err.Error())
}
}
}()
if err != nil {
return 0, err
}
return at.ReadAt(p, off)
}