storj/pkg/piecestore/pstore.go
Egon Elbre 3f3209c8d5
fixes to piecestore and psdb (#1380)
* replace direct reference with an interface in various places
* hide piecePath
* ensure psserver tests don't use path
* ensure psserver tests don't use sql queries directly
2019-03-01 07:46:16 +02:00

140 lines
3.1 KiB
Go

// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package pstore
import (
"context"
"io"
"os"
"path/filepath"
"github.com/shirou/gopsutil/disk"
"github.com/zeebo/errs"
"storj.io/storj/pkg/ranger"
)
// IDLength -- Minimum ID length
const IDLength = 20
// Errors
var (
Error = errs.Class("piecestore error")
)
// Storage stores piecestore pieces
type Storage struct {
dir string
}
// NewStorage creates database for storing pieces
func NewStorage(dir string) *Storage {
return &Storage{dir}
}
// Close closes resources
func (storage *Storage) Close() error { return nil }
// DiskInfo contains statistics about the disk
type DiskInfo struct {
AvailableSpace int64 // TODO: use memory.Size
}
// Info returns information about the current state of the dir
func (storage *Storage) Info() (DiskInfo, error) {
rootPath := filepath.Dir(filepath.Clean(storage.dir))
diskSpace, err := disk.Usage(rootPath)
if err != nil {
return DiskInfo{}, Error.Wrap(err)
}
return DiskInfo{
AvailableSpace: int64(diskSpace.Free),
}, nil
}
// piecePath creates piece storage path from id and dir
func (storage *Storage) piecePath(pieceID string) (string, error) {
if len(pieceID) < IDLength {
return "", Error.New("invalid id length")
}
folder1, folder2, filename := pieceID[0:2], pieceID[2:4], pieceID[4:]
return filepath.Join(storage.dir, folder1, folder2, filename), nil
}
// Size returns piece size.
func (storage *Storage) Size(pieceID string) (int64, error) {
path, err := storage.piecePath(pieceID)
if err != nil {
return 0, err
}
fileInfo, err := os.Stat(path)
if err != nil {
return 0, Error.Wrap(err)
}
return fileInfo.Size(), nil
}
// Writer returns a writer that can be used to store piece.
func (storage *Storage) Writer(pieceID string) (io.WriteCloser, error) {
path, err := storage.piecePath(pieceID)
if err != nil {
return nil, err
}
if err = os.MkdirAll(filepath.Dir(path), 0700); err != nil {
return nil, Error.Wrap(err)
}
file, err := os.OpenFile(path, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0600)
if err != nil {
return nil, Error.Wrap(err)
}
return file, nil
}
// Reader returns a reader for the specified piece at the location
func (storage *Storage) Reader(ctx context.Context, pieceID string, offset int64, length int64) (io.ReadCloser, error) {
path, err := storage.piecePath(pieceID)
if err != nil {
return nil, err
}
info, err := os.Stat(path)
if err != nil {
return nil, err
}
if offset >= info.Size() || offset < 0 {
return nil, Error.New("invalid offset: %v", offset)
}
if length <= -1 {
length = info.Size()
}
// If trying to read past the end of the file, just read to the end
if info.Size() < offset+length {
length = info.Size() - offset
}
rr, err := ranger.FileRanger(path)
if err != nil {
return nil, Error.Wrap(err)
}
r, err := rr.Range(ctx, offset, length)
return r, Error.Wrap(err)
}
// Delete deletes piece from storage
func (storage *Storage) Delete(pieceID string) error {
path, err := storage.piecePath(pieceID)
if err != nil {
return Error.Wrap(err)
}
err = os.Remove(path)
if os.IsNotExist(err) {
err = nil
}
return Error.Wrap(err)
}