minio/docs/debugging/xl-meta/main.go

512 lines
12 KiB
Go

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package main
import (
"bytes"
"encoding/binary"
"encoding/json"
"errors"
"fmt"
"io"
"io/ioutil"
"log"
"os"
"strings"
"github.com/klauspost/compress/zip"
"github.com/minio/cli"
"github.com/tinylib/msgp/msgp"
"github.com/yargevad/filepathx"
)
func main() {
app := cli.NewApp()
app.Copyright = "MinIO, Inc."
app.Usage = "xl.meta to JSON"
app.HideVersion = true
app.CustomAppHelpTemplate = `NAME:
{{.Name}} - {{.Usage}}
USAGE:
{{.Name}} {{if .VisibleFlags}}[FLAGS]{{end}} METAFILES...
Multiple files can be added. Files ending in '.zip' will be searched
for 'xl.meta' files. Wildcards are accepted: 'testdir/*.txt' will compress
all files in testdir ending with '.txt', directories can be wildcards
as well. 'testdir/*/*.txt' will match 'testdir/subdir/b.txt', double stars
means full recursive. 'testdir/**/xl.meta' will search for all xl.meta
recursively.
FLAGS:
{{range .VisibleFlags}}{{.}}
{{end}}
`
app.HideHelpCommand = true
app.Flags = []cli.Flag{
cli.BoolFlag{
Usage: "print each file as a separate line without formatting",
Name: "ndjson",
},
cli.BoolFlag{
Usage: "display inline data keys and sizes",
Name: "data",
},
cli.BoolFlag{
Usage: "export inline data",
Name: "export",
},
}
app.Action = func(c *cli.Context) error {
if !c.Args().Present() {
cli.ShowAppHelpAndExit(c, 1) // last argument is exit code
}
ndjson := c.Bool("ndjson")
decode := func(r io.Reader, file string) ([]byte, error) {
b, err := ioutil.ReadAll(r)
if err != nil {
return nil, err
}
b, _, minor, err := checkXL2V1(b)
if err != nil {
return nil, err
}
buf := bytes.NewBuffer(nil)
var data xlMetaInlineData
switch minor {
case 0:
_, err = msgp.CopyToJSON(buf, bytes.NewReader(b))
if err != nil {
return nil, err
}
case 1, 2:
v, b, err := msgp.ReadBytesZC(b)
if err != nil {
return nil, err
}
if _, nbuf, err := msgp.ReadUint32Bytes(b); err == nil {
// Read metadata CRC (added in v2, ignore if not found)
b = nbuf
}
_, err = msgp.CopyToJSON(buf, bytes.NewReader(v))
if err != nil {
return nil, err
}
data = b
case 3:
v, b, err := msgp.ReadBytesZC(b)
if err != nil {
return nil, err
}
if _, nbuf, err := msgp.ReadUint32Bytes(b); err == nil {
// Read metadata CRC (added in v2, ignore if not found)
b = nbuf
}
nVers, v, err := decodeXLHeaders(v)
if err != nil {
return nil, err
}
var versions = struct {
Versions []json.RawMessage
Headers []json.RawMessage
}{
Versions: make([]json.RawMessage, nVers),
Headers: make([]json.RawMessage, nVers),
}
err = decodeVersions(v, nVers, func(idx int, hdr, meta []byte) error {
var buf bytes.Buffer
if _, err := msgp.UnmarshalAsJSON(&buf, hdr); err != nil {
return err
}
versions.Headers[idx] = buf.Bytes()
buf = bytes.Buffer{}
if _, err := msgp.UnmarshalAsJSON(&buf, meta); err != nil {
return err
}
versions.Versions[idx] = buf.Bytes()
return nil
})
if err != nil {
return nil, err
}
enc := json.NewEncoder(buf)
if err := enc.Encode(versions); err != nil {
return nil, err
}
data = b
default:
return nil, fmt.Errorf("unknown metadata version %d", minor)
}
if c.Bool("data") {
b, err := data.json()
if err != nil {
return nil, err
}
buf = bytes.NewBuffer(b)
}
if c.Bool("export") {
file := strings.Map(func(r rune) rune {
switch {
case r >= 'a' && r <= 'z':
return r
case r >= 'A' && r <= 'Z':
return r
case r >= '0' && r <= '9':
return r
case strings.ContainsAny(string(r), "+=-_()!@."):
return r
default:
return '_'
}
}, file)
err := data.files(func(name string, data []byte) {
err = ioutil.WriteFile(fmt.Sprintf("%s-%s.data", file, name), data, os.ModePerm)
if err != nil {
fmt.Println(err)
}
})
if err != nil {
return nil, err
}
}
if ndjson {
return buf.Bytes(), nil
}
var msi map[string]interface{}
dec := json.NewDecoder(buf)
// Use number to preserve integers.
dec.UseNumber()
err = dec.Decode(&msi)
if err != nil {
return nil, err
}
b, err = json.MarshalIndent(msi, "", " ")
if err != nil {
return nil, err
}
return b, nil
}
args := c.Args()
if len(args) == 0 {
// If no args, assume xl.meta
args = []string{"xl.meta"}
}
var files []string
for _, pattern := range args {
if pattern == "-" {
files = append(files, pattern)
continue
}
found, err := filepathx.Glob(pattern)
if err != nil {
return err
}
if len(found) == 0 {
return fmt.Errorf("unable to find file %v", pattern)
}
files = append(files, found...)
}
if len(files) == 0 {
return fmt.Errorf("no files found")
}
multiple := len(files) > 1 || strings.HasSuffix(files[0], ".zip")
if multiple {
ndjson = true
fmt.Println("{")
}
hasWritten := false
for _, file := range files {
var r io.Reader
var sz int64
switch file {
case "-":
r = os.Stdin
default:
f, err := os.Open(file)
if err != nil {
return err
}
if st, err := f.Stat(); err == nil {
sz = st.Size()
}
defer f.Close()
r = f
}
if strings.HasSuffix(file, ".zip") {
zr, err := zip.NewReader(r.(io.ReaderAt), sz)
if err != nil {
return err
}
for _, file := range zr.File {
if !file.FileInfo().IsDir() && strings.HasSuffix(file.Name, "xl.meta") {
r, err := file.Open()
if err != nil {
return err
}
// Quote string...
b, _ := json.Marshal(file.Name)
if hasWritten {
fmt.Print(",\n")
}
fmt.Printf("\t%s: ", string(b))
b, err = decode(r, file.Name)
if err != nil {
return err
}
fmt.Print(string(b))
hasWritten = true
}
}
} else {
if multiple {
// Quote string...
b, _ := json.Marshal(file)
if hasWritten {
fmt.Print(",\n")
}
fmt.Printf("\t%s: ", string(b))
}
b, err := decode(r, file)
if err != nil {
return err
}
hasWritten = true
fmt.Print(string(b))
}
}
fmt.Println("")
if multiple {
fmt.Println("}")
}
return nil
}
err := app.Run(os.Args)
if err != nil {
log.Fatal(err)
}
}
var (
// XL header specifies the format
xlHeader = [4]byte{'X', 'L', '2', ' '}
// Current version being written.
xlVersionCurrent [4]byte
)
const (
// Breaking changes.
// Newer versions cannot be read by older software.
// This will prevent downgrades to incompatible versions.
xlVersionMajor = 1
// Non breaking changes.
// Bumping this is informational, but should be done
// if any change is made to the data stored, bumping this
// will allow to detect the exact version later.
xlVersionMinor = 1
)
func init() {
binary.LittleEndian.PutUint16(xlVersionCurrent[0:2], xlVersionMajor)
binary.LittleEndian.PutUint16(xlVersionCurrent[2:4], xlVersionMinor)
}
// checkXL2V1 will check if the metadata has correct header and is a known major version.
// The remaining payload and versions are returned.
func checkXL2V1(buf []byte) (payload []byte, major, minor uint16, err error) {
if len(buf) <= 8 {
return payload, 0, 0, fmt.Errorf("xlMeta: no data")
}
if !bytes.Equal(buf[:4], xlHeader[:]) {
return payload, 0, 0, fmt.Errorf("xlMeta: unknown XLv2 header, expected %v, got %v", xlHeader[:4], buf[:4])
}
if bytes.Equal(buf[4:8], []byte("1 ")) {
// Set as 1,0.
major, minor = 1, 0
} else {
major, minor = binary.LittleEndian.Uint16(buf[4:6]), binary.LittleEndian.Uint16(buf[6:8])
}
if major > xlVersionMajor {
return buf[8:], major, minor, fmt.Errorf("xlMeta: unknown major version %d found", major)
}
return buf[8:], major, minor, nil
}
const xlMetaInlineDataVer = 1
type xlMetaInlineData []byte
// afterVersion returns the payload after the version, if any.
func (x xlMetaInlineData) afterVersion() []byte {
if len(x) == 0 {
return x
}
return x[1:]
}
// versionOK returns whether the version is ok.
func (x xlMetaInlineData) versionOK() bool {
if len(x) == 0 {
return true
}
return x[0] > 0 && x[0] <= xlMetaInlineDataVer
}
func (x xlMetaInlineData) json() ([]byte, error) {
if len(x) == 0 {
return []byte("{}"), nil
}
if !x.versionOK() {
return nil, errors.New("xlMetaInlineData: unknown version")
}
sz, buf, err := msgp.ReadMapHeaderBytes(x.afterVersion())
if err != nil {
return nil, err
}
res := []byte("{")
for i := uint32(0); i < sz; i++ {
var key, val []byte
key, buf, err = msgp.ReadMapKeyZC(buf)
if err != nil {
return nil, err
}
if len(key) == 0 {
return nil, fmt.Errorf("xlMetaInlineData: key %d is length 0", i)
}
// Skip data...
val, buf, err = msgp.ReadBytesZC(buf)
if err != nil {
return nil, err
}
if i > 0 {
res = append(res, ',')
}
s := fmt.Sprintf(`"%s":%d`, string(key), len(val))
res = append(res, []byte(s)...)
}
res = append(res, '}')
return res, nil
}
// files returns files as callback.
func (x xlMetaInlineData) files(fn func(name string, data []byte)) error {
if len(x) == 0 {
return nil
}
if !x.versionOK() {
return errors.New("xlMetaInlineData: unknown version")
}
sz, buf, err := msgp.ReadMapHeaderBytes(x.afterVersion())
if err != nil {
return err
}
for i := uint32(0); i < sz; i++ {
var key, val []byte
key, buf, err = msgp.ReadMapKeyZC(buf)
if err != nil {
return err
}
if len(key) == 0 {
return fmt.Errorf("xlMetaInlineData: key %d is length 0", i)
}
// Read data...
val, buf, err = msgp.ReadBytesZC(buf)
if err != nil {
return err
}
// Call back.
fn(string(key), val)
}
return nil
}
const (
xlHeaderVersion = 2
xlMetaVersion = 1
)
func decodeXLHeaders(buf []byte) (versions int, b []byte, err error) {
hdrVer, buf, err := msgp.ReadUintBytes(buf)
if err != nil {
return 0, buf, err
}
metaVer, buf, err := msgp.ReadUintBytes(buf)
if err != nil {
return 0, buf, err
}
if hdrVer > xlHeaderVersion {
return 0, buf, fmt.Errorf("decodeXLHeaders: Unknown xl header version %d", metaVer)
}
if metaVer > xlMetaVersion {
return 0, buf, fmt.Errorf("decodeXLHeaders: Unknown xl meta version %d", metaVer)
}
versions, buf, err = msgp.ReadIntBytes(buf)
if err != nil {
return 0, buf, err
}
if versions < 0 {
return 0, buf, fmt.Errorf("decodeXLHeaders: Negative version count %d", versions)
}
return versions, buf, nil
}
// decodeVersions will decode a number of versions from a buffer
// and perform a callback for each version in order, newest first.
// Any non-nil error is returned.
func decodeVersions(buf []byte, versions int, fn func(idx int, hdr, meta []byte) error) (err error) {
var tHdr, tMeta []byte // Zero copy bytes
for i := 0; i < versions; i++ {
tHdr, buf, err = msgp.ReadBytesZC(buf)
if err != nil {
return err
}
tMeta, buf, err = msgp.ReadBytesZC(buf)
if err != nil {
return err
}
if err = fn(i, tHdr, tMeta); err != nil {
return err
}
}
return nil
}