minio/docs/bucket/versioning/xl-meta-to-json.go
2020-06-22 17:27:54 -07:00

122 lines
2.5 KiB
Go

/*
* MinIO Cloud Storage, (C) 2020 MinIO, Inc.
*
* 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 main
import (
"bytes"
"encoding/json"
"fmt"
"io"
"log"
"os"
"github.com/minio/cli"
"github.com/tinylib/msgp/msgp"
)
var xlHeader = [4]byte{'X', 'L', '2', ' '}
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...
{{if .VisibleFlags}}
GLOBAL FLAGS:
{{range .VisibleFlags}}{{.}}
{{end}}{{end}}
`
app.HideHelpCommand = true
app.Flags = []cli.Flag{
cli.BoolFlag{
Usage: "Print each file as a separate line without formatting",
Name: "ndjson",
},
}
app.Action = func(c *cli.Context) error {
if !c.Args().Present() {
cli.ShowAppHelp(c)
return nil
}
for _, file := range c.Args() {
var r io.Reader
switch file {
case "-":
r = os.Stdin
default:
f, err := os.Open(file)
if err != nil {
return err
}
defer f.Close()
r = f
}
// Read header
var tmp [4]byte
_, err := io.ReadFull(r, tmp[:])
if err != nil {
return err
}
if !bytes.Equal(tmp[:], xlHeader[:]) {
return fmt.Errorf("xlMeta: unknown XLv2 header, expected %v, got %v", xlHeader[:4], tmp[:4])
}
// Skip version check for now
_, err = io.ReadFull(r, tmp[:])
if err != nil {
return err
}
var buf bytes.Buffer
_, err = msgp.CopyToJSON(&buf, r)
if err != nil {
return err
}
if c.Bool("ndjson") {
fmt.Println(buf.String())
continue
}
var msi map[string]interface{}
dec := json.NewDecoder(&buf)
// Use number to preserve integers.
dec.UseNumber()
err = dec.Decode(&msi)
if err != nil {
return err
}
b, err := json.MarshalIndent(msi, "", " ")
if err != nil {
return err
}
fmt.Println(string(b))
}
return nil
}
err := app.Run(os.Args)
if err != nil {
log.Fatal(err)
}
}