git-lfs/commands/command_pointer.go
2017-08-22 19:34:30 +02:00

134 lines
2.9 KiB
Go

package commands
import (
"bytes"
"crypto/sha256"
"encoding/hex"
"errors"
"fmt"
"io"
"os"
"github.com/git-lfs/git-lfs/git"
"github.com/git-lfs/git-lfs/lfs"
"github.com/spf13/cobra"
)
var (
pointerFile string
pointerCompare string
pointerStdin bool
)
func pointerCommand(cmd *cobra.Command, args []string) {
comparing := false
something := false
buildOid := ""
compareOid := ""
if len(pointerCompare) > 0 || pointerStdin {
comparing = true
}
if len(pointerFile) > 0 {
something = true
buildFile, err := os.Open(pointerFile)
if err != nil {
Error(err.Error())
os.Exit(1)
}
oidHash := sha256.New()
size, err := io.Copy(oidHash, buildFile)
buildFile.Close()
if err != nil {
Error(err.Error())
os.Exit(1)
}
ptr := lfs.NewPointer(hex.EncodeToString(oidHash.Sum(nil)), size, nil)
fmt.Fprintf(os.Stderr, "Git LFS pointer for %s\n\n", pointerFile)
buf := &bytes.Buffer{}
lfs.EncodePointer(io.MultiWriter(os.Stdout, buf), ptr)
if comparing {
buildOid, err = git.HashObject(bytes.NewReader(buf.Bytes()))
if err != nil {
Error(err.Error())
os.Exit(1)
}
fmt.Fprintf(os.Stderr, "\nGit blob OID: %s\n\n", buildOid)
}
} else {
comparing = false
}
if len(pointerCompare) > 0 || pointerStdin {
something = true
compFile, err := pointerReader()
if err != nil {
Error(err.Error())
os.Exit(1)
}
buf := &bytes.Buffer{}
tee := io.TeeReader(compFile, buf)
_, err = lfs.DecodePointer(tee)
compFile.Close()
pointerName := "STDIN"
if !pointerStdin {
pointerName = pointerCompare
}
fmt.Fprintf(os.Stderr, "Pointer from %s\n\n", pointerName)
if err != nil {
Error(err.Error())
os.Exit(1)
}
fmt.Fprintf(os.Stderr, buf.String())
if comparing {
compareOid, err = git.HashObject(bytes.NewReader(buf.Bytes()))
if err != nil {
Error(err.Error())
os.Exit(1)
}
fmt.Fprintf(os.Stderr, "\nGit blob OID: %s\n", compareOid)
}
}
if comparing && buildOid != compareOid {
fmt.Fprintf(os.Stderr, "\nPointers do not match\n")
os.Exit(1)
}
if !something {
Error("Nothing to do!")
os.Exit(1)
}
}
func pointerReader() (io.ReadCloser, error) {
if len(pointerCompare) > 0 {
if pointerStdin {
return nil, errors.New("Cannot read from STDIN and --pointer.")
}
return os.Open(pointerCompare)
}
requireStdin("The --stdin flag expects a pointer file from STDIN.")
return os.Stdin, nil
}
func init() {
RegisterCommand("pointer", pointerCommand, func(cmd *cobra.Command) {
cmd.Flags().StringVarP(&pointerFile, "file", "f", "", "Path to a local file to generate the pointer from.")
cmd.Flags().StringVarP(&pointerCompare, "pointer", "p", "", "Path to a local file containing a pointer built by another Git LFS implementation.")
cmd.Flags().BoolVarP(&pointerStdin, "stdin", "", false, "Read a pointer built by another Git LFS implementation through STDIN.")
})
}