lotus/cmd/lotus-shed/export-car.go
2023-02-15 11:09:24 -05:00

120 lines
2.6 KiB
Go

package main
import (
"fmt"
"io"
"os"
"github.com/ipfs/go-blockservice"
"github.com/ipfs/go-cid"
offline "github.com/ipfs/go-ipfs-exchange-offline"
format "github.com/ipfs/go-ipld-format"
"github.com/ipfs/go-merkledag"
"github.com/ipld/go-car"
"github.com/urfave/cli/v2"
"golang.org/x/xerrors"
"github.com/filecoin-project/lotus/blockstore"
"github.com/filecoin-project/lotus/chain/types"
lcli "github.com/filecoin-project/lotus/cli"
"github.com/filecoin-project/lotus/node/repo"
)
func carWalkFunc(nd format.Node) (out []*format.Link, err error) {
for _, link := range nd.Links() {
if link.Cid.Prefix().Codec == cid.FilCommitmentSealed || link.Cid.Prefix().Codec == cid.FilCommitmentUnsealed {
continue
}
out = append(out, link)
}
return out, nil
}
var exportCarCmd = &cli.Command{
Name: "export-car",
Description: "Export a car from repo",
Flags: []cli.Flag{
&cli.StringFlag{
Name: "repo",
Value: "~/.lotus",
},
},
ArgsUsage: "[outfile] [root cid]",
Action: func(cctx *cli.Context) error {
if cctx.NArg() != 2 {
return lcli.IncorrectNumArgs(cctx)
}
outfile := cctx.Args().First()
var roots []cid.Cid
for _, arg := range cctx.Args().Tail() {
c, err := cid.Decode(arg)
if err != nil {
return err
}
roots = append(roots, c)
}
ctx := lcli.ReqContext(cctx)
r, err := repo.NewFS(cctx.String("repo"))
if err != nil {
return xerrors.Errorf("opening fs repo: %w", err)
}
exists, err := r.Exists()
if err != nil {
return err
}
if !exists {
return xerrors.Errorf("lotus repo doesn't exist")
}
var bs blockstore.Blockstore
lr, err := r.Lock(repo.FullNode)
if err == nil {
bs, err = lr.Blockstore(ctx, repo.UniversalBlockstore)
if err != nil {
return fmt.Errorf("failed to open blockstore: %w", err)
}
defer lr.Close() //nolint:errcheck
} else {
api, closer, err := lcli.GetFullNodeAPI(cctx)
if err != nil {
return err
}
defer closer()
bs = blockstore.NewAPIBlockstore(api)
}
fi, err := os.Create(outfile)
if err != nil {
return xerrors.Errorf("opening the output file: %w", err)
}
defer fi.Close() //nolint:errcheck
defer func() {
if c, ok := bs.(io.Closer); ok {
if err := c.Close(); err != nil {
log.Warnf("failed to close blockstore: %s", err)
}
}
}()
dag := merkledag.NewDAGService(blockservice.New(bs, offline.Exchange(bs)))
err = car.WriteCarWithWalker(ctx, dag, roots, fi, carWalkFunc)
if err != nil {
return err
}
sz, err := fi.Seek(0, io.SeekEnd)
if err != nil {
return err
}
fmt.Printf("done %s\n", types.SizeStr(types.NewInt(uint64(sz))))
return nil
},
}