lotus/node/impl/client/import.go
2021-07-15 17:50:35 +05:30

123 lines
4.4 KiB
Go

package client
import (
"context"
"os"
"github.com/filecoin-project/go-fil-markets/filestorecaradapter"
bstore "github.com/filecoin-project/lotus/blockstore"
"github.com/filecoin-project/lotus/build"
"github.com/filecoin-project/lotus/node/repo/importmgr"
"github.com/ipfs/go-blockservice"
"github.com/ipfs/go-cid"
"github.com/ipfs/go-cidutil"
"github.com/ipfs/go-datastore"
ds_sync "github.com/ipfs/go-datastore/sync"
"github.com/ipfs/go-filestore"
chunker "github.com/ipfs/go-ipfs-chunker"
offline "github.com/ipfs/go-ipfs-exchange-offline"
files2 "github.com/ipfs/go-ipfs-files"
ipld "github.com/ipfs/go-ipld-format"
"github.com/ipfs/go-merkledag"
"github.com/ipfs/go-unixfs/importer/balanced"
ihelper "github.com/ipfs/go-unixfs/importer/helpers"
"golang.org/x/xerrors"
)
// importNormalFileToFilestoreCARv2 transforms the client's "normal file" to a Unixfs IPLD DAG and writes out the DAG to a CARv2 file
// that can be used to back a filestore.
func (a *API) importNormalFileToFilestoreCARv2(ctx context.Context, importID importmgr.ImportID, inputFilePath string, outputCARv2Path string) (c cid.Cid, finalErr error) {
// TODO: We've currently put in a hack to create the Unixfs DAG as a CARv2 without using Badger.
// We first create the Unixfs DAG using a filestore to get the root of the Unixfs DAG.
// We can't create the UnixfsDAG right away using a CARv2 read-write blockstore as the blockstore
// needs the root of the DAG during instantiation to write out a valid CARv2 file.
//
// In the second pass, we create a CARv2 file with the root present using the root node we get in the above step.
// This hack should be fixed when CARv2 allows specifying the root AFTER finishing the CARv2 streaming write.
fm := filestore.NewFileManager(ds_sync.MutexWrap(datastore.NewMapDatastore()), "/")
fm.AllowFiles = true
fstore := filestore.NewFilestore(bstore.NewMemorySync(), fm)
bsvc := blockservice.New(fstore, offline.Exchange(fstore))
defer bsvc.Close() //nolint:errcheck
// ---- First Pass --- Write out the UnixFS DAG to a rootless CARv2 file by instantiating a read-write CARv2 blockstore without the root.
root, err := importNormalFileToUnixfsDAG(ctx, inputFilePath, merkledag.NewDAGService(bsvc))
if err != nil {
return cid.Undef, xerrors.Errorf("failed to import file to store: %w", err)
}
//------ Second Pass --- Now that we have the root of the Unixfs DAG -> write out the Unixfs DAG to a CARv2 file with the root present by using a
// filestore backed by a read-write CARv2 blockstore.
fsb, err := filestorecaradapter.NewReadWriteFileStore(outputCARv2Path, []cid.Cid{root})
if err != nil {
return cid.Undef, xerrors.Errorf("failed to create a CARv2 read-write blockstore: %w", err)
}
defer fsb.Close() //nolint:errcheck
bsvc = blockservice.New(fsb, offline.Exchange(fsb))
root2, err := importNormalFileToUnixfsDAG(ctx, inputFilePath, merkledag.NewDAGService(bsvc))
if err != nil {
return cid.Undef, xerrors.Errorf("failed to create Unixfs DAG with CARv2 blockstore: %w", err)
}
if root != root2 {
return cid.Undef, xerrors.New("roots do not match")
}
return root, nil
}
// importNormalFileToUnixfsDAG transforms a client's normal file to a UnixfsDAG and imports the DAG to the given DAG service.
func importNormalFileToUnixfsDAG(ctx context.Context, inputFilePath string, dag ipld.DAGService) (cid.Cid, error) {
f, err := os.Open(inputFilePath)
if err != nil {
return cid.Undef, xerrors.Errorf("failed to open input file: %w", err)
}
defer f.Close() //nolint:errcheck
stat, err := f.Stat()
if err != nil {
return cid.Undef, xerrors.Errorf("failed to stat file :%w", err)
}
file, err := files2.NewReaderPathFile(inputFilePath, f, stat)
if err != nil {
return cid.Undef, xerrors.Errorf("failed to create reader path file: %w", err)
}
bufDs := ipld.NewBufferedDAG(ctx, dag)
prefix, err := merkledag.PrefixForCidVersion(1)
if err != nil {
return cid.Undef, err
}
prefix.MhType = DefaultHashFunction
params := ihelper.DagBuilderParams{
Maxlinks: build.UnixfsLinksPerLevel,
RawLeaves: true,
CidBuilder: cidutil.InlineBuilder{
Builder: prefix,
Limit: 126,
},
Dagserv: bufDs,
NoCopy: true,
}
db, err := params.New(chunker.NewSizeSplitter(file, int64(build.UnixfsChunkSize)))
if err != nil {
return cid.Undef, err
}
nd, err := balanced.Layout(db)
if err != nil {
return cid.Undef, err
}
if err := bufDs.Commit(); err != nil {
return cid.Undef, err
}
return nd.Cid(), nil
}