lotus/itests/kit/files.go
2021-11-12 09:43:42 +01:00

166 lines
4.3 KiB
Go

package kit
import (
"bufio"
"bytes"
"context"
"io"
"math/rand"
"os"
"testing"
"github.com/ipfs/go-blockservice"
"github.com/ipfs/go-cid"
cidutil "github.com/ipfs/go-cidutil"
ds "github.com/ipfs/go-datastore"
dssync "github.com/ipfs/go-datastore/sync"
bstore "github.com/ipfs/go-ipfs-blockstore"
chunk "github.com/ipfs/go-ipfs-chunker"
offline "github.com/ipfs/go-ipfs-exchange-offline"
files "github.com/ipfs/go-ipfs-files"
ipldformat "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"
"github.com/ipld/go-car"
"github.com/minio/blake2b-simd"
mh "github.com/multiformats/go-multihash"
"github.com/stretchr/testify/require"
)
const unixfsChunkSize int64 = 1 << 10
var defaultHashFunction = uint64(mh.BLAKE2B_MIN + 31)
// CreateRandomFile creates a random file with the provided seed and the
// provided size.
func CreateRandomFile(t *testing.T, rseed, size int) (path string) {
if size == 0 {
size = 1600
}
source := io.LimitReader(rand.New(rand.NewSource(int64(rseed))), int64(size))
file, err := os.CreateTemp(t.TempDir(), "sourcefile.dat")
require.NoError(t, err)
n, err := io.Copy(file, source)
require.NoError(t, err)
require.EqualValues(t, n, size)
return file.Name()
}
// CreateRandomFile creates a normal file with the provided seed and the
// provided size and then transforms it to a CARv1 file and returns it.
func CreateRandomCARv1(t *testing.T, rseed, size int, opts ...GeneratedDAGOpts) (carV1FilePath string, origFilePath string) {
ctx := context.Background()
if size == 0 {
size = 1600
}
source := io.LimitReader(rand.New(rand.NewSource(int64(rseed))), int64(size))
file, err := os.CreateTemp(t.TempDir(), "sourcefile.dat")
require.NoError(t, err)
n, err := io.Copy(file, source)
require.NoError(t, err)
require.EqualValues(t, n, size)
//
_, err = file.Seek(0, io.SeekStart)
require.NoError(t, err)
bs := bstore.NewBlockstore(dssync.MutexWrap(ds.NewMapDatastore()))
dagSvc := merkledag.NewDAGService(blockservice.New(bs, offline.Exchange(bs)))
root := writeUnixfsDAG(ctx, t, file, dagSvc, opts...)
// create a CARv1 file from the DAG
tmp, err := os.CreateTemp(t.TempDir(), "randcarv1")
require.NoError(t, err)
require.NoError(t, car.WriteCar(ctx, dagSvc, []cid.Cid{root}, tmp))
_, err = tmp.Seek(0, io.SeekStart)
require.NoError(t, err)
hd, _, err := car.ReadHeader(bufio.NewReader(tmp))
require.NoError(t, err)
require.EqualValues(t, 1, hd.Version)
require.Len(t, hd.Roots, 1)
require.NoError(t, tmp.Close())
return tmp.Name(), file.Name()
}
type GeneratedDAGOpts struct {
ChunkSize int64
Maxlinks int
}
func writeUnixfsDAG(ctx context.Context, t *testing.T, rd io.Reader, dag ipldformat.DAGService, opts ...GeneratedDAGOpts) cid.Cid {
dagOpts := GeneratedDAGOpts{
ChunkSize: unixfsChunkSize,
Maxlinks: 1024,
}
if len(opts) > 0 {
dagOpts = opts[0]
}
rpf := files.NewReaderFile(rd)
// generate the dag and get the root
// import to UnixFS
prefix, err := merkledag.PrefixForCidVersion(1)
require.NoError(t, err)
prefix.MhType = defaultHashFunction
bufferedDS := ipldformat.NewBufferedDAG(ctx, dag)
params := ihelper.DagBuilderParams{
Maxlinks: dagOpts.Maxlinks,
RawLeaves: true,
CidBuilder: cidutil.InlineBuilder{
Builder: prefix,
Limit: 126,
},
Dagserv: bufferedDS,
}
db, err := params.New(chunk.NewSizeSplitter(rpf, dagOpts.ChunkSize))
require.NoError(t, err)
nd, err := balanced.Layout(db)
require.NoError(t, err)
require.NotEqualValues(t, cid.Undef, nd.Cid())
err = bufferedDS.Commit()
require.NoError(t, err)
require.NoError(t, rpf.Close())
return nd.Cid()
}
// AssertFilesEqual compares two files by blake2b hash equality and
// fails the test if unequal.
func AssertFilesEqual(t *testing.T, left, right string) {
// initialize hashes.
leftH, rightH := blake2b.New256(), blake2b.New256()
// open files.
leftF, err := os.Open(left)
require.NoError(t, err)
rightF, err := os.Open(right)
require.NoError(t, err)
// feed hash functions.
_, err = io.Copy(leftH, leftF)
require.NoError(t, err)
_, err = io.Copy(rightH, rightF)
require.NoError(t, err)
// compute digests.
leftD, rightD := leftH.Sum(nil), rightH.Sum(nil)
require.True(t, bytes.Equal(leftD, rightD))
}