WIP

Signed-off-by: Leonard Lyubich <leonard@morphbits.io>

contracts/contracts.go

@@ -0,0 +1,122 @@
+package contracts
+
+import (
+	"embed"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/fs"
+	"strconv"
+	"strings"
+
+	"github.com/nspcc-dev/neo-go/pkg/io"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/nef"
+)
+
+type Contract struct {
+	NEF      nef.File
+	Manifest manifest.Manifest
+}
+
+type Contracts struct {
+	NNS      Contract
+	Alphabet Contract
+	Others   []Contract
+}
+
+//go:embed *-contract.nef *-contract.manifest.json
+var _fs embed.FS
+
+func Get() (Contracts, error) {
+	return get(_fs)
+}
+
+const fileSuffixNEF = "-contract.nef"
+
+func get(_fs fs.FS) (Contracts, error) {
+	var res Contracts
+
+	const nnsPrefix = "nns"
+	err := readContractFromFilesWithPrefix(&res.NNS, _fs, nnsPrefix)
+	if err != nil {
+		return res, fmt.Errorf("read NNS contract: %w", err)
+	}
+
+	const alphabetPrefix = "alphabet"
+	err = readContractFromFilesWithPrefix(&res.Alphabet, _fs, alphabetPrefix)
+	if err != nil {
+		return res, fmt.Errorf("read Alphabet contract: %w", err)
+	}
+
+	nefFiles, err := fs.Glob(_fs, "*"+fileSuffixNEF)
+	if err != nil {
+		return res, fmt.Errorf("match files with suffix %s", fileSuffixNEF)
+	}
+
+	mOrdered := make(map[int]Contract, len(nefFiles))
+
+	for i := range nefFiles {
+		prefix := strings.TrimSuffix(nefFiles[i], fileSuffixNEF)
+		if prefix == nnsPrefix || prefix == alphabetPrefix {
+			continue
+		}
+
+		index, err := strconv.Atoi(prefix)
+		if err != nil {
+			return res, fmt.Errorf("invalid prefix of file '%s', expected index number", nefFiles[i])
+		}
+
+		var c Contract
+
+		err = readContractFromFilesWithPrefix(&c, _fs, prefix)
+		if err != nil {
+			return res, fmt.Errorf("read contract #%d: %w", index, err)
+		}
+
+		mOrdered[index] = c
+	}
+
+	if len(mOrdered) == 0 {
+		return res, errors.New("missing indexed contracts")
+	}
+
+	res.Others = make([]Contract, len(mOrdered))
+	var ok bool
+
+	for i := range res.Others {
+		res.Others[i], ok = mOrdered[i]
+		if !ok {
+			return res, fmt.Errorf("missing index number %d", i)
+		}
+	}
+
+	return res, nil
+}
+
+func readContractFromFilesWithPrefix(c *Contract, _fs fs.FS, filePrefix string) error {
+	fNEF, err := _fs.Open(filePrefix + fileSuffixNEF)
+	if err != nil {
+		return fmt.Errorf("open file containing contract NEF: %w", err)
+	}
+	defer fNEF.Close()
+
+	fManifest, err := _fs.Open(filePrefix + "-contract.manifest.json")
+	if err != nil {
+		return fmt.Errorf("open file containing contract NEF: %w", err)
+	}
+	defer fManifest.Close()
+
+	bReader := io.NewBinReaderFromIO(fNEF)
+	c.NEF.DecodeBinary(bReader)
+	if bReader.Err != nil {
+		return fmt.Errorf("decode contract NEF from binary: %w", bReader.Err)
+	}
+
+	err = json.NewDecoder(fManifest).Decode(&c.Manifest)
+	if err != nil {
+		return fmt.Errorf("decode contract manifest from JSON")
+	}
+
+	return nil
+}

contracts/contracts_test.go

@@ -0,0 +1,124 @@
+package contracts
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/fs"
+	"testing"
+	"testing/fstest"
+
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/nef"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetDir(t *testing.T) {
+	cs, err := Get()
+	require.NoError(t, err)
+
+	// names are taken from neofs-contract repository
+	require.Equal(t, "NameService", cs.NNS.Manifest.Name)
+	require.Equal(t, "NeoFS Alphabet", cs.Alphabet.Manifest.Name)
+	require.Len(t, cs.Others, 2)
+	require.Equal(t, "NeoFS Audit", cs.Others[0].Manifest.Name)
+	require.Equal(t, "NeoFS Balance", cs.Others[1].Manifest.Name)
+}
+
+func TestGet(t *testing.T) {
+	_fs := fstest.MapFS{}
+
+	// missing or invalid NNS
+	_, err := get(_fs)
+	require.ErrorIs(t, err, fs.ErrNotExist)
+
+	setInvalidContractFiles(t, _fs, "nns")
+	_, err = get(_fs)
+	require.Error(t, err)
+
+	// add NNS
+	nnsContract := setValidContractFiles(t, _fs, "nns")
+
+	// missing or invalid Alphabet
+	_, err = get(_fs)
+	require.ErrorIs(t, err, fs.ErrNotExist)
+
+	setInvalidContractFiles(t, _fs, "alphabet")
+	_, err = get(_fs)
+	require.Error(t, err)
+
+	alphabetContract := setValidContractFiles(t, _fs, "alphabet")
+
+	// missing or invalid indexed contracts
+	_, err = get(_fs)
+	require.Error(t, err)
+
+	_fs["any-contract.nef"] = &fstest.MapFile{Data: []byte("any script")}
+
+	_, err = get(_fs)
+	require.Error(t, err)
+
+	delete(_fs, "any-contract.nef")
+
+	// add indexed contracts
+	setInvalidContractFiles(t, _fs, "0")
+	_, err = get(_fs)
+	require.Error(t, err)
+
+	firstContract := setValidContractFiles(t, _fs, "0")
+
+	_, err = get(_fs)
+	require.NoError(t, err)
+
+	// add hole
+	thirdContract := setValidContractFiles(t, _fs, "2")
+	_, err = get(_fs)
+	require.Error(t, err)
+
+	// fill hole
+	secondContract := setValidContractFiles(t, _fs, "1")
+	c, err := get(_fs)
+	require.NoError(t, err)
+
+	// check correctness
+	require.Equal(t, c.NNS, nnsContract)
+	require.Equal(t, c.Alphabet, alphabetContract)
+	require.Len(t, c.Others, 3)
+	require.Equal(t, c.Others[0], firstContract)
+	require.Equal(t, c.Others[1], secondContract)
+	require.Equal(t, c.Others[2], thirdContract)
+}
+
+func setValidContractFiles(tb testing.TB, _fs fstest.MapFS, prefix string) Contract {
+	_setContractFiles(tb, _fs, prefix, true)
+
+	var c Contract
+
+	err := readContractFromFilesWithPrefix(&c, _fs, prefix)
+	require.NoError(tb, err)
+
+	return c
+}
+
+func setInvalidContractFiles(tb testing.TB, _fs fstest.MapFS, prefix string) {
+	_setContractFiles(tb, _fs, prefix, false)
+}
+
+func _setContractFiles(tb testing.TB, _fs fstest.MapFS, prefix string, valid bool) {
+	var bNEF, jManifest []byte
+	if valid {
+		_nef, err := nef.NewFile([]byte(fmt.Sprintf("any %s script", prefix)))
+		require.NoError(tb, err)
+
+		bNEF, err = _nef.Bytes()
+		require.NoError(tb, err)
+
+		jManifest, err = json.Marshal(manifest.NewManifest(prefix + " contract"))
+		require.NoError(tb, err)
+	} else {
+		bNEF = []byte("invalid NEF")
+		jManifest = []byte("invalid manifest")
+	}
+
+	_fs[prefix+"-contract.nef"] = &fstest.MapFile{Data: bNEF}
+	_fs[prefix+"-contract.manifest.json"] = &fstest.MapFile{Data: jManifest}
+}