tokens: expose Inspect and FindTag

tokens/inspect.go

@@ -1,90 +1,19 @@
 package tokens
 
-//
+import (
-// // EnvelopeInfo describes the fields of an Envelope enclosing a UCAN token.
+	"github.com/ipld/go-ipld-prime/datamodel"
-// type EnvelopeInfo struct {
+
-// 	Signature    []byte
+	"github.com/ucan-wg/go-ucan/tokens/internal/envelope"
-// 	Tag          string
+)
-// 	VarsigHeader []byte
+
-// }
+type Info = envelope.Info
-//
+
-// // InspectEnvelope accepts arbitrary data and attempts to decode it as a
+// Inspect inspects the given token IPLD representation and extract some envelope facts.
-// // UCAN token's Envelope.
+func Inspect(node datamodel.Node) (Info, error) {
-// func Inspect(data []byte) (EnvelopeInfo, error) {
+	return envelope.Inspect(node)
-// 	undef := EnvelopeInfo{}
+}
-//
+
-// 	node, err := decodeAny(data)
+// FindTag inspect the given token IPLD representation and extract the token tag.
-// 	if err != nil {
+func FindTag(node datamodel.Node) (string, error) {
-// 		return undef, err
+	return envelope.FindTag(node)
-// 	}
+}
-//
-// 	info, err := envelope.inspect(node)
-// 	if err != nil {
-// 		return undef, err
-// 	}
-//
-// 	iterator := info.SigPayloadNode.MapIterator()
-// 	foundVarsigHeader := false
-// 	foundTokenPayload := false
-// 	tag := ""
-// 	i := 0
-//
-// 	for !iterator.Done() {
-// 		k, _, err := iterator.Next()
-// 		if err != nil {
-// 			return undef, err
-// 		}
-//
-// 		key, err := k.AsString()
-// 		if err != nil {
-// 			return undef, err
-// 		}
-//
-// 		if key == envelope.VarsigHeaderKey {
-// 			foundVarsigHeader = true
-// 			i++
-//
-// 			continue
-// 		}
-//
-// 		if strings.HasPrefix(key, envelope.UCANTagPrefix) {
-// 			tag = key
-// 			foundTokenPayload = true
-// 			i++
-// 		}
-// 	}
-//
-// 	if i != 2 {
-// 		return undef, fmt.Errorf("expected two and only two fields in SigPayload: %d", i)
-// 	}
-//
-// 	if !foundVarsigHeader {
-// 		return undef, errors.New("failed to find VarsigHeader field")
-// 	}
-//
-// 	if !foundTokenPayload {
-// 		return undef, errors.New("failed to find TokenPayload field")
-// 	}
-//
-// 	return EnvelopeInfo{
-// 		Signature:    info.Signature,
-// 		Tag:          tag,
-// 		VarsigHeader: info.VarsigHeader,
-// 	}, nil
-// }
-//
-// func decodeAny(data []byte) (datamodel.Node, error) {
-// 	for _, decoder := range []codec.Decoder{
-// 		dagcbor.Decode,
-// 		dagjson.Decode,
-// 		cbor.Decode,
-// 		json.Decode,
-// 		raw.Decode,
-// 	} {
-// 		if node, err := ipld.Decode(data, decoder); err == nil {
-// 			return node, nil
-// 		}
-// 	}
-//
-// 	return nil, errors.New("failed to decode (any) the provided data")
-// }

tokens/inspect_test.go

@@ -1,24 +0,0 @@
-package tokens_test
-
-// func TestInspect(t *testing.T) {
-// 	t.Parallel()
-//
-// 	for _, filename := range []string{
-// 		"example.dagcbor",
-// 		"example.dagjson",
-// 	} {
-// 		t.Run(filename, func(t *testing.T) {
-// 			t.Parallel()
-//
-// 			data := golden.Get(t, filename)
-// 			expSig, err := base64.RawStdEncoding.DecodeString("fPqfwL3iFpbw9SvBiq0DIbUurv9o6c36R08tC/yslGrJcwV51ghzWahxdetpEf6T5LCszXX9I/K8khvnmAxjAg")
-// 			require.NoError(t, err)
-//
-// 			info, err := tokens.Inspect(data)
-// 			require.NoError(t, err)
-// 			assert.Equal(t, expSig, info.Signature)
-// 			assert.Equal(t, "ucan/example@v1.0.0-rc.1", info.Tag)
-// 			assert.Equal(t, []byte{0x34, 0xed, 0x1, 0x71}, info.VarsigHeader)
-// 		})
-// 	}
-// }

tokens/internal/envelope/ipld.go

@@ -131,15 +131,10 @@ func FromIPLD[T Tokener](node datamodel.Node) (T, error) {
 		return zero, errors.New("data doesn't match the expected type")
 	}
 
-	tokenPayloadNode, err := info.sigPayloadNode.LookupByString(info.Tag)
-	if err != nil {
-		return zero, err
-	}
-
 	// This needs to be done before converting this node to its schema
 	// representation (afterwards, the field might be renamed os it's safer
 	// to use the wire name).
-	issuerNode, err := tokenPayloadNode.LookupByString("iss")
+	issuerNode, err := info.tokenPayloadNode.LookupByString("iss")
 	if err != nil {
 		return zero, err
 	}
@@ -149,12 +144,12 @@ func FromIPLD[T Tokener](node datamodel.Node) (T, error) {
 	// unwrapping it.
 	nb := zero.Prototype().Representation().NewBuilder()
 
-	err = nb.AssignNode(tokenPayloadNode)
+	err = nb.AssignNode(info.tokenPayloadNode)
 	if err != nil {
 		return zero, err
 	}
 
-	tokenPayloadNode = nb.Build()
+	tokenPayloadNode := nb.Build()
 
 	tokenPayload := bindnode.Unwrap(tokenPayloadNode)
 	if tokenPayload == nil {
@@ -279,13 +274,17 @@ func ToIPLD(privKey crypto.PrivKey, token Tokener) (datamodel.Node, error) {
 	})
 }
 
-// FindTag inspect the given token IPLD representation and extract the token tag.
+// FindTag inspects the given token IPLD representation and extract the token tag.
 func FindTag(node datamodel.Node) (string, error) {
 	sigPayloadNode, err := node.LookupByIndex(1)
 	if err != nil {
 		return "", err
 	}
 
+	if sigPayloadNode.Kind() != datamodel.Kind_Map {
+		return "", fmt.Errorf("unexpected type instead of map")
+	}
+
 	it := sigPayloadNode.MapIterator()
 	i := 0
 
@@ -313,12 +312,14 @@ func FindTag(node datamodel.Node) (string, error) {
 }
 
 type Info struct {
-	Tag            string
+	Tag              string
-	Signature      []byte
+	Signature        []byte
-	sigPayloadNode datamodel.Node // private, we don't want to expose that
+	VarsigHeader     []byte
-	VarsigHeader   []byte
+	sigPayloadNode   datamodel.Node // private, we don't want to expose that
+	tokenPayloadNode datamodel.Node // private, we don't want to expose that
 }
 
+// Inspect inspects the given token IPLD representation and extract some envelope facts.
 func Inspect(node datamodel.Node) (Info, error) {
 	var res Info
 
@@ -337,6 +338,10 @@ func Inspect(node datamodel.Node) (Info, error) {
 		return Info{}, err
 	}
 
+	if res.sigPayloadNode.Kind() != datamodel.Kind_Map {
+		return Info{}, fmt.Errorf("unexpected type instead of map")
+	}
+
 	it := res.sigPayloadNode.MapIterator()
 	foundVarsigHeader := false
 	foundTokenPayload := false
@@ -368,6 +373,7 @@ func Inspect(node datamodel.Node) (Info, error) {
 		case strings.HasPrefix(key, UCANTagPrefix):
 			foundTokenPayload = true
 			res.Tag = key
+			res.tokenPayloadNode = v
 		default:
 			return Info{}, fmt.Errorf("unexpected key type %q", key)
 		}

tokens/internal/envelope/ipld_test.go

@@ -3,12 +3,16 @@ package envelope_test
 import (
 	"bytes"
 	"crypto/sha256"
+	"encoding/base64"
 	"testing"
 
+	"github.com/ipld/go-ipld-prime"
+	"github.com/ipld/go-ipld-prime/codec/dagcbor"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	"github.com/ucan-wg/go-ucan/tokens/internal/envelope"
 	"gotest.tools/v3/golden"
+
+	"github.com/ucan-wg/go-ucan/tokens/internal/envelope"
 )
 
 func TestDecode(t *testing.T) {
@@ -149,3 +153,20 @@ func TestHash(t *testing.T) {
 	require.Equal(t, hash1[:], hash2)
 	require.Equal(t, hash1[:], hash3)
 }
+
+func TestInspect(t *testing.T) {
+	t.Parallel()
+
+	data := golden.Get(t, "example.dagcbor")
+	node, err := ipld.Decode(data, dagcbor.Decode)
+	require.NoError(t, err)
+
+	expSig, err := base64.RawStdEncoding.DecodeString("fPqfwL3iFpbw9SvBiq0DIbUurv9o6c36R08tC/yslGrJcwV51ghzWahxdetpEf6T5LCszXX9I/K8khvnmAxjAg")
+	require.NoError(t, err)
+
+	info, err := envelope.Inspect(node)
+	require.NoError(t, err)
+	assert.Equal(t, expSig, info.Signature)
+	assert.Equal(t, "ucan/example@v1.0.0-rc.1", info.Tag)
+	assert.Equal(t, []byte{0x34, 0xed, 0x1, 0x71}, info.VarsigHeader)
+}