refactor: Moved generic utility functions out of DIDExchange

pkg/didcomm/common/service/destination.go

@@ -0,0 +1,57 @@
+/*
+Copyright SecureKey Technologies Inc. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package service
+
+import (
+	"fmt"
+
+	diddoc "github.com/hyperledger/aries-framework-go/pkg/doc/did"
+	"github.com/hyperledger/aries-framework-go/pkg/framework/aries/api/vdri"
+)
+
+// Destination provides the recipientKeys, routingKeys, and serviceEndpoint for an outbound message.
+// Can be populated from an Invitation or DIDDoc.
+type Destination struct {
+	RecipientKeys        []string
+	ServiceEndpoint      string
+	RoutingKeys          []string
+	TransportReturnRoute string
+}
+
+const (
+	didCommServiceType = "did-communication"
+	ed25519KeyType     = "Ed25519VerificationKey2018"
+)
+
+// GetDestination constructs a Destination struct based on the given DID and parameters
+// It resolves the DID using the given VDR, and collects relevant data from the resolved DIDDoc.
+func GetDestination(did string, vdr vdri.Registry) (*Destination, error) {
+	didDoc, err := vdr.Resolve(did)
+	if err != nil {
+		return nil, err
+	}
+
+	return CreateDestination(didDoc)
+}
+
+// CreateDestination makes a DIDComm Destination object from a DID Doc
+func CreateDestination(didDoc *diddoc.Doc) (*Destination, error) {
+	didCommService, ok := diddoc.LookupService(didDoc, didCommServiceType)
+	if !ok {
+		return nil, fmt.Errorf("create destination: missing DID doc service")
+	}
+
+	recipientKeys, ok := diddoc.LookupRecipientKeys(didDoc, didCommServiceType, ed25519KeyType)
+	if !ok {
+		return nil, fmt.Errorf("create destination: missing keys")
+	}
+
+	return &Destination{
+		RecipientKeys:   recipientKeys,
+		ServiceEndpoint: didCommService.ServiceEndpoint,
+	}, nil
+}

pkg/didcomm/common/service/destination_test.go

@@ -0,0 +1,143 @@
+/*
+Copyright SecureKey Technologies Inc. All Rights Reserved.
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package service
+
+import (
+	"crypto/ed25519"
+	"crypto/rand"
+	"errors"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/btcsuite/btcutil/base58"
+	"github.com/stretchr/testify/require"
+
+	"github.com/hyperledger/aries-framework-go/pkg/doc/did"
+	mockdiddoc "github.com/hyperledger/aries-framework-go/pkg/internal/mock/diddoc"
+	mockvdri "github.com/hyperledger/aries-framework-go/pkg/internal/mock/vdri"
+)
+
+func TestGetDestinationFromDID(t *testing.T) {
+	doc := createDIDDoc()
+
+	t.Run("successfully getting destination from public DID", func(t *testing.T) {
+		vdr := mockvdri.MockVDRIRegistry{ResolveValue: doc}
+		destination, err := GetDestination(doc.ID, &vdr)
+		require.NoError(t, err)
+		require.NotNil(t, destination)
+	})
+
+	t.Run("test public key not found", func(t *testing.T) {
+		doc.PublicKey = nil
+		vdr := mockvdri.MockVDRIRegistry{ResolveValue: doc}
+		destination, err := GetDestination(doc.ID, &vdr)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "missing keys")
+		require.Nil(t, destination)
+	})
+
+	t.Run("test service not found", func(t *testing.T) {
+		doc2 := createDIDDoc()
+		doc2.Service = nil
+		vdr := mockvdri.MockVDRIRegistry{ResolveValue: doc2}
+		destination, err := GetDestination(doc2.ID, &vdr)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "missing DID doc service")
+		require.Nil(t, destination)
+	})
+
+	t.Run("test did document not found", func(t *testing.T) {
+		vdr := mockvdri.MockVDRIRegistry{ResolveErr: errors.New("resolver error")}
+		destination, err := GetDestination(doc.ID, &vdr)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "resolver error")
+		require.Nil(t, destination)
+	})
+}
+
+func TestPrepareDestination(t *testing.T) {
+	ed25519KeyType := "Ed25519VerificationKey2018"
+	didCommServiceType := "did-communication"
+
+	t.Run("successfully prepared destination", func(t *testing.T) {
+		dest, err := CreateDestination(mockdiddoc.GetMockDIDDoc())
+		require.NoError(t, err)
+		require.NotNil(t, dest)
+		require.Equal(t, dest.ServiceEndpoint, "https://localhost:8090")
+	})
+
+	t.Run("error while getting service", func(t *testing.T) {
+		didDoc := mockdiddoc.GetMockDIDDoc()
+		didDoc.Service = nil
+
+		dest, err := CreateDestination(didDoc)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "missing DID doc service")
+		require.Nil(t, dest)
+	})
+
+	t.Run("error while getting recipient keys from did doc", func(t *testing.T) {
+		didDoc := mockdiddoc.GetMockDIDDoc()
+		didDoc.Service[0].RecipientKeys = []string{}
+
+		recipientKeys, ok := did.LookupRecipientKeys(didDoc, didCommServiceType, ed25519KeyType)
+		require.False(t, ok)
+		require.Nil(t, recipientKeys)
+	})
+}
+
+func createDIDDoc() *did.Doc {
+	pubKey, _ := generateKeyPair()
+	return createDIDDocWithKey(pubKey)
+}
+
+func generateKeyPair() (string, []byte) {
+	pubKey, privKey, err := ed25519.GenerateKey(rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+
+	return base58.Encode(pubKey[:]), privKey
+}
+
+func createDIDDocWithKey(pub string) *did.Doc {
+	const (
+		didFormat    = "did:%s:%s"
+		didPKID      = "%s#keys-%d"
+		didServiceID = "%s#endpoint-%d"
+		method       = "test"
+	)
+
+	id := fmt.Sprintf(didFormat, method, pub[:16])
+	pubKeyID := fmt.Sprintf(didPKID, id, 1)
+	pubKey := did.PublicKey{
+		ID:         pubKeyID,
+		Type:       "Ed25519VerificationKey2018",
+		Controller: id,
+		Value:      []byte(pub),
+	}
+	services := []did.Service{
+		{
+			ID:              fmt.Sprintf(didServiceID, id, 1),
+			Type:            "did-communication",
+			ServiceEndpoint: "http://localhost:58416",
+			Priority:        0,
+			RecipientKeys:   []string{pubKeyID},
+		},
+	}
+	createdTime := time.Now()
+	didDoc := &did.Doc{
+		Context:   []string{did.Context},
+		ID:        id,
+		PublicKey: []did.PublicKey{pubKey},
+		Service:   services,
+		Created:   &createdTime,
+		Updated:   &createdTime,
+	}
+
+	return didDoc
+}

pkg/didcomm/common/service/service.go

@@ -107,11 +107,3 @@ func (m *DIDCommMsg) ThreadID() (string, error) {
 
 	return "", ErrThreadIDNotFound
 }
-
-// Destination provides the recipientKeys, routingKeys, and serviceEndpoint populated from Invitation
-type Destination struct {
-	RecipientKeys        []string
-	ServiceEndpoint      string
-	RoutingKeys          []string
-	TransportReturnRoute string
-}

pkg/didcomm/protocol/didexchange/service.go

@@ -636,7 +636,12 @@ func (s *Service) CreateImplicitInvitation(inviterLabel, inviterDID, inviteeLabe
 		return "", fmt.Errorf("resolve public did[%s]: %w", inviterDID, err)
 	}
 
-	dest, err := prepareDestination(didDoc)
+	// TODO: hardcoded key type
+	dest, err := service.CreateDestination(didDoc)
+	if err != nil {
+		return "", err
+	}
+
 	thID := generateRandomID()
 	connRecord := &ConnectionRecord{
 		ConnectionID:    generateRandomID(),