Support JSON-LD graph in document @context

did/document.go

@@ -51,7 +51,7 @@ func ParseDocument(raw string) (*Document, error) {
 
 // Document represents a DID Document as specified by the DID Core specification (https://www.w3.org/TR/did-core/).
 type Document struct {
-	Context              []ssi.URI                 `json:"@context"`
+	Context              []interface{}             `json:"@context"`
 	ID                   DID                       `json:"id"`
 	Controller           []DID                     `json:"controller,omitempty"`
 	AlsoKnownAs          []ssi.URI                 `json:"alsoKnownAs,omitempty"`

did/document_test.go

@@ -55,8 +55,8 @@ func Test_Document(t *testing.T) {
 			return
 		}
 		expected := "https://www.w3.org/ns/did/v1"
-		if expected != actual.Context[0].String() {
-			t.Errorf("expected:\n%s\n, got:\n%s", expected, actual.Context[0].String())
+		if expected != actual.Context[0].(string) {
+			t.Errorf("expected:\n%s\n, got:\n%s", expected, actual.Context[0].(string))
 		}
 	})
 	t.Run("validate controllers", func(t *testing.T) {

did/validator.go

@@ -3,6 +3,7 @@ package did
 import (
 	"errors"
 	"fmt"
+	ssi "github.com/nuts-foundation/go-did"
 	"strings"
 )
 
@@ -106,7 +107,7 @@ type baseValidator struct{}
 
 func (w baseValidator) Validate(document Document) error {
 	// Verify `@context`
-	if !containsContext(document, DIDContextV1) {
+	if !containsContextURI(document, DIDContextV1) {
 		return makeValidationError(ErrInvalidContext)
 	}
 	// Verify `id`
@@ -186,9 +187,20 @@ func (s serviceValidator) Validate(document Document) error {
 	return nil
 }
 
-func containsContext(document Document, ctx string) bool {
+func containsContextURI(document Document, ctx string) bool {
 	for _, curr := range document.Context {
-		if curr.String() == ctx {
+		var currStr string
+		var ok bool
+		if currStr, ok = curr.(string); !ok {
+			// or it might be ssi.URI
+			if currURI, ok := curr.(ssi.URI); ok {
+				currStr = currURI.String()
+			} else {
+				// can't compare this context entry (might be a JSON-LD graph)
+				continue
+			}
+		}
+		if currStr == ctx {
 			return true
 		}
 	}

did/validator_test.go

@@ -21,7 +21,12 @@ func TestW3CSpecValidator(t *testing.T) {
 		}
 		t.Run("context is missing DIDv1", func(t *testing.T) {
 			input := document()
-			input.Context = []ssi.URI{}
+			input.Context = []interface{}{
+				"someting-else",
+				map[string]interface{}{
+					"@base": "did:example:123",
+				},
+			}
 			assertIsError(t, ErrInvalidContext, W3CSpecValidator{}.Validate(input))
 		})
 		t.Run("invalid ID - is empty", func(t *testing.T) {
@@ -169,7 +174,12 @@ func document() Document {
 	serviceID := *did
 	serviceID.Fragment = "service-1"
 	doc := Document{
-		Context:            []ssi.URI{DIDContextV1URI()},
+		Context: []interface{}{
+			DIDContextV1URI(),
+			map[string]interface{}{
+				"@base": "did:example:12345",
+			},
+		},
 		ID:                 *did,
 		Controller:         []DID{*did},
 		VerificationMethod: []*VerificationMethod{vm},