diff --git a/binding/format/protobuf/v2/protobuf.go b/binding/format/protobuf/v2/protobuf.go
index 2e76773e..4b8c2544 100644
--- a/binding/format/protobuf/v2/protobuf.go
+++ b/binding/format/protobuf/v2/protobuf.go
@@ -91,7 +91,7 @@ func ToProto(e *event.Event) (*pb.CloudEvent, error) {
 		dataSchemaStr := e.DataSchema()
 		uri, err := url.Parse(dataSchemaStr)
 		if err != nil {
-			return nil, fmt.Errorf("failed to url.Parse %s: %s", dataSchemaStr, err)
+			return nil, fmt.Errorf("failed to url.Parse %s: %w", dataSchemaStr, err)
 		}
 		container.Attributes[dataschema], _ = attributeFor(uri)
 	}
diff --git a/binding/format/protobuf/v2/protobuf_test.go b/binding/format/protobuf/v2/protobuf_test.go
index 0c7dbf87..3099bc4a 100644
--- a/binding/format/protobuf/v2/protobuf_test.go
+++ b/binding/format/protobuf/v2/protobuf_test.go
@@ -109,7 +109,7 @@ func TestFromProto(t *testing.T) {
 			Type:        "some.type",
 			Attributes: map[string]*pb.CloudEventAttributeValue{
 				"datacontenttype": {Attr: &pb.CloudEventAttributeValue_CeString{CeString: "application/json"}},
-				"dataschema":      {Attr: &pb.CloudEventAttributeValue_CeUri{CeUri: "link"}},
+				"dataschema":      {Attr: &pb.CloudEventAttributeValue_CeUri{CeUri: "https://example-data-schema.com"}},
 				"extra1":          {Attr: &pb.CloudEventAttributeValue_CeString{CeString: "extra1 value"}},
 				"extra2":          {Attr: &pb.CloudEventAttributeValue_CeInteger{CeInteger: 2}},
 				"extra3":          {Attr: &pb.CloudEventAttributeValue_CeBoolean{CeBoolean: true}},
@@ -125,7 +125,7 @@ func TestFromProto(t *testing.T) {
 			out.SetSource("/source")
 			out.SetType("some.type")
 			_ = out.SetData("application/json", map[string]interface{}{"unit": "test"})
-			out.SetDataSchema("link")
+			out.SetDataSchema("https://example-data-schema.com")
 			out.SetExtension("extra1", "extra1 value")
 			out.SetExtension("extra2", 2)
 			out.SetExtension("extra3", true)
@@ -142,7 +142,7 @@ func TestFromProto(t *testing.T) {
 			Type:        "some.type",
 			Attributes: map[string]*pb.CloudEventAttributeValue{
 				"datacontenttype": {Attr: &pb.CloudEventAttributeValue_CeString{CeString: "text/plain"}},
-				"dataschema":      {Attr: &pb.CloudEventAttributeValue_CeUri{CeUri: "link"}},
+				"dataschema":      {Attr: &pb.CloudEventAttributeValue_CeUri{CeUri: "https://example-data-schema.com"}},
 				"extra1":          {Attr: &pb.CloudEventAttributeValue_CeString{CeString: "extra1 value"}},
 				"extra2":          {Attr: &pb.CloudEventAttributeValue_CeInteger{CeInteger: 2}},
 				"extra3":          {Attr: &pb.CloudEventAttributeValue_CeBoolean{CeBoolean: true}},
@@ -158,7 +158,7 @@ func TestFromProto(t *testing.T) {
 			out.SetSource("/source")
 			out.SetType("some.type")
 			_ = out.SetData("text/plain", `this is some text with a "quote"`)
-			out.SetDataSchema("link")
+			out.SetDataSchema("https://example-data-schema.com")
 			out.SetExtension("extra1", "extra1 value")
 			out.SetExtension("extra2", 2)
 			out.SetExtension("extra3", true)
@@ -175,7 +175,7 @@ func TestFromProto(t *testing.T) {
 			Type:        "some.type",
 			Attributes: map[string]*pb.CloudEventAttributeValue{
 				"datacontenttype": {Attr: &pb.CloudEventAttributeValue_CeString{CeString: "application/json"}},
-				"dataschema":      {Attr: &pb.CloudEventAttributeValue_CeUri{CeUri: "link"}},
+				"dataschema":      {Attr: &pb.CloudEventAttributeValue_CeUri{CeUri: "https://example-data-schema.com"}},
 				"extra1":          {Attr: &pb.CloudEventAttributeValue_CeString{CeString: "extra1 value"}},
 				"extra2":          {Attr: &pb.CloudEventAttributeValue_CeInteger{CeInteger: 2}},
 				"extra3":          {Attr: &pb.CloudEventAttributeValue_CeBoolean{CeBoolean: true}},
@@ -191,7 +191,7 @@ func TestFromProto(t *testing.T) {
 			out.SetSource("/source")
 			out.SetType("some.type")
 			_ = out.SetData("application/json", `{"unit":"test"}`)
-			out.SetDataSchema("link")
+			out.SetDataSchema("https://example-data-schema.com")
 			out.SetExtension("extra1", "extra1 value")
 			out.SetExtension("extra2", 2)
 			out.SetExtension("extra3", true)