[bugfix] Extract description as summary first, fall back to name (#2303)

internal/ap/extract.go

@@ -600,12 +600,23 @@ func ExtractAttachment(i Attachmentable) (*gtsmodel.MediaAttachment, error) {
 
 	return &gtsmodel.MediaAttachment{
 		RemoteURL:   remoteURL.String(),
-		Description: ExtractName(i),
+		Description: ExtractDescription(i),
 		Blurhash:    ExtractBlurhash(i),
 		Processing:  gtsmodel.ProcessingStatusReceived,
 	}, nil
 }
 
+// ExtractDescription extracts the image description
+// of an attachmentable, if present. Will try the
+// 'summary' prop first, then fall back to 'name'.
+func ExtractDescription(i Attachmentable) string {
+	if summary := ExtractSummary(i); summary != "" {
+		return summary
+	}
+
+	return ExtractName(i)
+}
+
 // ExtractBlurhash extracts the blurhash string value
 // from the given WithBlurhash interface, or returns
 // an empty string if nothing is found.

internal/ap/extractattachments_test.go

@@ -18,6 +18,8 @@
 package ap_test
 
 import (
+	"context"
+	"encoding/json"
 	"testing"
 
 	"github.com/stretchr/testify/suite"
@@ -38,6 +40,43 @@ func (suite *ExtractAttachmentsTestSuite) TestExtractAttachmentMissingURL() {
 	suite.Nil(attachment)
 }
 
+func (suite *ExtractAttachmentsTestSuite) TestExtractDescription() {
+	// Note: normally a single attachment on a Note or
+	// similar wouldn't have the `@context` field set,
+	// but we set it here because we're parsing it as
+	// a discrete/standalone AP Object for this test.
+	attachmentableJSON := `{
+  "@context": "https://www.w3.org/ns/activitystreams",
+  "mediaType": "image/jpeg",
+  "name": "z64KTcw2h2bZ8s67k2.jpg",
+  "summary": "A very large panel that is entirely twist switches",
+  "type": "Document",
+  "url": "https://example.org/d/XzKw4M2Sc1pBxj3hY4.jpg"
+}`
+
+	raw := make(map[string]interface{})
+	if err := json.Unmarshal([]byte(attachmentableJSON), &raw); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	t, err := streams.ToType(context.Background(), raw)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	attachmentable, ok := t.(ap.Attachmentable)
+	if !ok {
+		suite.FailNow("type was not Attachmentable")
+	}
+
+	attachment, err := ap.ExtractAttachment(attachmentable)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	suite.Equal("A very large panel that is entirely twist switches", attachment.Description)
+}
+
 func TestExtractAttachmentsTestSuite(t *testing.T) {
 	suite.Run(t, &ExtractAttachmentsTestSuite{})
 }

internal/ap/interfaces.go

@@ -164,6 +164,7 @@ type Attachmentable interface {
 	WithMediaType
 	WithURL
 	WithName
+	WithSummary
 	WithBlurhash
 }