Keep the metadata.favorite for shared io.cozy.files (#4489)

model/sharing/files.go

@@ -1404,7 +1404,10 @@ func fileToJSONDoc(file *vfs.FileDoc, instanceURL string) couchdb.JSONDoc {
 		doc.M["restore_path"] = file.RestorePath
 	}
 	if len(file.Metadata) > 0 {
-		doc.M["metadata"] = file.Metadata.RemoveCertifiedMetadata()
+		meta := file.Metadata
+		meta = meta.RemoveCertifiedMetadata()
+		meta = meta.RemoveFavoriteMetadata()
+		doc.M["metadata"] = meta
 	}
 	fcm := file.CozyMetadata
 	if fcm == nil {

model/vfs/metadata.go

@@ -60,6 +60,23 @@ func MergeMetadata(doc *FileDoc, meta Metadata) {
 	}
 }
 
+// RemoveFavoriteMetadata returns a metadata map where the favorite key has been
+// removed. It can be useful for sharing, as favorite metadata are only valid
+// localy.
+func (m Metadata) RemoveFavoriteMetadata() Metadata {
+	if len(m) == 0 {
+		return Metadata{}
+	}
+	result := make(Metadata, len(m))
+	for k, v := range m {
+		if k == consts.FavoriteKey {
+			continue
+		}
+		result[k] = v
+	}
+	return result
+}
+
 // RemoveCertifiedMetadata returns a metadata map where the keys that are
 // certified have been removed. It can be useful for sharing, as certified
 // metadata are only valid localy.

pkg/consts/file.go

@@ -35,6 +35,8 @@ const (
 	CarbonCopyKey = "carbonCopy"
 	// ElectronicSafeKey is the metadata key for an electronic safe (certified)
 	ElectronicSafeKey = "electronicSafe"
+	// FavoriteKey is the metadata key for a favorite.
+	FavoriteKey = "favorite"
 )
 
 const (