[MM-59519] preserve DM/GM unread/read state over export and import (#27707)

server/channels/app/export_converters.go

@@ -40,17 +40,17 @@ func ImportLineFromChannel(channel *model.ChannelForExport) *imports.LineImportD
 	}
 }
 
-func ImportLineFromDirectChannel(channel *model.DirectChannelForExport, favoritedBy []string) *imports.LineImportData {
-	channelMembers := *channel.Members
+func ImportLineFromDirectChannel(channel *model.DirectChannelForExport, favoritedBy, shownBy []string) *imports.LineImportData {
+	channelMembers := channel.Members
 	if len(channelMembers) == 1 {
-		channelMembers = []string{channelMembers[0], channelMembers[0]}
+		channelMembers = []*model.ChannelMemberForExport{channelMembers[0], channelMembers[0]}
 	}
 
 	line := &imports.LineImportData{
 		Type: "direct_channel",
 		DirectChannel: &imports.DirectChannelImportData{
-			Header:  &channel.Header,
-			Members: &channelMembers,
+			Header:       &channel.Header,
+			Participants: importDirectChannelMembersFromChannelMembers(channelMembers),
 		},
 	}
 
@@ -58,9 +58,82 @@ func ImportLineFromDirectChannel(channel *model.DirectChannelForExport, favorite
 		line.DirectChannel.FavoritedBy = &favoritedBy
 	}
 
+	if len(shownBy) != 0 {
+		line.DirectChannel.ShownBy = &shownBy
+	}
+
 	return line
 }
 
+func importDirectChannelMembersFromChannelMembers(members []*model.ChannelMemberForExport) []*imports.DirectChannelMemberImportData {
+	importedMembers := make([]*imports.DirectChannelMemberImportData, len(members))
+	for i, member := range members {
+		props := member.NotifyProps
+		notifyProps := imports.UserChannelNotifyPropsImportData{}
+
+		desktop, exist := props[model.DesktopNotifyProp]
+		if exist {
+			notifyProps.Desktop = &desktop
+		}
+		mobile, exist := props[model.PushNotifyProp]
+		if exist {
+			notifyProps.Mobile = &mobile
+		}
+		email, exist := props[model.EmailNotifyProp]
+		if exist {
+			notifyProps.Email = &email
+		}
+		ignoreMentions, exist := props[model.IgnoreChannelMentionsNotifyProp]
+		if exist {
+			notifyProps.IgnoreChannelMentions = &ignoreMentions
+		}
+		channelAutoFallow, exist := props[model.ChannelAutoFollowThreads]
+		if exist {
+			notifyProps.ChannelAutoFollowThreads = &channelAutoFallow
+		}
+		markUnread, exist := props[model.MarkUnreadNotifyProp]
+		if exist {
+			notifyProps.MarkUnread = &markUnread
+		}
+
+		dcm := &imports.DirectChannelMemberImportData{
+			Username:    &member.Username,
+			NotifyProps: &notifyProps,
+		}
+
+		if member.SchemeUser {
+			dcm.SchemeUser = &member.SchemeUser
+		}
+		if member.SchemeAdmin {
+			dcm.SchemeAdmin = &member.SchemeAdmin
+		}
+		if member.SchemeGuest {
+			dcm.SchemeGuest = &member.SchemeGuest
+		}
+		if member.LastViewedAt != 0 {
+			dcm.LastViewedAt = &member.LastViewedAt
+		}
+		if member.MentionCount != 0 {
+			dcm.MentionCount = &member.MentionCount
+		}
+		if member.MentionCountRoot != 0 {
+			dcm.MentionCountRoot = &member.MentionCountRoot
+		}
+		if member.MsgCount != 0 {
+			dcm.MsgCount = &member.MsgCount
+		}
+		if member.MsgCountRoot != 0 {
+			dcm.MsgCountRoot = &member.MsgCountRoot
+		}
+		if member.UrgentMentionCount != 0 {
+			dcm.UrgentMentionCount = &member.UrgentMentionCount
+		}
+
+		importedMembers[i] = dcm
+	}
+	return importedMembers
+}
+
 func ImportLineFromUser(user *model.User, exportedPrefs map[string]*string) *imports.LineImportData {
 	// Bulk Importer doesn't accept "empty string" for AuthService.
 	var authService *string