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

server/channels/app/imports/import_types.go

@@ -123,10 +123,27 @@ type UserChannelImportData struct {
 	LastViewedAt       *int64                            `json:"last_viewed_at,omitempty"`
 }
 
+type DirectChannelMemberImportData struct {
+	Username           *string                           `json:"username"`
+	NotifyProps        *UserChannelNotifyPropsImportData `json:"notify_props,omitempty"`
+	SchemeUser         *bool                             `json:"scheme_user,omitempty"`
+	SchemeAdmin        *bool                             `json:"scheme_admin,omitempty"`
+	SchemeGuest        *bool                             `json:"scheme_guest,omitempty"`
+	MentionCount       *int64                            `json:"mention_count,omitempty"`
+	MentionCountRoot   *int64                            `json:"mention_count_root,omitempty"`
+	UrgentMentionCount *int64                            `json:"urgend_mention_count,omitempty"`
+	MsgCount           *int64                            `json:"msg_count,omitempty"`
+	MsgCountRoot       *int64                            `json:"msg_count_root,omitempty"`
+	LastViewedAt       *int64                            `json:"last_viewed_at,omitempty"`
+}
+
 type UserChannelNotifyPropsImportData struct {
-	Desktop    *string `json:"desktop"`
-	Mobile     *string `json:"mobile"`
-	MarkUnread *string `json:"mark_unread"`
+	Desktop                  *string `json:"desktop"`
+	Mobile                   *string `json:"mobile"`
+	MarkUnread               *string `json:"mark_unread"`
+	Email                    *string `json:"email,omitempty"`
+	IgnoreChannelMentions    *string `json:"ignore_channel_mentions,omitempty"`
+	ChannelAutoFollowThreads *string `json:"channel_auto_follow_threads,omitempty"`
 }
 
 type EmojiImportData struct {
@@ -173,8 +190,10 @@ type PostImportData struct {
 }
 
 type DirectChannelImportData struct {
-	Members     *[]string `json:"members"`
-	FavoritedBy *[]string `json:"favorited_by"`
+	Members      *[]string                        `json:"members,omitempty"`
+	Participants []*DirectChannelMemberImportData `json:"participants,omitempty"`
+	FavoritedBy  *[]string                        `json:"favorited_by,omitempty"`
+	ShownBy      *[]string                        `json:"shown_by,omitempty"`
 
 	Header *string `json:"header"`
 }

server/channels/app/imports/import_validators.go

@@ -489,11 +489,19 @@ func ValidatePostImportData(data *PostImportData, maxPostSize int) *model.AppErr
 }
 
 func ValidateDirectChannelImportData(data *DirectChannelImportData) *model.AppError {
-	if data.Members == nil {
+	if data.Participants == nil && data.Members == nil {
 		return model.NewAppError("BulkImport", "app.import.validate_direct_channel_import_data.members_required.error", nil, "", http.StatusBadRequest)
 	}
 
-	if len(*data.Members) != 2 {
+	if data.Participants != nil && len(data.Participants) != 2 {
+		if len(data.Participants) < model.ChannelGroupMinUsers {
+			return model.NewAppError("BulkImport", "app.import.validate_direct_channel_import_data.members_too_few.error", nil, "", http.StatusBadRequest)
+		} else if len(data.Participants) > model.ChannelGroupMaxUsers {
+			return model.NewAppError("BulkImport", "app.import.validate_direct_channel_import_data.members_too_many.error", nil, "", http.StatusBadRequest)
+		}
+	}
+
+	if data.Members != nil && len(*data.Members) != 2 {
 		if len(*data.Members) < model.ChannelGroupMinUsers {
 			return model.NewAppError("BulkImport", "app.import.validate_direct_channel_import_data.members_too_few.error", nil, "", http.StatusBadRequest)
 		} else if len(*data.Members) > model.ChannelGroupMaxUsers {
@@ -508,12 +516,20 @@ func ValidateDirectChannelImportData(data *DirectChannelImportData) *model.AppEr
 	if data.FavoritedBy != nil {
 		for _, favoriter := range *data.FavoritedBy {
 			found := false
-			for _, member := range *data.Members {
-				if favoriter == member {
+			for _, member := range data.Participants {
+				if favoriter == *member.Username {
 					found = true
 					break
 				}
 			}
+			if data.Members != nil {
+				for _, member := range *data.Members {
+					if favoriter == member {
+						found = true
+						break
+					}
+				}
+			}
 			if !found {
 				return model.NewAppError("BulkImport", "app.import.validate_direct_channel_import_data.unknown_favoriter.error", map[string]any{"Username": favoriter}, "", http.StatusBadRequest)
 			}