Вложенные объекты с Spring Boot, MongoDB

Question

Как получить вложенные объекты с MongoDb с помощью Spring Boot?

У меня есть 3 DTO, BoardResponse, ColumnsResponse, CardResponse.

public class BoardResponse {    
    //id, name, createdBy,createdDate,updatedBy,updatedDate, getters
    List<ColumnResponse> columns = new ArrayList<ColumnResponse>();
    public BoardResponse(KanbanBoard board, List<ColumnResponse> columns) {
        super();
        this.id = board.getId();
        this.name = board.getName();
        this.createdBy = board.getCreatedBy();
        this.createdDate = board.getCreatedDate();
        this.updatedBy = board.getUpdatedBy();
        this.updatedDate = board.getUpdatedDate();
        this.columns = columns;
    }
public class ColumnResponse {   
    //id, name, createdBy,createdDate,updatedBy,updatedDate, getters
    private ObjectId idBoard;
    List<CardResponse> cards = new ArrayList<>();   
    public ColumnResponse(KanbanColumn column, List<CardResponse> cards) {
        super();
        this.id = column.getId();
        this.name = column.getName();
        this.createdBy = column.getCreatedBy();
        this.createdDate = column.getCreatedDate();
        this.updatedBy = column.getUpdatedBy();
        this.updatedDate = column.getUpdatedDate();
        this.id = column.getIdBoard();
        this.idBoard = column.getIdBoard();
        this.cards = cards;     
    }
public class CardResponse {
    //id, name, createdBy,createdDate,updatedBy,updatedDate, getters
    private ObjectId idColumn;
    public CardResponse(KanbanCard card) {
        super();
        this.id = card.getId();
        this.name = card.getName();
        this.createdBy = card.getCreatedBy();
        this.createdDate = card.getCreatedDate();
        this.updatedBy = card.getUpdatedBy();
        this.updatedDate = card.getUpdatedDate();
        this.idColumn = card.getIdColumn();
    }

Я хочу, как сделать вложенные с MongoTemplate, я получил Он использует бизнес-логи c if board exist find by column with board id, if column exist find by card with card id.

Я не знаю, насколько это хорошо.

KanbanBoard, KanbanColumn, такой же, как сущность Board и Column, те же свойства.

public BoardResponse findBoardById(ObjectId id, UserPrincipal currentUser) {
        KanbanBoard board = this.kanbanBoardRepository.findById(id).orElse(null);//find board by id
        //find all columns by board ID within the entity @document KanbanColumn
        List<KanbanColumn> columns = this.kanbanColumnRepository.findAllByIdBoard(board.getId());

        //return list of ColumnResponse DTO
        List<ColumnResponse> columnResponse = columns.stream().map(column -> {
            return new ColumnResponse(column);
        }).collect(Collectors.toList());

        //List Column map
        List<ColumnResponse> columnMap = new ArrayList<>();     

        for (ColumnResponse column : columnResponse) {
            List<CardResponse> cards = this.kanbanCardRepository.findAllByIdColumn(column.getId()).stream()
                    .map(card -> new CardResponse(card)).collect(Collectors.toList());
            column.setCards(cards); //column set list of cards
            columnMap.add(column);//add columns with list of cards inside list of column map
        }       
        //return board with list of column map, with list of cards
        return new BoardResponse(board, columnMap);
    }

Результат

{
    "id": "5e717d6d6e7cbf226074c3fe",
    "name": null,
    "createdBy": "admin",
    "createdDate": 1584495981290,
    "updatedBy": "admin",
    "updatedDate": 1584495981290,
    "columns": [
        {
            "id": "5e72bfa6cc3ff9000ae93c92",
            "name": null,
            "createdBy": "admin",
            "createdDate": 1584578470269,
            "updatedBy": "admin",
            "updatedDate": 1584578470269,
            "idBoard": null,
            "cards": [
                {
                    "id": "5e72de720715f131878b4ed2",
                    "name": "esse é o card",
                    "createdBy": "admin",
                    "createdDate": 1584586354958,
                    "updatedBy": "admin",
                    "updatedDate": 1584586354958,
                    "idColumn": "5e72bfa6cc3ff9000ae93c92"
                }
            ]
        },
        {
            "id": "5e72bfefcc3ff9000ae93c95",
            "name": "coluna criada com sucesso.",
            "createdBy": "admin",
            "createdDate": 1584578543201,
            "updatedBy": "admin",
            "updatedDate": 1584578543201,
            "idBoard": null,
            "cards": [
                {
                    "id": "5e72de550715f131878b4ed0",
                    "name": "esse é o card",
                    "createdBy": "admin",
                    "createdDate": 1584586325485,
                    "updatedBy": "admin",
                    "updatedDate": 1584586325485,
                    "idColumn": "5e72bfefcc3ff9000ae93c95"
                },
                {
                    "id": "5e72de630715f131878b4ed1",
                    "name": "esse é o card",
                    "createdBy": "admin",
                    "createdDate": 1584586339140,
                    "updatedBy": "admin",
                    "updatedDate": 1584586339140,
                    "idColumn": "5e72bfefcc3ff9000ae93c95"
                }
            ]
        }
    ]
}

Answer 1

Использование MongoTemplate, Aggregation, может быть многословным, но результат такой же, как MongoRepository.

public BoardResponse findBoardById(ObjectId id, UserPrincipal currentUser) {
        //board
        AggregationOperation boardId = Aggregation.match(Criteria.where("id").is(id));
        Aggregation boardAggregation = Aggregation.newAggregation(boardId);
        KanbanBoard boards = mongoTemplate.aggregate(boardAggregation, KanbanBoard.class, KanbanBoard.class)
                .getUniqueMappedResult();

        //column idBoard equal board ID
        AggregationOperation ColumnIdBoardIsLikeBoardId = Aggregation
                .match(Criteria.where("idBoard").is(boards.getId()));
        Aggregation columnAggregation = Aggregation.newAggregation(ColumnIdBoardIsLikeBoardId);
        List<ColumnResponse> listaColumns = mongoTemplate
                .aggregate(columnAggregation, KanbanColumn.class, ColumnResponse.class).getMappedResults();

        //map every column, column set list of cards
        listaColumns.stream().map(column -> {
            List<CardResponse> cards =
                    // find all cards by column ID
                    this.kanbanCardRepository.findAllByIdColumn(column.getId()).stream()
                            .map(card -> new CardResponse(card)).collect(Collectors.toList());
            column.setCards(cards);
            return column;
        }).collect(Collectors.toList());    
        //board DTO set board, list of columns with list of cards
        return new BoardResponse(boards, listaColumns);
    }