Question

我在使用mongoose将一些数据保存到Mongo时遇到了问题。

在我的数据库模块中，我正在做：

  self.addMove = function (gameId, move, callback) {
    Game.findById(gameId, function (err, game) {
      if (err)
        callback(err);
      else {
        game.newMove = move; //apply new move
        game.save(Game.transformState(callback)); //save the game
      }
    });
  };

其中newMove在GameSchema中被定义为虚拟方法

GameSchema.virtual('newMove').set(function (move) {
  if (move.player !== move.piece[0])
    return;
  if (allowedMove(move)) { //if piece is allowed to move
    var from = positionToIndex(move.from),
      to = positionToIndex(move.to);
    this._field[to] = this._field[from]; //move it
    this._field[from] = "";
  }
});

和transformState作为静态方法

GameSchema.statics.transformState = function (callback) {
  return function (err, data) {
    if (err)
      callback(err);
    else
      callback(null, {
        _id: data._id,
        moves: data.moves,
        field: data.field //data.field transforms 1D array into 2D client-useable array
      });
  };
};

我如何调用addMove：

socket.on('addMove', function (msg) {
  console.log('New move: ' + msg);
  var msg = JSON.parse(msg);
  db.addMove(msg._id, msg.move, function (err, data) {
    if(!err)
      io.emit('getState', JSON.stringify(data));
  });
});

根据要求，我的GameSchema：

GameSchema = new Schema({
  moves: [MoveSchema],
  _field: {
    type: [String],
    default: ["WR", "WN", "WB", "WQ", "WK", "WB", "WN", "WR", "WP", "WP", "WP", "WP", "WP", "WP", "WP", "WP", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "BP", "BP", "BP", "BP", "BP", "BP", "BP", "BP", "BR", "BN", "BB", "BQ", "BK", "BB", "BN", "BR"]
  }
})

作为奖励，这是我第二次请求游戏状态的方式：

//sockets.js
socket.on('getState', function (msg) {
  console.log('User requested game state!');
  var msg = JSON.parse(msg);
  db.getGame(msg._id, function (err, data) {
    if(!err)
      io.emit('getState', JSON.stringify(data));
  });
});

//database.js
self.getGame = function (id, callback) {
  Game.findById(id, Game.transformState(callback));
};

正如您所看到的，每当我从客户端获得新动作时，我都会修改当前游戏区域并保存该游戏。当我用game.save(Game.transformState(callback));保存它时，它已被保存了＃34;这意味着回调中的数据是正确的。但如果我再次尝试请求游戏状态，我可以看到它没有被保存。我也尝试手动检查MongoDB，但确实没有保存。我试图解释的是，在行game.save(Game.transformState(callback));中，函数callback以更新的游戏状态执行，我可以在客户端看到它，但状态实际上没有保存在数据库中。

Answer 1

显然，如果直接修改数组，mongoose不会检测字段是否已更改。为了触发检测，我使用了this.markModified('_field');

我还发现了一些其他的方法： Mongoose: assign field of type 'array of Strings'

Mongoose在报告保存数据时不保存数据

1 个答案: