javascript对象转mongodb结构，不会冒泡

Question

所以为了进一步解释标题，我正在尝试将javascript 对象转换为MongoDB结构以进行查询。

大家可能知道，mongodb在查询数据库的时候是严格匹配的。换句话说，文档必须完全匹配。

例如，假设我们有一个具有以下布局的 mongo 文档:

{
  location: {
    city: "Some city",
    state: "Some state",
    color: {
      red: "and yellow",
      green: "and gold"
    }
  }
}

要查询城市，您可以执行以下操作:

{
  "location.city": "Some city"
}

而不是:

{
  "location": {
    "city": "Some city"
  }
}

这就是这个函数诞生的原因。下面这个函数好像没有？冒泡？结果向上对象。此外，结构中的旧对象也被复制。

函数:

function query_to_mongo(query, root) {
  var new_query = {};

  for (var property in query) {
    if (!(typeof(query))[property]) {

      if (!root) { // root object.
        root = property;

        // Property value is type of object.
        if (typeof(query[property]) === 'object') {
          new_query = query_to_mongo(query[property], property);
        } else {        
          new_query[property] = query[property];
        }

      } else {

        console.log('Last prop: ' + root + '.' + property);

        // Property value is type of object.
        if (typeof(query[property]) === 'object') {
          new_query[root + '.' + property] = query_to_mongo(query[property], property);
        } else {
          new_query[root + '.' + property] = query[property];

      }

    } 
  }

  return new_query;
}

代码:

var this_query = {
  location: {
    city: "Some city",
    state: "Some state",
    color: {
      red: "and yellow",
      green: "and gold"
    }
  }
};

console.log( query_to_mongo(this_query) );

结果:

{
  location.city: "Some city",
  location.color: [object Object] {
    color.green: "and gold",
    color.red: "and yellow"
  },
  location.state: "Some state"
}

预期:

{
  location.city: "Some city",
  location.color.green: "and gold",
  location.color.red: "and yellow",
  location.state: "Some state"
}

所以问题是，发生了什么？此外，是否有更好、更优雅的方式来满足我的需求？

Answer 1

所以，几个小时后，我终于想出了如何完成我的任务。此外，我还决定添加一张我将允许使用的运营商 map 。

代码:

function apply_operator(op) {
  switch(op) {
    case "$exists": return true;
    case "$in": return true;
    default: return false;
  }
}

function query_to_mongo(query) {
  var new_query = {};

  (function(obj, val) {
    val = val || '';

    if (typeof(obj) !== 'object')  return true;

    for (var property in obj) {
      if (arguments.callee(obj[property], val + "." + property)) {
        if (apply_operator(property)) {
          new_query[val.substring(1)] = JSON.parse('{"' + property + '": "' + obj[property] + '"}');
        } else {
          if (val.substring(1)) {
            new_query[val.substring(1) + "." + property] = obj[property];
          } else {
            new_query[property] = obj[property];
          }
        }
      }
    }
    return false;
  })(query);

  return new_query;
}

var this_query = {
  location: {
    city: "Some city",
    state: "Some state",
    color: {
      red: "and yellow",
      green: "and gold",
      gold: {
        best: "ever"
      }
    }
  },
  exister: { "$exists": true }
};

console.log( query_to_mongo(this_query) );

结果是:

[object Object] {
  exister: [object Object] {
    $exists: "true"
  },
  location.city: "Some city",
  location.color.gold.best: "ever",
  location.color.green: "and gold",
  location.color.red: "and yellow",
  location.state: "Some state"
}