猫鼬 - 更改单个文档的 ttl [英] mongoose - change ttl for a single document

问题描述

我有一件非常确定的事情要完成，并且在我自己编写整个代码之前，我想确保它在 mongoose/mongoDB 中是不可能的.我检查了 mongoose-ttl 的 nodejs 和几个论坛，但没有找到我需要的东西.这是:

我有一个带有日期字段 createDate 的架构.现在我希望在该字段上放置一个 TTL，到目前为止还不错，我可以这样做(5000 秒后到期):createDate: {type: Date, default: Date.now, expires: 5000}

但我希望我的用户能够对他们喜欢的文档进行投票"，这样这些文档将有更长的生命周期，而无需更改我收藏中的其他文档.那么，一旦用户告诉我他喜欢使用 mongoose 或其他现有 npm 相关模块的文档，我可以以某种方式更改单个文档的 TTL 吗?

谢谢

解决方案

已经一年多了，但是这可能对其他人有用，所以这里是我的答案:

我试图完成同样的事情，以便在条目删除后允许一个宽限期，以便用户可以在之后取消操作.

正如 Mike Bennett 所述，您可以使用 TTL 索引 使文档在特定时钟时间过期.>

你必须创建一个索引，将 expireAfterSeconds 设置为零:

db.yourCollection.createIndex({ "expireAt": 1 }, { expireAfterSeconds: 0 });

这不会影响您集合中的任何文档，除非您像这样在特定文档上设置 expireAfterSeconds:

db.log_events.insert( {"expireAt": new Date('July 22, 2013 14:00:00'),日志事件":2，"logMessage": "成功！"})

猫鼬中的例子

型号

var BeerSchema = new Schema({名称: {类型:字符串，独特:真实，要求:真实},描述:字符串，酒精:数字，价格:数量，createdAt: { 类型:日期，默认值:Date.now }expireAt: { type: Date, default: undefined }//你不需要设置这个默认值，但我喜欢它的语义清晰});BeerSchema.index({ "expireAt": 1 }, { expireAfterSeconds: 0 });

宽限期删除

使用 moment 进行日期操作

exports.deleteBeer = function(id) {var deferred = q.defer();Beer.update(id, { expireAt: moment().add(10, 'seconds') }, function(err, data) {如果(错误){deferred.reject(err);} 别的 {deferred.resolve(data);}});返回 deferred.promise;};

恢复删除

使用 moment 进行日期操作

exports.undeleteBeer = function(id) {var deferred = q.defer();//设置 expireAt 为 undefinedBeer.update(id, { $unset: { expireAt: 1 }}, function(err, data) {如果(错误){deferred.reject(err);} 别的 {deferred.resolve(data);}});返回 deferred.promise;};

I have a very certain thing i want to accomplish, and I wanted to make sure it is not possible in mongoose/mongoDB before I go and code the whole thing myself. I checked mongoose-ttl for nodejs and several forums and didn't find quite what I need. here it is:

I have a schema with a date field createDate. Now i wish to place a TTL on that field, so far so good, i can do it like so (expiration in 5000 seconds): createDate: {type: Date, default: Date.now, expires: 5000}

but I would like my users to be able to "up vote" documents they like so those documents will get a longer period of time to live, without changing the other documents in my collection. So, Can i change a TTL of a SINGLE document somehow once a user tells me he likes that document using mongoose or other existing npm related modules?

thank you

解决方案

It has been more than a year, but this may be useful for others, so here is my answer:

I was trying accomplish this same thing, in order to allow a grace period after an entry deletion, so the user can cancel the operation afterwards.

As stated by Mike Bennett, you can use a TTL index making documents expire at a specific clock time.

Yo have to create an index, setting the expireAfterSeconds to zero:

db.yourCollection.createIndex({ "expireAt": 1 }, { expireAfterSeconds: 0 });

This will not affect any of the documents in your collection, unless you set expireAfterSeconds on a particular document like so:

db.log_events.insert( {
   "expireAt": new Date('July 22, 2013 14:00:00'),
   "logEvent": 2,
   "logMessage": "Success!"
} )

Example in mongoose

Model

var BeerSchema = new Schema({
  name: {
    type: String,
    unique: true,
    required: true
  },
  description: String,
  alcohol: Number,
  price: Number,
  createdAt: { type: Date, default: Date.now }
  expireAt: { type: Date, default: undefined } // you don't need to set this default, but I like it there for semantic clearness
});

BeerSchema.index({ "expireAt": 1 }, { expireAfterSeconds: 0 });

Deletion with grace period

Uses moment for date manipulation

exports.deleteBeer = function(id) {
  var deferred = q.defer();

  Beer.update(id, { expireAt: moment().add(10, 'seconds') }, function(err, data) {
    if(err) {
      deferred.reject(err);
    } else {
      deferred.resolve(data);
    }
  });
  return deferred.promise;
};

Revert deletion

Uses moment for date manipulation

exports.undeleteBeer = function(id) {
  var deferred = q.defer();
  // Set expireAt to undefined
  Beer.update(id, { $unset: { expireAt: 1 }}, function(err, data) {
    if(err) {
      deferred.reject(err);
    } else {
      deferred.resolve(data);
    }
  });
  return deferred.promise;
};

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