Inserting and Querying Date with MongoDB and Nodejs

I need some help finding a record by date in mongodb and nodejs.

I add the date to the json object in a scraping script as follows:

jsonObj.last_updated = new Date();

This object is inserted into mongodb. I can see it as follows:

 "last_updated" : "2014-01-22T14:56:59.301Z"

Then in my nodejs script I do a findOne():

 var jObj = JSON.parse(line.toString());

 collection.findOne(jObj,function(err, doc) {
   if (doc){
     console.log(doc._id);
   } else  {
     console.log('not found');
   }
 });

The object is not found. If I remove the last_updated field from the object it is found so it is definitely where the problem is.

If I isolate the field as follows:

collection.findOne({last_updated: '2014-01-22T14:56:59.301Z'},function(err, doc) {
  if (doc){
    console.log(doc._id);
  } else  {
    console.log('not found');
  }
});

Nothing comes back either. What am I doing wrong please?

Answers:

Answer

You need to pass a date object and not a date string.

collection.findOne({last_updated: new Date('2014-01-22T14:56:59.301Z')},function(err, doc) {

The MongoDB driver will transform it into ISODate:

{ 
   "_id" : ObjectId("52dfe0c469631792dba51770"), 
   "last_updated" : ISODate('2014-01-22T14:56:59.301Z') 
}

Check these questions:

Answer

To clarify. What is important to know is that:

  • Yes, you have to pass a Javascript Date object.
  • Yes, it has to be ISODate friendly
  • Yes, from my experience getting this to work, you need to manipulate the date to ISO
  • Yes, working with dates is generally always a tedious process, and mongo is no exception

Here is a working snippet of code, where we do a little bit of date manipulation to ensure Mongo can handle it correctly. In this example, I am using mongoose module and want results for rows whose date attribute is less than (ie. before) the date given as myDate param.

var inputDate = new Date(myDate.toISOString());
MyModel.find({
    'date': { $lte: inputDate }
})
Answer

I recently ran into the same issue and I wanted to add some additional info.

You can insert dates in two ways:

  1. Created on the nodejs server side (e.g. in a ExpressJS script)

example: insert a new object and time stamp it

db.collection('mycollection').findOneAndUpdate({'name': req.body.name}, {
  // only "update" if it's an insert, meaning name is not found
  $setOnInsert: {
    'name': req.body.name,
    'date_added': new Date()
  }
}, { 
  upsert: true
}, (err, result) => {
  if(err) return res.send(err);
  res.send(result);
});
  1. Created on the client side from JS and then sent over the wire using a REST API in a JSON object via a POST request

example:

// Send POST Request here
fetch('addDate', {
  method: 'post',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    'date_added':  new Date()
  })
})

For 1. and 2. you create the dates using the new Date('2014-01-22T14:56:59.301Z') function as explained in the answers above. The difference is that if you do it as in 1. on the server side using the MongoClient package it is stored as a ISODate('2014-01-22T14:56:59.301Z') in MongoDB. If you do it as in 2. on the client side it is stored as a String: '2014-01-22T14:56:59.301Z' in MongoDB.

To query the ISODate object you need to use new Date('2014-01-22T14:56:59.301Z') or ISODate('2014-01-22T14:56:59.301Z') To query the string you use just the string: '2014-01-22T14:56:59.301Z'

Here are some query samples using the mongo shell:

Date stored as String:

db.mycollection.findOne({date_added {$gte:'2018-06-22T00:07:53.688Z'}})

This returns

{
  "_id" : ObjectId("5b2c3dd90078ce3cd484ef21"),
  "name" : "alfons",
  "date_added" : "2018-06-22T00:07:53.688Z"
}

Date stored as ISODate:

db.mycollection.findOne({date_added: {$lte: ISODate('2018-06-26T23:24:37.023Z')}})

or using "new Date" instead:

db.mycollection.findOne({date_added: {$lte: new Date('2018-06-26T23:24:37.023Z')}

This returns:

{
  "_id" : ObjectId("5b2bb21e1954b104e61ff735"),
  "name" : "ceasar",
  "date_added" : ISODate("2018-06-21T14:11:41.323Z")
}
Answer

add Default key in Schema and value to Date.now()

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