Mongoose deleting (pull) a document within an array, does not work with ObjectID

Question

I have the following mongoose schema:

user = {
    \"userId\" : \"myId\",
    \"connections\":
    [{
        \"dateConnectedUnix\": 1334567891,
        \"is         


        

Answer 1

user: {
 _id: ObjectId('5ccf3fa47a8f8b12b0dce204'),
 name: 'Test',
 posts: [
  ObjectId("5cd07ee05c08f51af8d23b64"),
  ObjectId("5cd07ee05c08f51af8d23c52")
 ]
}

Remove a single post from posts array

user.posts.pull("5cd07ee05c08f51af8d23b64"); user.save();

Answer 2

mongoose: 4.11.11
What have worked for me is the following syntax:

const removeTansactionFromUser = (userId, connectionId) => {
    return User.findByIdAndUpdate(userId, { $pull: { "connections": connectionId} }, {'new': true} );
};

Mongoose support id in string format or ObjectId format.
Tip: new ObjectId(stringId) to switch from string to ObjectId

Answer 3

I have a document like

I have to delete address from address array

After searching lots on internet I found the solution

 Customer.findOneAndUpdate(query, {$pull: {address: addressId}}, function(err, data){
        if(err) {
          return res.status(500).json({'error' : 'error in deleting address'});
        }

        res.json(data);

      });

Answer 4

It seems that the above code would not work. It should not even have worked for the first example I gave.

In the end I was supported by this answer here: MongoDB, remove object from array

Here is my working code:

userAccounts.update( 
      { userId: usr.userId },
      { $pull: { connections : { _id : connId } } },
      { safe: true },
      function removeConnectionsCB(err, obj) {
          ...
      });

Answer 5

In mongoose 5.8.11, this $pull: { ... } didn't work for me, so far not sure why. So I overcame it in my controller this way:

exports.removePost = async (req, res, next) => {
  const postId = req.params.postId;
  try {
    const foundPost = await Post.findById(postId);
    const foundUser = await User.findById(req.userId);
    if (!foundPost || !foundUser) {
      const err = new Error(
        'Could not find post / user.',
      );
      err.statusCode = 404;
      throw err;
    }
    // delete post from posts collection:
    await Post.findByIdAndRemove(postId);
    // also delete that post from posts array of id's in user's collection:
    foundUser.posts.pull({ _id: postId });
    await foundUser.save();
    res.status(200).json({ message: 'Deleted post.' });
  } catch (err) {
    // ...
  }
};

Answer 6

To use update with ObjectId, you should use ObjectId object instead of string representation :

var ObjectId = require('mongoose').Types.ObjectId;

userAccounts.update({'connections._id': new ObjectId('1234-someId-6789') }, 
                {$pull: { 'connections._id': new ObjectId('1234-someId-6789') }}, 
                function (err,val) {
                    console.log(val)
                });