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checking if certain row exist in nedb

i have looked all around trying to find a solution for this but i cant seem to find it
i am trying to see if a certain row exist in my nedb database and if it doesnt exist insert something but if it does exist then just move along here is what i have tried
function newAgent(pcName){
socket.broadcast.emit('newAgent', pcName)
agentList.find({agentName: { $nin: pcName}}, function(err, docs) {
agentList.insert({agentName: pcName}, function (err) {});
});
}
now i might be doing something stupid but im new to nedb so i have no idea what to use

How about trying something like this
function newAgent(pcName){
socket.broadcast.emit('newAgent', pcName)
agentList.find({agentName: { $in: pcName}}, function(err, docs) {
if(null === docs){
agentList.insert({agentName: pcName}, function (err) {});
} else {
//since it exists you might want update
agentList.update({
pcName: pcName
}, {
$set: {
//call fields to be updated
}
}, {}, callback);
}
});
}

Callback function running but not the main function

I have this code inside of a route and when I run the debugger, the theDocu2.save(); function is being run and then the socket emit but I never see the $set run which sets the new mongoose values. Any reason for this? Also, in the debugger, values like bidTime and bidAmount are equal to the previous values that were set the last time this route was run.
User.findByIdAndUpdate(req.session.passport.user, {
$set: {
bidDetails: {
bidAmount: req.body.bidAmount,
bidLocation: 'Market Square',
bidTime: moment().format()
}
}
}, function(err, theDocu2) {
if (err) {
return console.log(err);
}
theDocu2.save();
io.to(theDocu2.email).emit('activeBid', {
activeBid: req.body.bidAmount,
bidTime: theDocu2.bidDetails.bidTime
});
});

Unable to access writeresult from remove() in callback

I'm pretty new to Mongodb and have so far successfully used Find, Insert, Update methods. However, with Delete function I am not able to access WriteResult
Insert (Works)
productCollection.insert(newProduct, function (err, result) {
callBack(err, { message: result["insertedCount"] + ' product created successfully.' });
});
Find (Works)
productCollection.find({}).toArray(function (err, docs) {
callBack(err, { product: docs });
});
Delete (Has Issues)
productCollection.remove({ id: pId }, { justOne: 1 }, function (err, result) {
callBack(err, { message: result});
});
Here when I return {message: result} I get
{
"message": {
"ok": 1,
"n": 0
}
}
But I want to actually read "n" from Result to show no of documents deleted
Tried following
{ message: result["n"] }
{ message: result["nRemoved"] }
But in both cases it returns empty object {}.

According to the 2.0 version of Node.js MongoDB Driver API, remove() method is deprecated, you can use removeOne() method instead:
http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#remove
In order to receive number of documents that were removed, you need to use safe mode to ensure removal of documents. To do this, specify write concern by passing {w: 1} to removeOne() function:
productCollection.removeOne({ _id: pId }, { w:1 }, function(err, r) {
// number of records removed: r.result.n
callBack(err, { message: r });
});
Hope this helps.

Thanks Yelizaveta for pointing out the deprecated method. However in my case, following worked
productCollection.removeOne({ id: pId }, { w: 1 }, function (err, r) {
callBack(err, { message: r.result["n"]});
});
I could not get r.result.n working instead r.result["n"] worked, which I don't understand.

angular push adds operator that that results in MongoError

I am implementing the tutorial on the mean stack https://www.youtube.com/watch?v=AEE7DY2AYvI
I am adding a delete feature to remove items from the database on a button click
My client side controller has the following 2 functions to add to db and remove
$scope.createMeetup = function() {
var meetup = new Meetup();
meetup.name = $scope.meetupName;
meetup.$save(function (result) {
$scope.meetups.push(result);
$scope.meetupName = '';
});
}
$scope.deleteMeetup = function() {
item = $scope.meetups[0];
console.log("deleting meetup: " + item["name"]);
Meetup.delete(item);
scope.meetups.shift();
}
My server side has the following code
module.exports.create = function (req, res) {
var meetup = new Meetup(req.body);
meetup.save(function (err, result) {
res.json(result);
});
}
module.exports.remove = function(req, res) {
console.log("GOING TO REMOVE!!!");
console.log(req.query);
item = req.query;
Meetup.remove(item, function (err, results) {
console.log("done");
console.log(err);
console.log(results);
});
}
When I run my code and if I delete an already loaded item in the list, it is removed from Mongodb just fine. But if I add an item to the list and I do not refresh the page, it results in an error at my server that appears as
GOING TO REMOVE!!!
{ '$resolved': 'true',
__v: '0',
_id: '54ec04e70398fab504085178',
name: 'j' }
done
{ [MongoError: unknown top level operator: $resolved]
name: 'MongoError',
code: 2,
err: 'unknown top level operator: $resolved' }
null
I if I refresh the page, the it gets deleted fine. But if I added the entry, angular seems to be adding a new variable $resolved. Why is that happening?
Also another question, What is the proper way to call delete? I call it now but I am not able to put a callback. I want a callback which returns and then I shift the list of items. I tried adding a callback but the code never reaches it.
ie I tried the following
/*
Meetup.delete(item, function () {
console.log("In callback!!");
console.log(returnValue);
console.log(responseHeaders);
$scope.meetups.splice(item);
});
*/
/*Meetup.delete(item,
function (returnValue, responseHeaders) {
console.log("In callback!!");
console.log(returnValue);
console.log(responseHeaders);
$scope.meetups.splice(item);
},
function (httpResponse){
// error handling here
console.log("Need to handle errors");
});
*/
I am very new to node and am confused. Any help is very, very appreciated

Looks like it possible to call item.delete instead of Meetup.delete(item). You can call same methods on model instance. It prevent sending angular properties to server.
But better to make a rest API with delete method
DELETE /meetups/:id
and send just a _id
Meetup.remove({id: item._id});

Is it possible to update an already open document in mongodb

In JS, Is there a better way of doing the following:
I'm finding a user, and then checking password, then I wish to update the same users' document.
Can I leverage the already open document (var doc) for updating? Or do as the code below does and re-search for name:name when updating.
user_collection.findOne({ name:name }, function(err, doc) {
if(err)
throw err;
if(doc) {
// verify doc.password etc
user_collection.update({ name:name }, {$set: { last_joined:last_joined }}, { upsert:true }, function(err, doc) {
if(err) {
// log error
}
});
}
});

Yes - use the save method.
The document you have in doc is an in-memory copy of the record in the database. If you want to modify it then save it to the database, you need to either use the update method as you do, or use save(modified_doc).
Note: as freakish said, you probably should use user_collection.update({ _id: doc._id }, ...) instead of searching for name again, since it may not be unique.