Argument passed in must be a single String of 12 bytes or a string of 24 hex characters, Mongoose ObjectId err - mongodb

I actually searched a ton and I saw a ton of mentions of my problem here but none of the things I tried helped me fix the issue i'm having.
I have a Room Scheme that looks like this:
const ObjectId = mongoose.Schema.ObjectId;
const roomSchema = mongoose.Schema({
users: [{
type: ObjectId,
ref: 'User'
}],
messages: [{
type: ObjectId,
ref: 'Message',
}],
post: {
type: ObjectId,
ref: 'Post'
}
});
As you can see I have an array of users with ref to another schema Users
I'm trying to query all the Rooms that has a User ObjectId in it (search ObjectId in an array).
while I can easily get this with querying mongo from cmd using this:
db.users.find({users:ObjectId('THE_OBJECT_ID')});
when I try to get the same while using mongoose it fails with:
Error: Argument passed in must be a single String of 12 bytes or a string of 24 hex characters
Here is how my route and find looks like:
app.route('/rooms/list/:user_id')
.get((req, res) => {
var query = { users: "USER_ID" };
Room.find(query ).populate('messages').then((data) => {
res.status(200).json(data);
}).catch((err) => {
console.log(err);
});
})
I tried to create type of object ID and use it but it still doesn't work.
var mongoose = require('mongoose'),
userId = 'THE_USER_ID';
var id = mongoose.Types.ObjectId(userId);
and than
Rooms.find({'users': id });
but it still doesn't work.
I also tried altering my query search using $in, $elemmatch it worked on cmd but failed when querying using mongoose.
Any help would be appreciated.

Issue :
If you check this :
var query = { users: "USER_ID" };
(Or)
userId = 'THE_USER_ID';
var id = mongoose.Types.ObjectId(userId);
What are you trying to do here ? You are passing in string USER_ID or THE_USER_ID as input and trying to convert it to type of ObjectId(). But string inside ObjectId() has certain restrictions which is why mongoose is failing to convert passed in string value to ObjectId() and getting error'd out.
Try this code :
Code :
const mongoose = require('mongoose');
app.route('/rooms/list/:user_id')
.get((req, res) => {
var query = { users: mongoose.Types.ObjectId(req.params.user_id) };
Room.find(query).populate('messages').then((data) => {
res.status(200).json(data);
}).catch((err) => {
console.log(err);
});
})
Your input should be value of user_id (Which will be string) - Convert it to ObjectId() and then query DB. So value of user_id should be a string that obeys ObjectId()'s restrictions, You can take string from one of existing doc's ObjectId() & test your get api.

Related

mongo mongoose populate subdocument returns null

I am trying to use node & mongoose's populate method to kind of 'join' 2 collections on query. The following is my schema setup:
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var ShopSchema = new Schema({
ssss: { type: Schema.Types.ObjectId, required :true, ref: 'Stat' },
ratings: [RatingSchema]
});
var RatingSchema = new Schema({
stat: { type: Schema.Types.ObjectId, required :true, ref: 'Stat' }
}, {_id: false});
Also I have setup the Stat mongoose model so that the queries works without error (but the result is not what I expected).
I tried to perform the following queries:
ShopSchema.statics.load = function(id, cb) {
this.findOne({
_id: id
}).populate('ssss', '_id stat_id').exec(cb);
};
mongoose.model('Shop', ShopSchema);
This gives me the correct result and the ssss is correctly referenced.
The result is something like this .
"ssss":{"_id":"5406839ad5c5d9c5d47091f0","stat_id":1}
However, the following query gives me the wrong result.
ShopSchema.statics.load = function(id, cb) {
this.findOne({
_id: id
}).populate('ratings.stat', '_id stat_id').exec(cb);
};
mongoose.model('Shop', ShopSchema);
This gives me ratings.stat = null for all results. Could someone tell me what I did wrong? Thanks.
I just found the answer by trial and error.....
in the last example ShopSchema is declared before the RatingSchema. So I am guessing Mongoose doesn't know exactly what is happening inside RatingSchema and making the populate returns an error. So if you declare RatingSchema before the ShopSchema and the populate method is working like a charm..

native update in Sails with Mongo does not work with ObjectId

I wonder what I am doing wrong.
I use Sailsv0.10 and mongo2.6.0 and want to update an array field (using $push) in a collection via native.
My model:
module.exports = {
schema: true,
attributes: {
username: {
type: 'string',
required: true
},
pubs: {
type: 'array',
defaultsTo: []
},
...
My function:
User.native(function (err, collection) {
collection.update({username:aUsernameVariable},{$push:{pubs:aPubsVariable}}, function (err) {
});
It works so far. But why does that not work as a query with the id field?
User.native(function (err, collection) {
collection.update({id:anIdVariable},{$push:{pubs:aPubsVariable}}, function (err) {
});
I definately use the right id for the query to test it.
What am I doing wrong? Or is that a ObjectId type conversion Problem of the Sails-Mongo Adapter
If you want to use native() you can always try the same query directly in your mongo-DB. Because _id is a Object-id you should
var ObjectId = require('mongodb').ObjectID;
User.native(function (err, collection) {
collection.update({_id: new ObjectId(anIdVariable)},{$push:{pubs:aPubsVariable}}, function (err) {
});
You can add the mongo-native-driver to you app with npm install mongodb --save
if you use sailsjs then:
ObjectID = require('sails-mongo/node_modules/mongodb').ObjectID;
var o_id = new ObjectID(req.param('id'));
console.log(o_id );
:)
rhernandez#itemsoft.mx
The problem is because, in mongo relation field, data stores as string - but should be as ObjectID, e.g. ObjectID("56309f327dc5a4133c54bd5e"). I've tried to generate ObjectID in beforeCreate() function
beforeCreate: function(values, cb) {
var ObjectID = require('mongodb').ObjectID;
values.owner = ObjectID(values.owner);
cb();
}
But it throw an error "Argument passed in must be a single String of 12 bytes or a string of 24 hex characters new ObjectId".
I had sails-mongo 0.11.2. Then I'v tried to update - and it helped to me. So check your sails-mongo version. Do not forget to remove manual generating ObjectID from beforeCreate() it will deals by itself
beforeCreate: function(values, cb) {
cb();
}

Is it possible to extract only embedded documents from a Model in Mongoose?

I'd like to run a query on a Model, but only return embedded documents where the query matches. Consider the following...
var EventSchema = new mongoose.Schema({
typ : { type: String },
meta : { type: String }
});
var DaySchema = new mongoose.Schema({
uid: mongoose.Schema.ObjectId,
events: [EventSchema],
dateR: { type: Date, 'default': Date.now }
});
function getem() {
DayModel.find({events.typ : 'magic'}, function(err, days) {
// magic. ideally this would return a list of events rather then days
});
}
That find operation will return a list of DayModel documents. But what I'd really like is a list of EventSchemas alone. Is this possible?
It's not possible to fetch the Event objects directly, but you can restrict which fields your query returns like this:
DayModel.find({events.typ : 'magic'}, ['events'], function(err, days) {
...
});
You will still need to loop through the results to extract the actual embedded fields from the documents returned by the query, however.

Node.js Mongoose.js string to ObjectId function

Is there a function to turn a string into an objectId in node using mongoose? The schema specifies that something is an ObjectId, but when it is saved from a string, mongo tells me it is still just a string. The _id of the object, for instance, is displayed as objectId("blah").
You can do it like so:
var mongoose = require('mongoose');
var id = mongoose.Types.ObjectId('4edd40c86762e0fb12000003');
You can use this also
const { ObjectId } = require('mongodb');
const _id = ObjectId("4eb6e7e7e9b7f4194e000001");
it's simplest way to do it
You can do it like this:
var mongoose = require('mongoose');
var _id = mongoose.mongo.BSONPure.ObjectID.fromHexString("4eb6e7e7e9b7f4194e000001");
EDIT: New standard has fromHexString rather than fromString
Judging from the comments, you are looking for:
mongoose.mongo.BSONPure.ObjectID.isValid
Or
mongoose.Types.ObjectId.isValid
var mongoose = require('mongoose');
var _id = mongoose.mongo.ObjectId("4eb6e7e7e9b7f4194e000001");
I couldn't resolve this method (admittedly I didn't search for long)
mongoose.mongo.BSONPure.ObjectID.fromHexString
If your schema expects the property to be of type ObjectId, the conversion is implicit, at least this seems to be the case in 4.7.8.
You could use something like this however, which gives a bit more flex:
function toObjectId(ids) {
if (ids.constructor === Array) {
return ids.map(mongoose.Types.ObjectId);
}
return mongoose.Types.ObjectId(ids);
}
Just see the below code snippet if you are implementing a REST API through express and mongoose. (Example for ADD)
....
exports.AddSomething = (req,res,next) =>{
const newSomething = new SomeEntity({
_id:new mongoose.Types.ObjectId(), //its very own ID
somethingName:req.body.somethingName,
theForeignKey: mongoose.Types.ObjectId(req.body.theForeignKey)// if you want to pass an object ID
})
}
...
Hope it Helps
If you want to use schema
const yourSchemma = new Schema({
"customerId": {
type: mongoose.Types.ObjectId,
required: true
}
});
If you want to use ObjectId a lot and don`t want to use mongoose.types.ObjectId, you can destructure your declaration:
const {
Types: { ObjectId: ObjectId },
} = require("mongoose");
const id=ObjectId("4edd40c86762e0fb12000003")

How to access a preexisting collection with Mongoose?

I have a large collection of 300 question objects in a database test. I can interact with this collection easily through MongoDB's interactive shell; however, when I try to get the collection through Mongoose in an express.js application I get an empty array.
My question is, how can I access this already existing dataset instead of recreating it in express? Here's some code:
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
mongoose.connect('mongodb://localhost/test');
mongoose.model('question', new Schema({ url: String, text: String, id: Number }));
var questions = mongoose.model('question');
questions.find({}, function(err, data) { console.log(err, data, data.length); });
This outputs:
null [] 0
Mongoose added the ability to specify the collection name under the schema, or as the third argument when declaring the model. Otherwise it will use the pluralized version given by the name you map to the model.
Try something like the following, either schema-mapped:
new Schema({ url: String, text: String, id: Number},
{ collection : 'question' }); // collection name
or model mapped:
mongoose.model('Question',
new Schema({ url: String, text: String, id: Number}),
'question'); // collection name
Here's an abstraction of Will Nathan's answer if anyone just wants an easy copy-paste add-in function:
function find (name, query, cb) {
mongoose.connection.db.collection(name, function (err, collection) {
collection.find(query).toArray(cb);
});
}
simply do find(collection_name, query, callback); to be given the result.
for example, if I have a document { a : 1 } in a collection 'foo' and I want to list its properties, I do this:
find('foo', {a : 1}, function (err, docs) {
console.dir(docs);
});
//output: [ { _id: 4e22118fb83406f66a159da5, a: 1 } ]
You can do something like this, than you you'll access the native mongodb functions inside mongoose:
var mongoose = require("mongoose");
mongoose.connect('mongodb://localhost/local');
var connection = mongoose.connection;
connection.on('error', console.error.bind(console, 'connection error:'));
connection.once('open', function () {
connection.db.collection("YourCollectionName", function(err, collection){
collection.find({}).toArray(function(err, data){
console.log(data); // it will print your collection data
})
});
});
Update 2022
If you get an MongoInvalidArgumentError: The callback form of this helper has been removed. error message, here's the new syntax using async/await:
const mongoose = require("mongoose");
mongoose.connect('mongodb://localhost/productsDB');
const connection = mongoose.connection;
connection.on('error', console.error.bind(console, 'connection error:'));
connection.once('open', async function () {
const collection = connection.db.collection("Products");
collection.find({}).toArray(function(err, data){
console.log(data); // it will print your collection data
});
});
I had the same problem and was able to run a schema-less query using an existing Mongoose connection with the code below. I've added a simple constraint 'a=b' to show where you would add such a constraint:
var action = function (err, collection) {
// Locate all the entries using find
collection.find({'a':'b'}).toArray(function(err, results) {
/* whatever you want to do with the results in node such as the following
res.render('home', {
'title': 'MyTitle',
'data': results
});
*/
});
};
mongoose.connection.db.collection('question', action);
Are you sure you've connected to the db? (I ask because I don't see a port specified)
try:
mongoose.connection.on("open", function(){
console.log("mongodb is connected!!");
});
Also, you can do a "show collections" in mongo shell to see the collections within your db - maybe try adding a record via mongoose and see where it ends up?
From the look of your connection string, you should see the record in the "test" db.
Hope it helps!
Something else that was not obvious, to me at least, was that the when using Mongoose's third parameter to avoid replacing the actual collection with a new one with the same name, the new Schema(...) is actually only a placeholder, and doesn't interfere with the exisitng schema so
var User = mongoose.model('User', new Schema({ url: String, text: String, id: Number}, { collection : 'users' })); // collection name;
User.find({}, function(err, data) { console.log(err, data, data.length);});
works fine and returns all fields - even if the actual (remote) Schema contains none of these fields. Mongoose will still want it as new Schema(...), and a variable almost certainly won't hack it.
Go to MongoDB website, Login > Connect > Connect Application > Copy > Paste in 'database_url' > Collections > Copy/Paste in 'collection' .
var mongoose = require("mongoose");
mongoose.connect(' database_url ');
var conn = mongoose.connection;
conn.on('error', console.error.bind(console, 'connection error:'));
conn.once('open', function () {
conn.db.collection(" collection ", function(err, collection){
collection.find({}).toArray(function(err, data){
console.log(data); // data printed in console
})
});
});
I tried all the answers but nothing worked out, finally got the answer hoe to do it.
var mongoose = require('mongoose');
mongoose.connect('mongodb://0.0.0.0:27017/local');
// let model = require('./test1');
setTimeout(async () => {
let coll = mongoose.connection.db.collection(<Your collection name in plural form>);
// let data = await coll.find({}, {limit:2}).toArray();
// let data = await coll.find({name:"Vishal"}, {limit:2}).toArray();
// let data = await coll.find({name:"Vishal"}, {projection:{player:1, _id:0}}).toArray();
let data = await coll.find({}, {limit:3, sort:{name:-1}}).toArray();
console.log(data);
}, 2000);
I have also mentioned some of the criteria to filter out. Delete and update can also be done by this.
Thanks.
Make sure you're connecting to the right database as well as the right collection within the database.
You can include the name of the database in the connection string.
notice databasename in the following connection string:
var mongoose = require('mongoose');
const connectionString = 'mongodb+srv://username:password#hosturl.net/databasename';
mongoose.connect(connectionString);