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how to update 2nd schema using node js (mongdb)

I am trying to update my 2nd schema which having reference in first schema
ownerSchema.js
var ownerSchema = Schema({
fname : String,
lname : String,
shopPlace : {
type: Schema.Types.ObjectId,
ref: 'Shop'
}
});
var Owner = mongoose.model('Owner', ownerSchema);
shopSchema.js
var shopSchema = Schema({
shopName : String,
location : String,
startDate : Date,
endDate : Date
});
var Shop = mongoose.model('Shop', shopSchema);
so I am trying to update my schema like this
const update = async (req, res) => {
const { id } = req.params;
let update = {};
if (req.body.fname) update.fname = req.body.fname;
if (req.body.lname) update.lname = req.body.lname;
if (req.body.shopPlace.shopName) update.shopPlace.shopName = req.body.shopPlace.shopName;
if (req.body.shopPlace.location) update.shopPlace.location = req.body.shopPlace.location;
let newOwmer = new Owner.updateOne(
{ ownerId: id },
{
$set: update,
},
{ runValidators: true }
);
};
I am trying to update shop but its not working and where am i wrong i dont know

const update = async (req, res) => {
const { id } = req.params;
let update = {};
let updateShop = {}
if (req.body.fname) update.fname = req.body.fname;
if (req.body.lname) update.lname = req.body.lname;
if (req.body.shopPlace.shopName) updateShop.shopPlace.shopName = req.body.shopPlace.shopName;
if (req.body.shopPlace.location) updateShop.shopPlace.location = req.body.shopPlace.location;
// get shopPlace _id from Owner
const { shopPlace } = await Owner.findOneAndUpdate(
{ _id: id },
{
$set: update,
},
{ new:true}
);
// here you must have the document you just updated. Just recover the id of the shop to modify it in turn
// update shop
let newShop = await Shop.findOneAndUpdate(
{ _id: shopPlace },
{
$set: updateShop,
},
{new:true}
);
};

How to add mongoose transaction and create a document?

I want to add a mongoose transaction in the POST method. When creating the transaction it should be creating a document called stock. Can anybody help me figure out what should I do here? I have a node/express/mongoose app with the following:
GoodsRecivedNote controller
router.post('/', async (req, res) => {
const session = await mongoose.startSession()
try {
const _id = await getNextSequence('goodsReceivedNote')
req.body.id = _id
const goodsReceivedNote = new GoodsReceivedNote(req.body)
const stocks = new Stock(req.body)
await goodsReceivedNote.save()
//use mongoose transaction
//creates a loop(data get from the arry called cart in goodsrecivednote)
for (const item of data) {
//insert stock modal(orderNo, packingId, orderSize, poNumber)
item.create({})
//insert(data, {session})
}
await session.commitTransaction()
res.sendStatus(200)
} catch (error) {
await session.abortTransaction()
return res.sendStatus(500)
} finally {
session.endSession()
}
})
GoodsRecivedNote model
const goodsReceivedNoteSchema = new Schema(
{
id: Number,
poNumber: String,
orderedDate: String,
supplier: String,
orderNo: String,
cart: [
{
packingId: Number,
actualSize: String,
orderSize: String,
brandId: Number,
artWork: String,
receivedQty: Number,
grnDate: String,
},
],
},
)
module.exports = mongoose.model(
'GoodsReceivedNote',
goodsReceivedNoteSchema
)
Stock model
const stockSchema = new Schema(
{
id: Number,
poNumber: Number,
orderNo: String,
packingId: Number,
orderSize: String,
receivedQty: Number,
availableQty: Number,
},
)
module.exports = mongoose.model(
'Stock',
stockSchema
)

Maybe you can try something like this
const session = await mongoose.startSession()
session.startTransaction()
const opts = { session }
const stocks = await new Stock(req.body).save(opts)
await goodsReceivedNote.save(opts)
...the rest of your code
When ever you call Save Update or Delete please add opts as option

Answer by 21bn gets the work done but withTransaction() is way better than startTransaction().
I recommend you use withTransaction instead.
const session = await mongoose.startSession();
await session.withTransaction(async (session) => {
// For create..
collection.create({something:"something"},{session:session});
});
For insertmany, updatemany, the rule is basically the same..
collection.updateMany({find_something:"something"},{name:"Some name"},{session:session});
If you want to find a document using session..
collection.findOne({_id: "some_id"}).session(session));

Cannot populate fields in express and Mongodb

I have two models Post and Users and I want to populate the posts fields
const PostSchema = new Schema({
text: {
type: String
},
author: {
type: mongoose.Schema.Types.ObjectId,
ref: 'user'
}
})
const UserSchema = new Schema({
username: {
type: String,
}
})
router.post('/', async (req,res) => {
try {
let joe = new User({username: "joe"})
await joe.save()
let postText = {text: "my name is joe", author: joe._id}
let postByJoe = new Post(postText)
await postByJoe.save()
let users = User.find().populate('author')
res.json({users})
} catch (error) {
console.log(error.message)
res.json(error.message)
}
})
The problem is that I get an error and I don't know what to make of it. I'm not sure at all what the issue is. Any help would be greatly appreciated
"Converting circular structure to JSON\n --> starting at object with constructor 'NativeTopology'\n | property 's' -> object with constructor 'Object'\n | property 'sessionPool' -> object with constructor 'ServerSessionPool'\n --- property 'topology' closes the circle"

What you have in your schema is different, you can only populate the Schema.Types.ObjectId field in your schema. Seems you are trying to populate the author field of the Post model.
Replace this line let users = User.find().populate('author') with this let users = Post.find().populate('user') Your code should be like the one below:
router.post('/', async (req,res) => {
try {
let joe = new User({username: "joe"})
await joe.save()
let postText = {text: "my name is joe", author: joe._id}
let postByJoe = new Post(postText)
await postByJoe.save()
let data = await Post.find().populate('user')
// map through the object returned
const users = data.map((user) => user)
res.json({users})
} catch (error) {
console.log(error.message)
res.json(error.message)
}
})
Read more about mongoose population here

How can I loop through this array inside this instance of my mongoose model?

const postSchema = new mongoose.Schema({
post:[
{postId: String},
{commentComponent: [
{comment: [String]},
]}
]
})
const Posts = mongoose.model('Posts', postSchema)
This is the definition of the schema for modeling the mongodb
const postLinks = await getPostLinks();
const posts = new Posts({
for (let i = 0; i < postLinks.length; i++) {
const comment = await getComment(postLinks[i]) // here it takes postLinks as a paramaeter to get an array of comment
post: [
{postId: postLinks[i]},
{commentComponent: [
{comment: comment}
]}
]
}
})
const result = await posts.save()
is there a way of iterating inside this instance because the for loop here is not working

You need to pass an object to the Posts constructor with a property called post (which probably should be called posts, but will keep the original name below), and for this property, you need to specify an array.
This array can be built by using Array.prototype.map and Promise.all:
const post = await Promise.all(
postLinks.map(async (postLink) => {
const comment = await getComment(postLink);
return {
postId: postLink,
commentComponent: [{ comment }],
};
})
);
const posts = new Posts({ post });
const result = await posts.save();
But if you prefer, you can use the traditional for-loop (more similar to what you were trying to do) as well:
const post = [];
for (let i = 0; i < postLinks.length; i++) {
const comment = await getComment(postLinks[i]);
post.push({
postId: postLinks[i]},
commentComponent: [{ comment }]
});
}
const posts = new Posts({ post });
const result = await posts.save();

Based on your code example I am not certain what you are attempting to do. When using a Model and trying to create you can think of as a new singular record. If you are trying to insert many links into a single record I would suggest comma separating them then inserting that into your MongoDB.
But you cannot iterate inside your Posts class like that.
If I were you I would set up my file something like this:
file: models/Post.js:
const mongoose = require('mongoose');
const PostSchema = new mongoose.Schema({
text: {
type: String,
trim: true,
required: [true, 'Please add some text']
},
link: {
type: String,
required: [true, 'Please add link']
},
createdAt: {
type: Date,
default: Date.now
}
});
module.exports = mongoose.model('Post', PostSchema);
Then create a controller js file
file: controllers/posts.js:
const Post = require('../models/Post');
// #desc Add Post
// #route POST /api/v1/posts
// #access Public
exports.addPost = async (req, res, next) => {
try {
// get post data from the request
// mongo returns a promise so await on it
const post = await Post.create(req.body);
return res.status(201).json({
success: true,
data: post
});
} catch (err) {
if(err.name === 'ValidationError') {
const messages = Object.values(err.errors).map(val => val.message);
return res.status(400).json({
success: false,
error: messages
});
} else {
return res.status(500).json({
success: false,
error: 'Server Error'
});
}
}
}
then in your router file, you can use your controller:
routes/post.js
const express = require('express');
const router = express.Router();
const { addPost } = require('../controllers/posts');
router
.route('/')
.post(addPost);
module.exports = router;

node.js mongodb select document by _id node-mongodb-native

I'm trying to select a document by id
I've tried:
collection.update({ "_id": { "$oid": + theidID } }
collection.update({ "_id": theidID }
collection.update({ "_id.$oid": theidID }}
Also tried:
collection.update({ _id: new ObjectID(theidID ) }
This gives me an error 500...
var mongo = require('mongodb')
var BSON = mongo.BSONPure;
var o_id = new BSON.ObjectID(theidID );
collection.update({ _id: o_id }
None of these work. How to select by _id?

var mongo = require('mongodb');
var o_id = new mongo.ObjectID(theidID);
collection.update({'_id': o_id});

This the approach that worked for me.
var ObjectId = require('mongodb').ObjectID;
var get_by_id = function(id, callback) {
console.log("find by: "+ id);
get_collection(function(collection) {
collection.findOne({"_id": new ObjectId(id)}, function(err, doc) {
callback(doc);
});
});
}

now you can just use this:
var ObjectID = require('mongodb').ObjectID;
var o_id = new ObjectID("yourObjectIdString");
....
collection.update({'_id': o_id});
You can see documentation here

With native_parser:false:
var BSON = require('mongodb').BSONPure;
var o_id = BSON.ObjectID.createFromHexString(theidID);
With native_parser:true:
var BSON = require('mongodb').BSONNative;
var o_id = BSON.ObjectID.createFromHexString(theidID);

I just used this code in Node.js app in controller file, and it works:
var ObjectId = require('mongodb').ObjectId;
...
User.findOne({_id:ObjectId("5abf2eaa1068113f1e")})
.exec(function(err,data){
// do stuff
})
do not forget to install "mongodb" before, and if you are using encryption of your passwords with bcrypt with "presave", be sure that you will not encrypt password after each modification of the record in DB.

/* get id */
const id = request.params.id; // string "5d88733be8e32529c8b21f11"
/* set object id */
const ObjectId = require('mongodb').ObjectID;
/* filter */
collection.update({
"_id": ObjectId(id)
} )

ObjectId reports deprecated when called inside find() function in "mongodb": "^4.1.2" if the ObjectId is imported like this
const ObjectId = require('mongodb').ObjectID;
instead, when I import it with named import there is no deprecated warning
const { MongoClient, ObjectId } = require("mongodb");
then I can call it regularly
const findResult = await collection.find({_id: ObjectId(id)}).toArray();

This is what worked for me.
Using mongoDB
const mongoDB = require('mongodb')
Then at the bottom where I am making my express get call.
router.get('/users/:id', (req, res) => {
const id = req.params.id;
var o_id = new mongoDB.ObjectID(id);
const usersCollection = database.collection('users');
usersCollection.findOne({
_id: o_id
})
.then(userFound => {
if (!userFound){
return res.status(404).end();
}
// console.log(json(userFound));
return res.status(200).json(userFound)
})
.catch(err => console.log(err));
});`

The answer depends upon the variable type you are passing in as the id. I pulled an object id by doing a query and storing my account_id as the ._id attribute. Using this method you simply query using the mongo id.
// begin account-manager.js
var MongoDB = require('mongodb').Db;
var dbPort = 27017;
var dbHost = '127.0.0.1';
var dbName = 'sample_db';
db = new MongoDB(dbName, new Server(dbHost, dbPort, {auto_reconnect: true}), {w: 1});
var accounts = db.collection('accounts');
exports.getAccountById = function(id, callback)
{
accounts.findOne({_id: id},
function(e, res) {
if (e) {
callback(e)
}
else {
callback(null, res)
}
});
}
// end account-manager.js
// my test file
var AM = require('../app/server/modules/account-manager');
it("should find an account by id", function(done) {
AM.getAllRecords(function(error, allRecords){
console.log(error,'error')
if(error === null) {
console.log(allRecords[0]._id)
// console.log('error is null',"record one id", allRecords[0]._id)
AM.getAccountById(
allRecords[0]._id,
function(e,response){
console.log(response,"response")
if(response) {
console.log("testing " + allRecords[0].name + " is equal to " + response.name)
expect(response.name).toEqual(allRecords[0].name);
done();
}
}
)
}
})
});

If you use Mongosee, you can simplify the function
FindById:
this replace in mongodb: "_id" : ObjectId("xyadsdd434434343"),
example:
// find adventure by id and execute
Adventure.findById('xyadsdd434434343', function (err, adventure) {});
https://mongoosejs.com/docs/api.html#model_Model.findById

I'm using client "mongodb": "^3.6.2" and server version 4.4.1
// where 1 is your document id
const document = await db.collection(collection).findOne({ _id: '1' })
console.log(document)
If you want to copy and paste here's all you need.
const { MongoClient } = require('mongodb')
const uri = '...'
const mongoDb = '...'
const options = {}
;(async () => {
const client = new MongoClient(uri, options)
await client.connect()
const db = client.db(mongoDb)
const document = await db.collection(collection).findOne({ _id: '1' })
console.log(document)
)}()

In Mongoose, the Model.findById() function is used to find one document by its _id. The findById() function takes in a single parameter, the document id. It returns a promise that resolves to the Mongoose document if MongoDB found a document with the given id, or null if no document was found.
const schema = new mongoose.Schema({ _id: Number }, { versionKey: false });
const Model = mongoose.model('MyModel', schema);
await Model.create({ _id: 1 });
// `{ _id: 1 }`
await Model.findById(1);
// `null` because no document was found
await Model.findById(2);
When you call findById(_id), Mongoose calls findOne({ _id }) under the hood. That means findById() triggers findOne() middleware.
const schema = new mongoose.Schema({ _id: Number }, { versionKey: false });
schema.pre('findOne', function() {
console.log('Called `findOne()`');
});
const Model = mongoose.model('MyModel', schema);
await Model.create({ _id: 1 });
// Prints "Called `findOne()`" because `findById()` calls `findOne()`
await Model.findById(1);
Mongoose casts queries to match your schema. That means if your _id is a MongoDB ObjectId, you can pass the _id as a string and Mongoose will convert it to an ObjectId for you.
const _id = '5d273f9ed58f5e7093b549b0';
const schema = new mongoose.Schema({ _id: mongoose.ObjectId }, { versionKey: false });
const Model = mongoose.model('MyModel', schema);
await Model.create({ _id: new mongoose.Types.ObjectId(_id) });
typeof _id; // 'string'
// `{ _id: '5d273f9ed58f5e7093b549b0' }`
const doc = await Model.findById(_id);
typeof doc._id; // 'object'
doc._id instanceof mongoose.Types.ObjectId; // true
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