I need to change a few database fields in my backend controller before returning the object to the frontend.
Currently, I am doing it in the front end like this with my returned object:
for (let contribution of contributions) {
contribution["title"] = "You Added One"
contribution["launchName"] = contribution.name
contribution["launchId"] = contribution._id
contribution["date"] = contribution.addedAt
contribution["content"] = contribution.description
}
But I am now trying to do this work in the backend using Mongo.
This is my controller:
const Launch = require('../models/launch')
const User = require('../models/user')
async function getRecentActivityByUserId (req, res) {
const { userId } = req.params
const user = await User.findOne({ userId }).lean() || []
const contributions = await Launch.find({ _id: { $in: user.contributions } })
return res.status(200).send(contributions.reverse())
}
So this correctly returns an object to the frontend but I still need to change the database field names.
So I tried this:
async function getRecentActivityByUserId (req, res) {
let recents = []
const { userId } = req.params
const user = await User.findOne({ userId }).lean() || []
const contributions = await Launch.find({ _id: { $in: user.contributions } }).aggregate([
{
$addFields: {
plans: {
$map:{
input: "$launch",
as: "l",
in: {
title: "You Added One",
launchName: "$$l.name",
launchId: "$$l._id",
date: "$$l.addedAt",
content: "$$l.description",
}
}
}
}
},
{
$out: "launch"
}
])
return res.status(200).send(contributions.reverse())
}
The above throws an error saying that I .aggregrate is not a function on .find. Even if I remove the .find, the object returned is just an empty array so I'm obviously not aggregating correctly.
How can I combine .find with .aggregate and what is wrong with my .aggregate function??
I also tried combining aggregate with find like this and get the error Arguments must be aggregate pipeline operators:
const contributions = await Launch.aggregate([
{
$match: {
_id: { $in: user.contributions }
},
$addFields: {
plans: {
$map:{
input: "$launch",
as: "l",
in: {
title: "You Added a Kayak Launch",
launchName: "$$l.name",
launchId: "$$l._id",
date: "$$l.addedAt",
content: "$$l.description",
}
}
}
}
},
{
$out: "launch"
}
])
EDIT: Just realized that I have the word plans in the aggregate function and that is not relevant to my code. I copied this code from elsewhere so not sure what the value should be.
I figured it out. This is the solution:
async function getRecentActivityByUserId (req, res) {
let recents = []
const { userId } = req.params
const user = await User.findOne({ userId }).lean() || []
const contributions = await Launch.aggregate([
{
$match: {
_id: { $in: user.contributions }
}
},
{
$addFields: {
title: "You Added One" ,
launchName: "$name",
launchId: "$_id",
date: "$addedAt",
content: "$description"
}
}
])
if(contributions) {
recents = recents.concat(contributions);
}
return res.status(200).send(recents.reverse())
}
The actual problem from the question was a small syntax error which has been noted and corrected in the self-reported answer here.
I noted in the comments there that the current approach of issuing two separate operations (a findOne() followed by an aggregate() that uses the results) could be simplified into a single query to the database. The important thing here is that you will $match against the first collection (users or whatever the collection name is in your environment) and then use $lookup to perform the "match" against the subsequent launches collection.
Here is a playground demonstrating the basic approach. Adjust as needed to the specifics of your environment.
Related
I'm just trying to upsert a key value pair i.e. {mark : done} to my Mongo database using id that I have stored in an array.
But for the life of me I can't figure out why if I use a for loop it works fine. But if I use a forEach loop, it gives me a "Cannot use a session that has ended" Error.
I'm hoping someone SO assist in explaining why this happens
Boiler Plate Code
import { MongoClient } from "mongodb";
const uri = "mongodb://localhost:27018/";
const client = new MongoClient(uri);
Function with "for loop" implementation
async function updateMongo1() {
const db = client.db("testDB");
const coll = db.collection("testCollection");
await client.connect();
try {
let array = [
"2021-10-18",
"2021-10-17",
"2021-10-16",
"2021-10-15",
"2021-10-14",
];
for (let i = 0; i < array.length; i++) {
await coll.updateOne(
{ _id: array[i] },
{ $set: { mark: "done" } },
{ upsert: true }
);
}
} catch (e) {
console.error(e.message);
} finally {
await client.close();
}
}
Function with "forEach" implementation
async function updateMongo2() {
const db = client.db("testDB");
const coll = db.collection("testCollection");
await client.connect();
try {
let array = [
"2021-10-18",
"2021-10-17",
"2021-10-16",
"2021-10-15",
"2021-10-14",
];
array.forEach(async (element) => {
await coll.updateOne(
{ _id: element },
{ $set: { mark: "done" } },
{ upsert: true }
);
});
} catch (e) {
console.error(e.message);
} finally {
await client.close();
}
}
running different implementations yields different results.
(async () => {
//await updateMongo1(); //-> this works
await updateMongo2(); //-> this gives "MongoExpiredSessionError: Cannot use a session that has ended" what gives??
})();
Please let me know why this happens?
The element variable is an array e.g. ["2021-10-18"]. In the second implementation, you were meant to access element[0] but forgot to so you put an array into the _id field.
I don't know if that's what's specifically causing your error but it is an error in the implementation.
I am new to the javascript promise world and i wrote a code that updates my database table based on some params. but i want all these changes to be made at the same time, and i did some research and came across promise.all promise api. and i wanted to know what i was doing wrong or is there a better way to do this?
your help will be most appreciated.
promise code:
try {
syncEntities = async () => {
let saveTakerOrder;
let tradePromises;
// if no makers in the trade or the taker was not completely filled put it in the orders table
saveTakerOrder = await dynamodb
.put({
TableName: process.env.ORDERS_TABLE_NAME,
Item:
makers.length === 0 ||
taker.initial_quantity !== taker.quantity_removed
? taker
: {
...taker,
status: "CLOSED",
orderRate: `${taker.side}#CLOSED#${taker.rate}`,
},
})
.promise();
// if makers exist
if (makers.length > 0) {
tradePromises = makers.map(async (maker) => {
let savedTrade;
let updatedOrder;
// trade entity model
const matchedTrade = {
id: `TRD${uuid()}`,
buy_order: taker.side === "BUY" ? taker.id : maker.id,
sell_order: taker.side === "SELL" ? taker.id : maker.id,
ticker: maker.ticker,
rate: maker.rate,
quantity: maker.quantity_removed,
createdAt: date.toISOString(),
};
// Save the trade to the trades table
savedTrade = await dynamodb
.put({
TableName: process.env.TRADES_TABLE_NAME,
Item: matchedTrade,
})
.promise();
// Update the order in the orders table if quantity is not filled ELSE close it if completely filled
if (maker.quantity_removed !== maker.initial_quantity) {
updatedOrder = await dynamodb
.update({
TableName: process.env.ORDERS_TABLE_NAME,
key: { id: maker.id },
UpdateExpression:
"set quantity_removed = :quantity_removed, quantity_remaining = :quantity_remaining",
ExpressionAttributeValues: {
":quantity_remaining": maker.quantity_remaining,
":quantity_removed": maker.quantity_removed,
},
})
.promise();
} else {
updatedOrder = await dynamodb
.update({
TableName: process.env.ORDERS_TABLE_NAME,
Key: { id: maker.id },
UpdateExpression: "set #status = :status, orderRate = :orderRate",
ExpressionAttributeValues: {
":status": "CLOSED",
orderRate: `${maker.side}#CLOSED#${maker.rate}`,
},
ExpressionAttributeNames: {
"#status": "status",
},
})
.promise();
}
return Promise.all([savedTrade, updatedOrder]);
});
}
return Promise.all([tradePromises, saveTakerOrder]);
};
await Promise.all([syncEntities]);
} catch (error) {
console.error(error);
throw new createError.InternalServerError(error);
}
Please can someone point out what i am doing wrong with this code or help me correct it Thanks?
All you need to do is remove the awaits from the calls to the things you want to include in your Promise.all. The moment you await something it is going to resolve the promise before continuing. If you were to look at the object you get back from await dynamodb.update(...).promise(), for example, you'll notice that you have a DynamoDBUpdateResponse object (at least I think that's the type). But if you remove the await you'd have a Promise<DynamoDBUpdateResponse> object.
You can still get at the results of the promises after you call await Promise.all. Each item in the array will have a record in the resulting array.
I have this request:
// PUT that updates a user.
router.put('/api/user/:id', async (req: Request, res: Response) => {
const { email, name, avatar } = req.body
const userId = req.body._id
const conditions = {
_id : userId
}
const user = {$set: { "email": email, "name": name, "avatar": avatar } }
User.updateOne(conditions, user).then(doc => {
if (!doc) { return res.status(404).end() }
return res.status(200).json(doc)
}).catch(error => console.log(error))
})
And I get this response from the request:
{
"n": 0,
"nModified": 0,
"ok": 1
}
If you can find it on StackOverflow about the updateOne() method in mongoose I've probably tried it. The document isn't updating no matter what I try.
Edit: I've tried using an ObjectID in the query instead and the same result.
Edit 2: I figured it out. Was using req.body.id instead of req.params.id and I was using parameters to send the request. Thanks everyone for the help!
nModified == 0 implies that you have no user matching this id,
your route is put /api/user/:id but your user id is in req.params.id and not in req.body._id
A couple tips:
Try running the same query from mongodb at the command line, see if you get any results.
Is the "campaign_id" defined as an ObjectId in your schema? If so, try searching using the ObjectId type.
Try to change the query to :
const ObjectId = require('mongoose').Types.ObjectId;
const conditions = {
_id : new ObjectId(userId)
}
The reason for not updating is - mongoose is unable to search the with the id you provided.
if you want to update a document based on _id you can use findByIdAndUpdate()
const userId = req.body._id;
const user = { "email": email, "name": name, "avatar": avatar }
User.findByIdAndUpdate(userId , user,
function (err, docs) {
if (err){
console.log(err)
}
else{
console.log("Updated User : ", docs);
}
});
In case you've set your DB to strict mode don't forget to add strict:false in options when adding new keys. Otherwise, inserts will be silently ignored. I've just spent 2 hours wondering why my inserts don't get saved in DB despite not throwing any error.
See dos
http://mongoosejs.com/docs/guide.html#strict
const conditions = {
_id
}
const dateToUpdate = {
$set: {
"email": "email",
"name": "name",
"avatar": "avatar"
}
}
const updateRecord = await models.pdDealModel.updateOne(conditions,dateToUpdate,{
upsert:false,
strict:false
}
)
i can not able to update nested data in my mongodb. here is my "update" module at back-end side.
exports.updateOne = (req, res) => {
if (!req.body) {
return res.status(400).send({
message: "Data to update can not be empty!"
});
}
const {id} = req.params;
console.log(req.body);
User.findByIdAndUpdate(id, req.body, { useFindAndModify: false, new: true}).populate('basic')
.then(data => {
if (!data) {
res.status(404).send({
message: `Cannot update User with id=${id}. Maybe User was not found!`
});
} else
res.send({ message: "User was dupdated successfully." , data});
})
.catch(err => {
res.status(500).send({
message:
err.message || "Error updating User with id=" + id
});
});
};
and my front-end side is;
onChangePosition(e) {
const position = e.target.value;
this.setState(prevState => ({
currentStaff: {
...prevState.currentStaff,
basic:
{
...prevState.currentStaff.basic,
position:position
}
}
}));
}
onChangeEmail(e) {
const emailBusiness = e.target.value;
this.setState(prevState => ({
currentStaff: {
...prevState.currentStaff,
emailBusiness:emailBusiness
}
}));
}
updateStaff() {
StaffDataService.updateOne(
this.state.currentStaff.id,
this.state.currentStaff
).then(response => {
console.log(response.data);
})
.catch(e => {
console.log(e);
})
}
i can change state properly, and my sending data "req.body" is what i want (it is an object). There is no problem.
as you see above, i can update "email" because it is on the main body of object, but can not update "position" (nested element) because it is inside of basic (populated data).
i tried different methods by mongoose, and tried "$set" command.
Can anyone solve this?
To update, the nested value/object in your document, you should use dot notations, so it depends from the req.body variable value.
req.body shouldn't be a Mongoose doc. In such case you mongoose.toObject.
Second thing is:
[update] Object should be: field_with_subdocument.key_value: updated_propery
like this:
/** Example doc */
{
_id: 1,
parent_field: {
baby_field: value
}
}
/** Inside async function */
...await Model.findByIdAndUpdate(id, { "parent_field.baby_field": value })
Also, take a look at [`{overwrite: true}`](https://mongoosejs.com/docs/api/model.html#model_Model.findByIdAndUpdate) option. It might be useful to you.
I faced the same issue, In my case, the defined mongoose schema for that model did not match the nested Object I was passing to the findByIdAndUpdate method. let me simplify it, here is the model
import { model, Schema } from 'mongooose';
const UserModel = model('user', new Schema({
profile: {
avatar: String,
bio: String,
}
}));
And here is the update query:
async function getDefaultProfile() {
const user = await UserModel.findById(process.env.DEFAULT_USER);
return user.profile;
}
const profile = await getDefaultProfile();
UserModel.findByIdAndUpdate('user id', {
$set: {
profile: profile
}
});
The important note was that my getDefaultProfile function returns a mongoose nested object, not a pure object. So in the returned object, I had $set, $get, etc function. So as you know this object is not what we define in the mongoose model, therefore the mongoose ignores it.
So I guess you have the same problem, or something close to my issue.
What should I do?
Run your project in debugging mode.
then check req.body or whatever that gives you the nested object (in my case getDefaultProfile).
Check it with your model, Are they equal?
And if that solution does not work for you, please try this solution, write a utility function:
export async function flatObjectAndSeparateThemByDot(
object: any,
): Promise<any> {
const res: any = {};
(function recurse(obj: any, current?: string) {
for (const key in obj) {
const value = obj[key];
// joined keys with dot
const newKey = current ? current + '.' + key : key;
if (value && typeof value === 'object') {
// it's a nested object, so do it again
recurse(value, newKey);
} else {
// it's not an object, so set the property
res[newKey] = value;
}
}
})(object);
return res;
}
then you can pass your nested object to this function and you will get something like this: { "profile.avatar": "lorem ipsum", "profile.bio": "bio temp" }. So to show you how this function works I will write a sample code:
const sampleProfile = {
profile: {
avatar: "asd",
bio: "sample"
}
}
const profile = await flatObjectAndSeparateThemByDot(sampleProfile);
await UserModel.findByIdAndUpdate('user id', {
$set: {
// other fields,
...profile
}
});
I am building a website using Node.js and Sequelize (with a Postgres backend). I have a query that returns many objects with a foreign key, and I want to pass to the view a list of the objects that the foreign key references.
In the example, Attendances contains Hackathon keys, and I want to return a list of hackathons. Since the code is async, the following thing of course does not work in Node:
models.Attendance.findAll({
where: {
UserId: req.user.id
}
}).then(function (data) {
var hacks = [];
for (var d in data) {
models.Hackathon.findOne({
where: {
id: data[d].id
}
}).then(function (data1) {
hacks.append(data1);
});
}
res.render('dashboard/index.ejs', {title: 'My Hackathons', user: req.user, hacks: hacks});
});
Is there any way to do that query in a synchronous way, meaning that I don't return the view untill I have the "hacks" list filled with all the objects?
Thanks!
Use Promise.all to execute all of your queries then call the next function.
models.Attendance.findAll({
where: {
UserId: req.user.id
}
}).then(function (data) {
// get an array of the data keys, (not sure if you need to do this)
// it is unclear whether data is an object of users or an array. I assume
// it's an object as you used a `for in` loop
const keys = Object.keys(data)
// map the data keys to [Promise(query), Promise(query), {...}]
const hacks = keys.map((d) => {
return models.Hackathon.findOne({
where: {
id: data[d].id
}
})
})
// user Promise.all to resolve all of the promises asynchronously
Promise.all(hacks)
// this will be called once all promises have resolved so
// you can modify your data. it will be an array of the returned values
.then((users) => {
const [user1, user2, {...}] = users
res.render('dashboard/index.ejs', {
title: 'My Hackathons',
user: req.user,
hacks: users
});
})
});
The Sequelize library has the include parameter which merges models in one call. Adjust your where statement to bring the Hackathons model into Attendance. If this does not work, take the necessary time to setup Sequelize correctly, their documentation is constantly being improved. In the end, you'll save loads of time by reducing error and making your code readable for other programmers.
Look how much cleaner this can be...
models.Attendance.findAll({
include: [{
model: Hackathon,
as: 'hackathon'
},
where: {
UserId: req.user.id
}
}).then(function (data) {
// hackathon id
console.log(data.hackathon.id)
// attendance id
console.log(data.id)
})
Also..
Hackathon.belongsTo(Attendance)
Attendance.hasMany(Hackathon)
sequelize.sync().then(() => {
// this is where we continue ...
})
Learn more about Sequelize includes here:
http://docs.sequelizejs.com/en/latest/docs/models-usage/
Immediately invoke asynchronous function expression
This is one of the techniques mentioned at: How can I use async/await at the top level? Toplevel await is likely coming soon as of 2021, which will be even better.
Minimal runnable example:
const assert = require('assert');
const { Sequelize, DataTypes } = require('sequelize');
const sequelize = new Sequelize({
dialect: 'sqlite',
storage: 'db.sqlite',
});
const IntegerNames = sequelize.define(
'IntegerNames', {
value: { type: DataTypes.INTEGER, allowNull: false },
name: { type: DataTypes.STRING, },
}, {});
(async () => {
await IntegerNames.sync({force: true})
await IntegerNames.create({value: 2, name: 'two'});
await IntegerNames.create({value: 3, name: 'three'});
await IntegerNames.create({value: 5, name: 'five'});
// Fill array.
let integerNames = [];
integerNames.push(await IntegerNames.findOne({
where: {value: 2}
}));
integerNames.push(await IntegerNames.findOne({
where: {value: 3}
}));
// Use array.
assert(integerNames[0].name === 'two');
assert(integerNames[1].name === 'three');
await sequelize.close();
})();
Tested on Node v14.16.0, sequelize 6.6.2, seqlite3 5.0.2, Ubuntu 20.10.