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How to update nested object in a MongoDB collection based on the request?

I've a collection for user given below
{
"_id": 1
"firstname": "John"
"lastname": "Doe"
"address": {
"street": "13",
"city": "Los Angeles",
"state": "California",
"country": "USA",
"pincode": "12345"
}
}
I want to make an API that will update the user data.
This is what I've tried:
First Method
Using this method some fields are being removed from collection which are not present in request.
Query:
const updateUser = (userId, data) => {
return UserDB.updateOne({ _id: userId }, {
$set: {...data }
});
};
Request:
{
"_id": 1
"firstname": "Justin"
"lastname": "Thomas"
"address": {
"country": "Canada",
"pincode": "9999"
}
}
Result:
// street, city and state is removed from collection
{
"_id": 1
"firstname": "Justin"
"lastname": "Thomas"
"address": {
"country": "Canada",
"pincode": "9999"
}
}
Second Method:
Using this method, fields are set to null which are not present in the request.
Query:
const updateUser = (userId, data) => {
return UserDB.updateOne({ _id: userId }, {
$set: {
"firstname": data.firstname,
"lastname": data.lastname,
"address.street": data.address.street,
"address.city": data.address.city,
"address.state": data.address.state,
"address.country": data.address.country,
"address.pincode": data.address.pincode
}
});
};
Request:
{
"_id": 1
"firstname": "Justin"
"lastname": "Thomas"
"address": {
"country": "Canada",
"pincode": "9999"
}
}
Result:
// street, city and state is set to null in the collection.
{
"_id": 1
"firstname": "Justin"
"lastname": "Thomas"
"address": {
"street": null,
"city": null,
"state": null,
"country": "Canada",
"pincode": "9999"
}
}
Question
How can I update a nested object in a collection?

Second method is working fine playground, please check your data.

Use $addFields in aggregation pipeline of update operation.
$addFields will only update the values that is present in the object and other fields will remain as it is.
Like this:
db.collection.update({
_id: 1
},
[
{
$addFields: {
"firstname": "Justin",
"lastname": "Thomas",
"address": {
"country": "Canada",
"pincode": "16565"
}
}
}
])
Test it here: https://mongoplayground.net/p/pjO8mIKb03o

Javascript function return False but should return True

I am checking for a condition and based on that returning true and false. The thing is my condition even satisfied. Below is my code
$scope.getPostalcode = function(obj) {
for ( var x in obj) {
if (typeof obj[x] === 'object') {
$scope.getPostalcode(obj[x]);
} else if (x === 'postalCode') {
if (obj.postalCode == $scope.postalCode) {
return true;
break;
}
}
}
return false;
}
The value of obj.postalCode and $scope.postalCode is same. Also I have checked the type of both is string. I am also including my object in case I am making the mistake there.
[
{
"account": "10066",
"pcn": "K770",
"msn": "6631",
"meterName": "DM",
"address": {
"companyName": "Test",
"street": "10 Downing Street",
"city": "LONDON",
"country": "UK",
"postalCode": "SW1A 2AA"
}
},
{
"account": "63350",
"pcn": "K7",
"msn": "663",
"meterName": "DM5",
"address": {
"companyName": "DITIQUE",
"street": "10 Downing Street",
"city": "LONDON",
"country": "UK",
"postalCode": "SW1A 2AA"
}
}
]

Remove identifiers from object

i have a object which has identifiers:
const cities = {
"0": {
"city": "Bielsko-Biała",
"country": "PL",
},
"1": {
"city": "Kielce",
"country": "PL",
},
"2": {
"city": "Kłodzko",
"country": "PL",
}
}
What i want is to remove 0, 1, 2 and so on to get this format:
const cities = [
{
"city": "Bielsko-Biała",
"country": "PL",
},
{
"city": "Kielce",
"country": "PL",
},
{
"city": "Kłodzko",
"country": "PL",
}
]
It is neccessary to me because i want to add description to every city and i couldn't map in this object because of that format.
I had to do something like that in React and i think it is a very bad written code:
const cities = [];
countries.map(el => {
cities.push(el.city)
})
let updatedCountries = countries;
cities.forEach((city) => {
axios.get(`https://en.wikipedia.org/api/rest_v1/page/summary/${city}`)
.then(response => {
for (let property in updatedCountries) {
if (updatedCountries.hasOwnProperty(property)) {
if (updatedCountries[property].city === city) {
updatedCountries[property]['description'] = response.data.description
}
}
}
})
})
this.setState({
countries: updatedCountries
})

You can use Object.values()
The Object.values() method returns an array of a given object's own enumerable property values,
const cities = {
"0": {
"city": "Bielsko-Biała",
"country": "PL",
},
"1": {
"city": "Kielce",
"country": "PL",
},
"2": {
"city": "Kłodzko",
"country": "PL",
}
}
let values = Object.values(cities);
console.log(values);

Fetch the no of of occurence in a array based on other key value

var json = [{
"city": "California",
"name": "Joe",
"age": 17,
"type",:"custom"
}, {
"city": "California",
"name": "Bob",
"age": 17,
"type",:"predefined"
}, {
"city": "California",
"name": "Bob",
"age": 35,
"type",:"custom"
}, {
"city": "Texas",
"name": "Bob",
"age": 35,
"type",:"custom"
}, {
"city": "Florida",
"name": "Bob",
"age": 35,
"type",:"predefined"
}];
I have above array and i have to construct object, based on "type" value i.e "predefined" or "custom" as below
updatedjson = {
"predefined": [{
"name": "California",
"count": 1
}, {
"name": "Florida",
"count": 1
}]
"custom": [{
"name": "California",
"count": 2
}, {
"name": "Texas",
"count": 1
}]
}
Any Approach using javascript or lodash

Using Lodash
var json = [{
"city": "California",
"name": "Joe",
"age": 17,
"type": "custom"
}, {
"city": "California",
"name": "Bob",
"age": 17,
"type": "predefined"
}, {
"city": "California",
"name": "Bob",
"age": 35,
"type": "custom"
}, {
"city": "Texas",
"name": "Bob",
"age": 35,
"type": "custom"
}, {
"city": "Florida",
"name": "Bob",
"age": 35,
"type": "predefined"
}];
// Solution to the problem
var updatedJson = _(json).groupBy("type").value(); // #1
_.forOwn(updatedJson, function(value, key) {
let countByCity = _(value).countBy('city').value(); // #2
let res = [];
_.forOwn(countByCity, function(value, key) {
res.push({ // #3
name: key,
count: value
});
});
updatedJson[key] = res;
});
console.log(updatedJson);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js"></script>
Explanation
Code first groups by type
Then counts by cities, within the group
Finally pushes the count object into an array, in the expected format

You can use reduce & findIndex
var json = [{
"city": "California",
"name": "Joe",
"age": 17,
"type": "custom"
}, {
"city": "California",
"name": "Bob",
"age": 17,
"type": "predefined"
}, {
"city": "California",
"name": "Bob",
"age": 35,
"type": "custom"
}, {
"city": "Texas",
"name": "Bob",
"age": 35,
"type": "custom"
}, {
"city": "Florida",
"name": "Bob",
"age": 35,
"type": "predefined"
}];
var updatedjson = json.reduce(function(result, item) {
// check if type is present in the object
// if not present then add a key by name custom/predefined
if (!result[item.type]) {
result[item.type] = [];
// add city name and intial count
result[item.type].push({
name: item.city,
count: 1
})
} else {
// now find the index of the object whe name matches with current city
let m = result[item.type].findIndex(function(obj) {
return obj.name === item.city
})
// if no matches then add the new object to either custom/predefined
if (m === -1) {
result[item.type].push({
name: item.city,
count: 1
})
} else {
// if matches then increase the value of count
result[item.type][m].count += 1
}
}
return result;
}, {});
console.log(updatedjson)

You can use array.reduce to create a new object with the aggregated data. Example:
const result = json.reduce((obj, data) => {
// if this is a new type, we must initialize it as an empty array and push the first record.
if(!obj[data.type]) {
obj[data.type] = [];
obj[data.type].push({name: data.city, count: 1});
return obj;
}
// else ... check if the current city is present in that type
const existingRecord = obj[data.type].find(d => d.name === data.city);
if(!existingRecord) {
// if the city is not present in that type, we initialize it with count 1
obj[data.type].push({name: data.city, count: 1});
return obj;
}
// if the city is present, we just update count = count + 1;
existingRecord.count++;
return obj;
}, { })
Now, you probably want to extract some of that logic into separate functions to increase readability. I don't think you need lodash for this but in the case you already have it included in your project then feel free to use it :P

Query JSON data sharing same value

Sample JSON Data:
{
"results": [
{
"name": "John Smith",
"state": "NY",
"phone": "555-555-1111"
},
{
"name": "Mary Jones",
"state": "PA",
"phone": "555-555-2222"
},
{
"name": "Edward Edwards",
"state": "NY",
"phone": "555-555-3333"
},
{
"name": "Abby Abberson",
"state": "RI",
"phone": "555-555-4444"
},
]}
With this sample data I can display individual values from the results [] array with object.name and object.phone to look something like:
John Smith 555-555-1111<br />
Mary Jones 555-555-2222<br />
Edward Edwards 555-555-3333<br />
Abby Abberson 555-555-4444
What I am trying to do now is select just the people who's state value is NY and only display their object.name and object.phone:
John Smith 555-555-1111<br />
Edward Edwards 555-555-3333
I tried this lovely little block but all it did was print all the names, which makes sense after I tried it.
if (object.state = "NY") {
div.append(repName);
}
I can't seem to think of a way to only display those that share a the same state.
I'm probably searching for the wrong terms or have to go about this another way... please help!

You are using =(assignment operator),which is wrong.
You have to use ==(comparison operator)
So do like below:-
if (object.state == "NY") {
div.append(repName);
}
Working sample-
var obj = {
"results": [
{
"name": "John Smith",
"state": "NY",
"phone": "555-555-1111"
},
{
"name": "Mary Jones",
"state": "PA",
"phone": "555-555-2222"
},
{
"name": "Edward Edwards",
"state": "NY",
"phone": "555-555-3333"
},
{
"name": "Abby Abberson",
"state": "RI",
"phone": "555-555-4444"
},
]};
$(obj.results).each(function(k,object){
if (object.state == "NY") {
$('#final_data').append(object.name +" : "+object.phone+"<br/>");
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="final_data"></div>

My one cent solution:
var obj = {
"results": [
{
"name": "John Smith",
"state": "NY",
"phone": "555-555-1111"
},
{
"name": "Mary Jones",
"state": "PA",
"phone": "555-555-2222"
},
{
"name": "Edward Edwards",
"state": "NY",
"phone": "555-555-3333"
},
{
"name": "Abby Abberson",
"state": "RI",
"phone": "555-555-4444"
},
]};
obj.results.forEach((value) => {
if (value.state === "NY") {
const li = document.createElement("li");
li.innerHTML = `${value.name} : ${value.phone}`;
document.querySelector("#final_data").appendChild(li);
}
});
<ul id="final_data"></ul>
Like Alive said you used the assignment operator = instead of comparison operator === or ==.