Access deep nested object from array - node.js

I am having a challenge getting just the username in a response below. How do I access the username. i can access the other data but this
[
{
"_id": "5f44d450aaa72313549d519f",
"imageTitle": "uuuuu",
"imageDesc": "uuuuu",
"imageControl": "public",
"imageUrl": "http://localhost:3000/uploads/image-1598346320523.jpg",
"userId": {
"local": {
"username": "uuuuu"
},
"_id": "5f44d3e9aaa72313549d519e"
},
"uploadedOn": "2020-08-25T09:05:20.840Z",
"__v": 0
},
{ ....}
]

You can do it like so
var arr = JSON.parse(`
[ { "_id": "5f44d450aaa72313549d519f", "imageTitle": "uuuuu", "imageDesc": "uuuuu", "imageControl": "public", "imageUrl": "http://localhost:3000/uploads/image-1598346320523.jpg", "userId": { "local": { "username": "uuuuu" }, "_id": "5f44d3e9aaa72313549d519e" }, "uploadedOn": "2020-08-25T09:05:20.840Z", "__v": 0 },
{}
]`);
console.log(arr[0].userId.local.username);
If you are on a newer version of node (14.0.0, and up), then I recommend using the optional chaining operator
arr[0].userId?.local?.username

Related

How to set up aggregation pipeline for specific use case in MongoDB

`I have two collections in MongoDB. One is users and the other is companies. I need to be able to populate the users.endpoints with the endpoints from companies that match ObjectID's which are in the user.endPoints property. It is a bit hard for me to wrap my head around considering there are two steps.
This is the companies collection.
{
"_id": {
"$oid": "63ed39162bfc2cf8065b76cf"
{
"_id": {
"$oid": "63ed39162bfc2cf8065b76cf"
},
"companyName": "Sowegatel",
"amount": 0,
"signalwireSid": "id",
"numbers": [
{
"number": "+12068133580",
"_id": {
"$oid": "63ed39c72bfc2cf8065b76f0"
},
"createdAt": {
"$date": {
"$numberLong": "1676491207931"
}
},
"updatedAt": {
"$date": {
"$numberLong": "1676491207931"
}
}
}
],
"endPoints": [
{
"userName": "4009",
"_id": "fb1d0ef9-c713-400e-a3c9-cbc6823aaf57"
},
{
"userName": "4019",
"_id": "506e710d-14a6-4345-bc89-8488af4cabe4"
},
{
"userName": "4020",
"_id": "c80bd1ab-ca8d-4649-9d35-56d64ef8fab5",
"type": "sip_endpoint"
}
],
"__v": 6
} },
"companyName": "Sowegatel",
"amount": 0,
"signalwireSid": "id",
"numbers": [
{
"number": "+12068133580",
"_id": {
"$oid": "63ed39c72bfc2cf8065b76f0"
},
"createdAt": {
"$date": {
"$numberLong": "1676491207931"
}
},
"updatedAt": {
"$date": {
"$numberLong": "1676491207931"
}
}
}
],
"endPoints": [
{
"userName": "4009",
"_id": "fb1d0ef9-c713-400e-a3c9-cbc6823aaf57"
},
{
"userName": "4019",
"_id": "506e710d-14a6-4345-bc89-8488af4cabe4"
},
{
"userName": "4020",
"_id": "c80bd1ab-ca8d-4649-9d35-56d64ef8fab5",
"type": "sip_endpoint"
}
],
"__v": 6
}
This is the users collection.
{
"_id": {
"$oid": "63ed39162bfc2cf8065b76d2"
},
"firstName": "mark",
"lastName": "thomas",
"email": "mt#st.com",
"password": "",
"companyId": {
"$oid": "63ed39162bfc2cf8065b76cf"
},
"active": true,
"role": "companyAdmin",
"tokens": [],
"__v": 2,
"endpoints": [
// I need to populate to endpoints here!!!! //
"c80bd1ab-ca8d-4649-9d35-56d64ef8fab5"
]
}
I can do a single step aggregation, but this is a little complicated for me.`

Joining only matching elements

I want to join more than two collections in MongoDB . Is it possible to join?
I have 2 collections and I want to join them based by their ids
news collection
{
"lang": "ru",
"news": [{
"title": "title",
"content": "desc",
"image": "path",
"categoryId": {
"$oid": "6171499e0ba3d75082823c9a"
},
"createdAt": {
"$date": "2021-10-21T12:30:33.215Z"
},
"_id": {
"$oid": "61715d7990905adefcf314d1"
}
}]
}
and I have got newscategory collection like that
[
{
"lang": "ru",
"categories": [{
"name": "sdfsdsdcsdf",
"_id": {
"$oid": "6171499e0ba3d75082823c9a"
}
}]
},
{
"lang": "en",
"categories": [{
"name": "ooo",
"_id": {
"$oid": "61712980f8ee795c6a569dcb"
}
}, {
"name": "yuy",
"_id": {
"$oid": "61712980f8ee795c6a569dcc"
}
}, {
"name": "rtyrty",
"_id": {
"$oid": "61712980f8ee795c6a569dcd"
}
}]
}
]
Expected Output:
[
{
"_id": "61715d7990905adefcf314d0",
"lang": "ru",
"news": [
{
"title": "sdf",
"content": "sdf",
"image": "asdas",
"categoryId": "6171499e0ba3d75082823c9a",
"caregory": [
{
"name": "sdfsdsdcsdf",
"_id": "6171499e0ba3d75082823c9a"
},
]
"createdAt": "2021-10-21T12:30:33.215Z",
"_id": "61715d7990905adefcf314d1"
}
],
Match is based on both "category_id" and "categories._id".
How can I achieve result like that ?

How to query nested object in mongodb

I'm new to mongodb and I've been trying to query this doc for awhile now.
Im trying to query all the rooms that have a room name of 100.
json
{
"count": 3,
"reviews": [
{
"_id": "5f9d42a0a8e71e004643f584",
"user": {
"_id": "5f7308cde0a4a7a66bc3d184",
"name": "Guest"
},
"room": {
"_id": "5f98f9321fd5bb0045b3d886",
"name": "100",
},
"rating": 4,
},
{
"_id": "5f9d431ea8e71e004643f585",
"user": {
"_id": "5f7308cde0a4a7a66bc3d184",
"name": "Guest",
},
"room": {
"_id": "5f98f9321fd5bb0045b3d886",
"name": "100",
},
"rating": 5,
},
{
"_id": "5f9e74fea6c06a0046d3cae2",
"user": {
"_id": "5f7308cde0a4a7a66bc3d184",
"name": "Guest",
},
"room": {
"_id": "5f98fa8b1fd5bb0045b3d88a",
"name": "300",
},
"rating": 5,
}
]}
what I've tried
1. find({},{"reviews.room.name": {$eq: "100"}}) // getting a projection error
2. find({"reviews.room.name": "100"}) // getting null
Any help to the right direction would be greatly appreciated.
Check out the docs about how to use find:
https://docs.mongodb.com/manual/reference/method/db.collection.find/
and try this
db.reviews.find({
"room.name": "100"
})
Here is the playground with your example: https://mongoplayground.net/p/dPfH5fSOePq
did u try this ? const response = await Room.find({name: "100"})

how to exclude value when certain property not exist in loopback

I'm getting below response from loopback when I filter with below api:
http://localhost:8001/myloopback/productDetails?q=product.productId==apple
I want to exclude the data which doesn't have property "productModel" - how can we achieve this in Loopback rest API. Is there any option to exclude property from the rest API query param? I'm new to Loopback - it would be really grateful if someone can help me to fix this
{
"myData": [{
"data": {
"product": {
"productId": "apple",
"productName": "iPhone",
"productModel": "6s"
},
"statusCode": "active",
"date": "2018-08-07T00:00:00.000Z"
},
"links": [{
"productUrl": "test"
},
{
"productImage": "test"
}
],
"info": {}
},
{
"data": {
"product": {
"productId": "apple",
"productName": "iPhone",
"productModel": "7"
},
"statusCode": "active",
"date": "2018-08-07T00:00:00.000Z"
},
"links": [{
"productUrl": "test"
},
{
"productImage": "test"
}
],
"info": {}
},
{
"data": {
"product": {
"productId": "apple",
"productName": "Macbook"
},
"statusCode": "active",
"date": "2018-08-07T00:00:00.000Z"
},
"links": [{
"productUrl": "test"
},
{
"productImage": "test"
}
],
"info": {}
}
],
"metadata": {
"count": 3,
"offset": 0
}
}
There is no such inbuilt function to do that but you can use multiple Fields filter to achieve that.

Query to retrieve every subdocument alone without passing parent id using Mongoose

Here i like to explain my problem.
How can i write a mongoose query to retrieve every subdocument from JSON without passing parent_id.
[
{
"_id": "56a320003fe17cc7363dd0d7",
"name": "Leanna Jacobson",
"gender": "female",
"friends": [
{
"id": 0,
"name": "Riley Case"
},
{
"id": 1,
"name": "Herman Carter"
},
{
"id": 2,
"name": "Pacheco Woodard"
}
]
},
{
"_id": "56a3200001501cfa1ea2641d",
"name": "Juliana Bonner",
"gender": "female",
"friends": [
{
"id": 0,
"name": "Keller Woodward"
},
{
"id": 1,
"name": "Fern Knight"
},
{
"id": 2,
"name": "Cain Richards"
}
]
},
{
"_id": "56a3200006864c78ecb1aeed",
"name": "Gena Stark",
"gender": "female",
"friends": [
{
"id": 0,
"name": "Kate Franco"
},
{
"id": 1,
"name": "Araceli Mcclure"
},
{
"id": 2,
"name": "Molly Nelson"
}
]
},
{
"_id": "56a320006d868155161038b6",
"name": "Eve Gonzalez",
"gender": "female",
"friends": [
{
"id": 0,
"name": "Pam Lang"
},
{
"id": 1,
"name": "Christy Marks"
},
{
"id": 2,
"name": "Donovan Warren"
}
]
},
{
"_id": "56a3200066b94852f5680568",
"name": "Coleman Wooten",
"gender": "male",
"friends": [
{
"id": 0,
"name": "Roberta Olson"
},
{
"id": 1,
"name": "Roseann Reid"
},
{
"id": 2,
"name": "Kerri Russell"
}
]
}
]
Here i need to retrieve every friends details from the subdocument array friends for every parent.
so how can i write query for this?????
Suppose the name of your schema is Person, try this one.
//find all document, only select `friends` field from every document
Person.find({}, 'friends', function (err, friends) {
// the return friends is the [[friends], [friends], ...]
});

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