find object inside JSON using nested ID - node.js

i have a mongo collection like this
{"stores": [{"name": "foo",
"songs": [ {"id": "", "name": "", "artist": "", "category": "", "tags": []} ],
"songsSchedule": [
{
"song_id": "",
"date": ,
"user": "",
"help": ,
"partners": [{"user": ""}],
"likes":
}
]
}]}
and i want to get the songs name and artist from the songsSchedule song_id, i've tried this but it's not working
var query = { _id: fn.generateID(req.params.store_id), songsSchedule: { $exists: true } };
var select = { songsSchedule:1 };
var array = [];
client("stores", function(err, collection) {
if (err)
return res.json(fn.status("30"));
collection.findOne(query, select, function(err, store) {
if (err || !store)
return res.json(fn.status("31"));
for (var i in store.songsSchedule) {
var song = store.songsSchedule[i];
array.push(song.song_id);
}
collection.find({ _id: fn.generateID(req.params.store_id), "songs._id": { $in: array } }, function(err, songs) {
res.json(songs);
});
});
});
and i dont really know if it's the best way of doing it

I'm not entirely clear what you mean by "get the songs name and artist from the songsSchedule song_id" but it looks like that query will be messy.
If it were me, I'd consider splitting out songs and songSchedule into their own collections for easier querying.

from your document example, the "songs" field contains documents that do not contain an "_id" field.
"songs": [ {"name": "", "artist": "", "category": "", "tags": []} ]
But, your find() query is querying on the "songs._id" field.
Also, I'm not too familiar with the json() method, but does it handle cursors?
Regards,
Kay

Related

PouchDB/CouchDB Group By Value in Array

I am using PouchDB and I have a dataset representing a social network in a graph. People are documents, and the people they follow are in an array of the _id of the person followed. Here is a sample of the data:
[
{
"_id": "mc0001",
"name": "Jill Martin",
"joined": "2020-01-15",
"follows": []
},
{
"_id": "mc0002",
"name": "Elena Markova",
"joined": "2020-01-21",
"follows": ["mc0001"]
},
{
"_id": "mc0003",
"name": "Carlos Sanchez",
"joined": "2020-01-27",
"follows": ["mc0001", "mc0002"]
},
{
"_id": "mc0004",
"name": "Ai Sato",
"joined": "2020-02-21",
"follows": ["mc0001", "mc0003"]
},
{
"_id": "mc0005",
"name": "Ming Wu",
"joined": "2020-03-21",
"follows": ["mc0002", "mc0003", "mc0004"]
}
]
What I would like to do is query for each person, and get a list of followers. I am looking for something like this:
[
{
"_id": "mc0001",
"followers": ["mc0002", "mc0003", "mc0004"]
},
{
"_id": "mc0002",
"followers": ["mc0003", "mc0005"]
},
{
"_id": "mc0003",
"followers": ["mc0004", "mc0005"]
},
{
"_id": "mc0004",
"followers": ["mc0005"]
},
{
"_id": "mc0005",
"followers": []
}
]
Is there a way to do this without changing the data structure (e.g. moving the followers array into the doc of the person being followed)?
Create a Map/Reduce view that loops through the follows array in each document and emits those; like this:
function (doc) {
for(var i =0; i<doc.follows.length; i++) {
emit(doc.follows[i], null);
}
}
You end up with an index keyed on a user and where each row has the id of a follower of that user. You can then query the index, supplying the key of the user whose followers you want to find, like this:
$URL/users/_design/users/_view/by-follower?key="mc0001"&reduce=false
You will get something like this:
{"total_rows":8,"offset":0,"rows":[
{"id":"mc0002","key":"mc0001","value":null},
{"id":"mc0003","key":"mc0001","value":null},
{"id":"mc0004","key":"mc0001","value":null}
]}
This is not exactly the format of the data you have in your question, but you can see that the id field in each object contains a follower of your desired user, so you can go from there.

MongoDb find all objects that contain nested value

This is my user object sent as token in req:
{
"_id": "6212aba16653621e67393549c",
"name": "User",
"email": "user#gmail.com",
"__v": 0
}
This is my get function code:
const getSharedLists = asyncHandler(async (req, res) => {
const lists = await List.find({
sharedWith: { email: req.user.email },
});
res.status(200).json(lists);
});
This is what object looks like:
{
"_id": "621817233300dfff68e23710",
"user": "6212ab33383621e67393549c",
"listName": "test update",
"private": true,
"items": [
{
"itemName": "Bananas",
"quantity": 3,
"isBought": false,
"isle": "isle",
"_id": "621b043622147906eece2e72"
},
],
"sharedWith": [
{
"email": "user#gmail.com",
"_id": "621bdbf0791a322534284c49"
}
],
"createdAt": "2022-02-24T23:39:25.668Z",
"updatedAt": "2022-02-27T21:21:03.584Z",
"__v": 0,
},
I keep getting empty array back, even when hard code req.user.email as "user#gmail.com" for example. I need to find all lists on MongoDb that have my email in array of sharedWith.
Can somebody help please. Apparently I'm using List.find method wrong but can't seem to figure out the syntax.
You need (.) dot notation.
const lists = await List.find({
"sharedWith.email" : req.user.email
});
Sample Mongo Playground
Reference
Specify a Query Condition on a Field Embedded in an Array of Documents

How to update a value inside mongodb with nodeJS?

I'm trying to update a value inside mogoodb array but is the problem
database?
"TempChannels": [{
"user": "299481590445113345",
"channel": "794869948878159884",
"settings": []
}, {
"user": "583363766750806043",
"channel": "795004103998308352",
"settings": []
}],
The part of the code that should update the user:
Data.TempChannels[0].user = Target.id
Data.save().catch(er => console.log(er))
Also, no error appears when I run the code. and when i console the data it returns a user which has updated but it is not actually saved in mongodb!
code
Data.save().then(() => console.log(Data.TempChannels[0].user))
this is the whole data
{
"_id": {
"$oid": "5ff0cd1ee3d9fd2d40d82d23"
},
"TempChannels": [{
"user": "299481590445113345",
"channel": "795014692522295326",
"settings": []
}, {
"user": "583363766750806043",
"channel": "795015273060892753",
"settings": []
}],
"Guild": "704158258201624657",
"Stats": "true",
"ChannelID": "795014681664290826",
"ParentID": "795014680556994610",
"LogChannelID": "795014683601010709",
"TempControlChannelID": "795014682518749274",
"DefaultSettings": {
"limit": null,
"name": null,
"bitrate": null,
"copyperms": null
},
"__v": 2
}
I'm filtering the data by Guild
if you are using mongoose to connect MongoDB, the
Use markModified("updated field name")
Data.TempChannels[0].user = Target.id
Data.markModified('TempChannels');
Data.save().catch(er => console.log(er))
if you are using mongoose, there is a method that will allow to update the content of existing data
const res = await Person.replaceOne({ _id: 24601 }, { name: 'Jean Valjean' });
res.n; // Number of documents matched
res.nModified; // Number of documents modified
If you are using Mongoose, you can update the record by doing something similar to this:
SchemaName.update({Guild: 'Guild Value Here'}, {$set: { "TempChannels[0].user" : "%newvalue%"}})
.then((data) => {
console.log(data)
})
.catch(err => {
console.log.error(err);
});
You should replace schemaName with the name of your schema if you are using mongoose, and in case you are not using it, I think it would be better for you to start using it.

Multiple conditions in updateOne query in mongodb

Document in mongodb collection 'users' is
{
"$oid": "5e612272bcb362513824ff9b",
"name": "abcd",
"email": "test#test.com",
"cart": {
"items": [{
"productId": {
"$oid": "5e614367cae25319c4388288"
},
"quantity": {
"$numberInt": "1"
}
}]
}
}
For a particular users._id and a productId in cart.items, I need to increase the quantity by 1
My nodejs code is
IncrCartItem(prodId){
const db=getDb()
return db
.collection('users').
updateOne({_id: new mongodb.ObjectId(this._id),'this.cart.items.productId': new mongodb.ObjectId(prodId)},{$inc : {'this.cart.items.quantity':1}})
}
Is the query right for checking multiple conditions in updateOne()??
You're kinda there, to "and" them all together you just keep appending them, however the field is wrong and you need to use the positional operator ($) - https://docs.mongodb.com/manual/reference/operator/update/positional/
const filter = {
_id: new mongodb.ObjectId(this._id),
'cart.items.productId': new mongodb.ObjectId(prodId)
};
const update = {
$inc : { 'this.cart.items.$.quantity': 1 }
};
IncrCartItem(prodId){
const db=getDb()
return db
.collection('users').
updateOne(filter,update)
}

Mongoose: Update does not work in nested array object

I have a document with the array of objects and one object contains multiple objects I want to update inner object with $set but didn't get any luck.
can anybody give me any hint so that I can resolve it?.
This is my object:
{
"_id": ObjectId("56fbfafdf86fa6161911d104"),
"site": "xyz",
"adsPerCategory": NumberInt(2),
"sampledAt": ISODate("2016-03-30T16:12:45.138+0000"),
"items": [
{
"id": "4563873",
"content": {
"title": "WATER DISTILLERS",
"body": "Perfect to save money.",
}
},
{
"id": "4563s23232873",
"content": {
"title": "Cola water",
"body": "Perfect for body.",
}
}
]
}
I want to update body.
for now, I have given single object but it can be multiple.
Here what I tried
models.Sample.update(
{
_id: samples._id
},
'$set': {
'items.0.content.body': body.description
},
function(err, numAffected) {
console.log(err);
console.log('Affected....', numAffected);
}
);
It's working fine if I put 0 but I want to make it dynamic.
Like 'items.index.content.body': body.description
Thank You.
I think you can do something like this.
models.Sample.find({ _id: ObjectId(samples._id) })
.forEach(function (doc) {
doc.items.forEach(function (element, index, array) {
items[index].content.body = body.description;
});
models.Sample.save(doc);
});

Resources