We Keep Coding

How to find data on MongoDB by passing part of array objects

I tried to create an API for filtering the products by sending an array of objects as filters.
this is my Product schema:
const mongoose = require("mongoose");
const { s, rs, rn, rref, ref } = require("../utils/mongo");
let schema = new mongoose.Schema(
{
user: rref("user"),
name: rs,
description: s,
images: [s],
price: rn,
category: ref("category"),
filters: [
{
parent: ref("filter"),
value: s,
name: s,
},
],
subFilter: [
{
parent: s,
value: s,
title: s,
},
],
},
{ timestamps: true }
);
module.exports = mongoose.model("product", schema);
and this one is what I want to send as body to the API
{
category: '62445c3d922d127512867245'
filters: [
{ name: 'filter name 1', value: '62445c3d922d127512861236' },
{ name: 'filter name 2', value: '62445c3d922d127512861458' },
.....
]
}
as you see I want to filter my products based on category Id and an array of filter objects. I tried to write this query but it return an empty array.
this is my query:
filter: async (req, res) => {
try {
const { category, filters } = req.body;
const products = await Product.find({
category,
filters: {
$in: filters,
},
});
res.status(200).json(products);
} catch (err) {
res.status(500).json(err);
}
},
what stored on db
{
"_id" : ObjectId("62643acf19636d7db1804cb3"),
"images" : [
"image-1650735823476۸.jpg"
],
"user" : ObjectId("622606af0f40cb8ea37383dc"),
"name" : "شیر توپی 2 اینچ کلاس 150 پیشگام",
"description" : " برند پیشگام با مدارک و تاییدیه ",
"price" : NumberInt(5000000),
"category" : ObjectId("62445c4d922d127512867246"),
"filters" : [
{
"_id" : ObjectId("62643acf19636d7db1804cb4"),
"parent" : ObjectId("6264307f19636d7db1804b77"),
"value" : "626430bb19636d7db1804b78",
"name" : "Valve Type"
},
{
"_id" : ObjectId("62643acf19636d7db1804cb5"),
"parent" : ObjectId("6264319819636d7db1804b7b"),
"value" : "6264319819636d7db1804b7e",
"name" : "Body Type"
},
{
"_id" : ObjectId("62643acf19636d7db1804cb6"),
"parent" : ObjectId("626431ef19636d7db1804b82"),
"value" : "626431ef19636d7db1804b83",
"name" : "Bore Type"
},
{
"_id" : ObjectId("62643acf19636d7db1804cb7"),
"parent" : ObjectId("6264328519636d7db1804b85"),
"value" : "6264328519636d7db1804b86",
"name" : "Material Type"
},
{
"_id" : ObjectId("62643acf19636d7db1804cb8"),
"parent" : ObjectId("626435de19636d7db1804c10"),
"value" : "626439b619636d7db1804ca7",
"name" : "Trim Material"
},
{
"_id" : ObjectId("62643acf19636d7db1804cb9"),
"parent" : ObjectId("6264367919636d7db1804c17"),
"value" : "6264367919636d7db1804c18",
"name" : "End Conection"
},
{
"_id" : ObjectId("62643acf19636d7db1804cba"),
"parent" : ObjectId("626436a719636d7db1804c1f"),
"value" : "6264378119636d7db1804c28",
"name" : "Size"
},
{
"_id" : ObjectId("62643acf19636d7db1804cbb"),
"parent" : ObjectId("6264389219636d7db1804c6d"),
"value" : "6264389219636d7db1804c6f",
"name" : "Class / Pressure"
}
],
"subFilter" : [
{
"_id" : ObjectId("62643acf19636d7db1804cbc"),
"parent" : "6264328519636d7db1804b85",
"value" : "626433b919636d7db1804b93",
"title" : "Body Material"
}
],
"createdAt" : ISODate("2022-04-23T17:43:43.421+0000"),
"updatedAt" : ISODate("2022-04-23T17:53:29.016+0000"),
"__v" : NumberInt(0)
}

Consider this shrunk down set of inputs that capture the essence of the question. The comments "give away" what we are going to try to find and why. We only show one value for category because matching on that is trivial and not the interesting part of the query.
[
{
"category" : ObjectId("62445c4d922d127512867246"),
"filters" : [
// Matching Valve/value; include this doc
{"name" : "Valve", "value" : "626430bb19636d7db1804b78"},
// ALSO match Body/value; include this doc (but needs only 1 match)
{"name" : "Body", "value" : "6264319819636d7db1804b7e"}
]
}
,{
"category" : ObjectId("62445c4d922d127512867246"),
"filters" : [
// Not target value for Valve name (..79 instead of ...78):
{"name" : "Valve", "value" : "626430bb19636d7db1804b79"},
// ...but correct value for Body, so include this doc
{"name" : "Body", "value" : "6264319819636d7db1804b7e"}
]
}
,{
"category" : ObjectId("62445c4d922d127512867246"),
// No matching Valve or Body so this whole doc is ignored.
"filters" : [
{"name" : "Valve", "value" : "626430bb19636d7db1804b79"},
{"name" : "Body", "value" : "6264319819636d7db1804b7f"}
]
}
,{
"category" : ObjectId("62445c4d922d127512867246"),
// Not even name matches so ignore this too:
"filters" : [
{"name" : "Pipe", "value" : "6264319819636d7db1804eee"}
]
}
]
Assume also we set up inputs coming from the API like this, in their native form i.e. strings NOT ObjectId:
var targ_cat = '62445c4d922d127512867246';
var any_one_of = [
{ name: 'Valve', value: '626430bb19636d7db1804b78' },
{ name: 'Body', value: '6264319819636d7db1804b7e'}
];
We will use $filter as our main function but to do so, we must convert the incoming material into a form required by $filter.
// Convert inbound array of any_one_of into a something designed to work
// in the $filter function by comparing each name/value entry in the
// filters field to the item presented in $$this, meaning take:
// { name: 'Valve', value: '626430bb19636d7db1804b78' },
// and turn it into:
// {$and: [ {$eq:['Valve','$$this.name']}, {$eq:['62643...','$$this.value']} ] }
// Since any one of the entries is considered a hit, we package it all
// into an $or wrapper, not $and.
var or_list = [];
any_one_of.forEach(function(f) {
or_list.push( {$and: [
{$eq:[f['name'], '$$this.name']},
{$eq:[f['value'], '$$this.value']}
]});
});
var or_expr = {$or: or_list};
Now we are ready to query mongoDB:
db.foo.aggregate([
// Get this out of the way quickly; note we must make a new ObjectId!
{$match: {'category': new ObjectId(targ_cat)}}
// The interesting part of the query:
,{$addFields: {filters: {$filter: {input: '$filters', cond: or_expr}}}}
// Only keep those items where $filter found at least one of the
// targets:
,{$match: {$expr: {$gt:[{$size: '$filters'},0]} }}
]);

How to extract data from Firebase realtime database JSON-export

I have a Firebase realtime-database export-json that has nested informations, that I would like to extract. The structure of the JSON looks like this:
{
"users" : {
"024w97mv8NftGFY8THfQIU6PhaJ3" : {
"email" : "xxx",
"id" : "024w97mv8NftGFY8THfQIU6PhaJ3",
"name" : "xxx",
"items" : {
"-LQL9n-r9BGdo3HJZ2sk" : {
"disliked" : true,
"id" : 396,
"name" : "Aaa"
},
"-LQL9oO63nH-QW2w6zz0" : {
"liked" : true,
"id" : 3674,
"name" : "Bbb"
}
}
},
"0ERLT5DLRvbZUnjlnM7Ow0qItpz2" : {
"email" : "zzz",
"id" : "0ERLT5DLRvbZUnjlnM7Ow0qItpz2",
"name" : "zzz",
"items" : {
"-LIZnriSVQMzqTsPFNYa" : {
"id" : 396,
"liked" : true,
"name" : "Aaa"
},
"-LIZnrzOuk4WyjqEiLG8" : {
"disliked" : true,
"id" : 4805,
"name" : "Ccc"
}
}
}
}
}
What I need to achieve is getting a list of all liked item-names, and ideally counting how often an item is liked.
Is there a simple tool or script to do that? Ruby or Javascript would be preferred. Thanks a lot!

You can parse your JSON data in ruby like below
result_hash = JSON.parse(result)
result_ary = result_hash["users"].collect do |k,v|
v["items"].values.select{|v1| v1["liked"] == true }
end
result_data = result_ary.flatten
result of parsing
=> [{"liked"=>true, "id"=>3674, "name"=>"Bbb"}, {"id"=>396, "liked"=>true, "name"=>"Aaa"}]
Now its very easy for getting your required result
result_data.collect{|x| x["name"] }
=> ["Bbb", "Aaa"]
result_data.count {|x| x["name"] == "Aaa"}
=> 1
result_data.count {|x| x["name"] == "Bbb"}
=> 1

Re-structure the data of the MongoDB $lookup Query.

I want this to be the result
help me, thank you
{
"_id" : ObjectId("5b74f57d3eb9591fcc069406"),
"received_by" : ObjectId("5b6bac617e9f754ff8aebd65"),
"received_date" : "2019",
"code" : "TRSV16081800007",
"items" : [
{
"m_souvenir_id" : ObjectId("5b70e98ccb72df3bec00c94a"),
"qty" : "10"
},
{
"m_souvenir_id" : ObjectId("5b70e98ccb72df3bec00c94a"),
"qty" : "10"
},
]
}
the result is like this
{
"_id" : ObjectId("5b74f57d3eb9591fcc069406"),
"received_by" : ObjectId("5b6bac617e9f754ff8aebd65"),
"received_date" : "2019",
"code" : "TRSV16081800007",
"items" : [
{
"m_souvenir_id" : ObjectId("5b70e98ccb72df3bec00c94a"),
"qty" : "10"
}
]
}
/* 2 */
{
"_id" : ObjectId("5b74f57d3eb9591fcc069406"),
"received_by" : ObjectId("5b6bac617e9f754ff8aebd65"),
"received_date" : "2019",
"code" : "TRSV16081800007",
"items" : [
{
"m_souvenir_id" : ObjectId("5b70e9d7cb72df3bec00c94b"),
"qty" : "20"
}
]
}
I have a project with nosql in mongodb
I have a problem with nosql in mongodb, I've tried searching in various sources, but the results are still not what I wantI have a project like this in mongodb,
db.t_souvenir.aggregate([
{ $lookup: { from: "t_souvenir_item", localField:"_id", foreignField:"t_souvenir_id", as: "Items"}},
{ $unwind : "$Items" },
{ $project : {
"code":1,
"received_by":1,
"received_date":1,
items : {
"m_souvenir_id":"$Items.m_souvenir_id",
"qty":"$Items.qty",
},
}};**strong text**
]);

MongoDB .find() only ObjectId's embedded in an Array.

I am trying to get only the ObjectId's from One specific Document that is embedded in the projects Array.
Basically I am trying to make a database that will have users and each user will have there own projects.
Thank you !
db.users.find().pretty()
{
"_id" : ObjectId("5762c0cf2b9a78006373a684"),
"name" : "seq",
"pass" : "seq",
"projects" : [
{
"pid" : ObjectId("5762c0ba2b9a78006373a682"),
"name" : "aaa"
},
{
"pid" : ObjectId("5762c0ba2b9a78006373a683"),
"name" : "bbb"
}
]
}
{
"_id" : ObjectId("5762c28d2b9a78006373a687"),
"name" : "leq",
"pass" : "leq",
"projects" : [
{
"pid" : ObjectId("5762c2892b9a78006373a685"),
"name" : "ccc"
},
{
"pid" : ObjectId("5762c2892b9a78006373a686"),
"name" : "ddd"
}
]
}

let say we want two pids
{"pid" : ObjectId("5762c0ba2b9a78006373a682")} and
{"pid" : ObjectId("5762c2892b9a78006373a686"),}
and only inner documents
so required response should look like:
{
"_id" : ObjectId("5762c0ba2b9a78006373a682"),
"name" : "aaa"
},{
"_id" : ObjectId("5762c2892b9a78006373a686"),
"name" : "ddd"
}
Aggregation framework can manipulate documents, match only needed ones and transform inner structure by project phase:
var match = {
$match : {
"projects.pid" : {
$in : [ObjectId("5762c0ba2b9a78006373a682"),
ObjectId("5762c2892b9a78006373a686")]
}
}
}
var unwind = {
$unwind : "$projects"
};
// now move array objet as top level object
var project = {
$project : {
_id : "$projects.pid",
name : "$projects.name",
// list other fields here
}
}
db.vic.aggregate([match, unwind, match, project])

Meteor find is returning null with variable [duplicate]

This question already has an answer here:
Updating template with session variable and subscription/publication only updates with previous query and appends information
(1 answer)
Closed 7 years ago.
Description of the problem:
I have two collections videos and specs. videos collection has a key called spec which corresponds to a specs id. Both collections are not empty.
My Template Helper:
Template.List.helpers({
videos: function(){
var vids = Videos.find({ online: false}).fetch();
return vids.map(function(value){
console.log("id: " + value.spec);
console.log(Specs.find({ id: value.spec }).fetch());
//Issue here
value.specName = Specs.find({ id: value.spec }).fetch()[0].name;
return value;
});
}
});
As you can see in my template helper I loop through the video array and add specName to the array.
The main problem comes from this specific line:
value.specName = Specs.find({ id: value.spec }).fetch()[0].name;
and more specifically this line: Specs.find({ id: value.spec }).fetch()
which will return null every time.
What I've tried:
Naturally, my first thought would be to check what value.spec returns. And it returns an int between 1 and 15 (included) which is right. If value.spec is right, then how come the find() doesn't return anything?
I then decided to hard set it and tried this:
Specs.find({ id: 2}).fetch()
And this worked. Which is weird because on multiple occasions value.spec returns 2...
I've also tried intParse(value.spec) just in case, however that didn't work either.
Question
Why does Specs.find({ id: value.spec }).fetch() return null knowing that value.spec is set correctly and that a hard coded number works?
Requested json data: (from meteor mongo)
specs:
{ "_id" : "XKXHtQuiFsAew3dDy", "id" : 1, "name" : "Endocrine surgery" }
{ "_id" : "68jFidAMXTXpQtQye", "id" : 2, "name" : "General and digestive" }
{ "_id" : "GZSXToRXMfJgnH3CY", "id" : 3, "name" : "Pediatric surgery" }
{ "_id" : "T2mBz2gsXEqQaybmq", "id" : 4, "name" : "Thoracic surgery" }
{ "_id" : "hnuQzZiPKvYYDZhc8", "id" : 5, "name" : "Equipment" }
{ "_id" : "byE3A6HchvfhKdmR8", "id" : 6, "name" : "Gynecology" }
{ "_id" : "u5rrPB7asGW3NC6B2", "id" : 7, "name" : "Urology" }
{ "_id" : "umxKvR66oEx5dRppf", "id" : 8, "name" : "Cardiovascular surgery" }
{ "_id" : "bPcBTZn3t5ubRRcrQ", "id" : 9, "name" : "Endoscopic surgery" }
{ "_id" : "yNyAqQPoreNtdRZ34", "id" : 10, "name" : "NOTES" }
{ "_id" : "KG794eakRaztEqehG", "id" : 11, "name" : "Robotic surgery" }
{ "_id" : "QBrtvTg4GT7Tf7cAJ", "id" : 12, "name" : "Skull base surgery" }
{ "_id" : "HEhq6oBjuuMnrxE5a", "id" : 13, "name" : "Arthroscopy and upper limb surgery" }
{ "_id" : "xwpgHqZpBQP7WAnd5", "id" : 14, "name" : "Single port surgery" }
{ "_id" : "K4BgFupwNdDGD3449", "id" : 15, "name" : "Telemicrosurgery" }
videos:
{ "_id" : "L5Qi7YRRhn6Sfcjk8", "id" : "vd01en1065e", "title" : "Right inguinal hernia: open plug technique", "authors" : [ "E Pelissier" ], "date_published" : "2004-09-27", "abstract" : "", "tags" : [ "" ], "spec" : 2, "private" : true, "online" : false }
{ "_id" : "M8cuLW6KNCqKeP9vF", "id" : "vd01en1074e", "title" : "Laparoscopic splenectomy, posterior approach", "authors" : [ "D Mutter", " F Rubino" ], "date_published" : "2004-09-27", "abstract" : "", "tags" : [ "" ], "spec" : 2, "private" : true, "online" : false }
{ "_id" : "Ptzrxw8GifeMvQk9k", "id" : "vd01en1090e", "title" : "Intussusception of the intestine in the newborn", "authors" : [ "F Becmeur", " D Christmann", " I Kauffmann" ], "date_published" : "2004-09-27", "abstract" : "", "tags" : [ "" ], "spec" : 3, "private" : true, "online" : false }
{ "_id" : "oHWcX3vCBHuZQM9hR", "id" : "vd01en1103e_2", "title" : "Appendicular peritonitis: laparoscopic conversion", "authors" : [ "B Navez" ], "date_published" : "2001-11-05", "abstract" : "", "tags" : [ "" ], "spec" : 2, "private" : true, "online" : false }
{ "_id" : "6uzmxYxhd5DDuS2gG", "id" : "vd01en1108e", "title" : "Diaphragmatic hernias", "authors" : [ "F Becmeur" ], "date_published" : "2001-11-28", "abstract" : "", "tags" : [ "" ], "spec" : 3, "private" : true, "online" : false }
{ "_id" : "yHqruiQYeeQ9SDHpH", "id" : "vd01en1112e", "title" : "Laparoscopic excision of the cystic stump", "authors" : [ "J Leroy" ], "date_published" : "2004-09-27", "abstract" : "", "tags" : [ "" ], "spec" : 2, "private" : true, "online" : false}
{ "_id" : "fmjtk5WAEKitMxyGj", "id" : "vd01en1114e", "title" : "Laparoscopic gastric banding in a patient with a BMI of 40", "authors" : [ "JM Zimmermann", " D Fölscher" ], "date_published" : "2004-09-27", "abstract" : "", "tags" : [ "" ], "spec" : 2, "private" : true, "online" : false}
I've been stuck on this problem for a couple hours, I didn't want to post this on SO since I do believe it's a simple problem. However, it is mind boggling.

The problem here is the publication/subscription issue. You did not mention it, how do you handle publications and subscriptions but that is most likely the issue. What is happening is that when you browse your videos collection, which subscription is ready (since you hae any data in it) here: Videos.find({ online: false}) that not necessarly means that (in that precise moment) subscription handling Spec collection is ready as well. So even if on the server the query is working, on the client it's null, because the data are not synced between client and server YET. so you have to wait until both subscriptions are ready somehow. You can use template subscriptions, or waitOn function in your router.

First of all check on server side that your publication and subscription is ready and returning you back data check this like as
Meteor.publish('Videso', function () {
var result= Videso.find({});
console.log(result);
return result
});
if console.log returning you records on server side i have a solution then your
problem
the solution of your problem is that
Template.List.helpers({
videos: function(){
var vids = Videos.find({ online: false}).map(function (value) {
console.log("id: " + value.spec);
var idValue = Specs.findOne({ "id": value.spec })
console.log("idValue===",idValue)
return _.extend(value, idValue);
});
console.log(vids); //here merged data of both table having
// relvent record will returned
return vids;
}
});
Just implement it and check data on your template it will be ready for you and vote me then :)