I have the following 2 schemas:
bookSchema = new mongoose.Schema(
{
name: {
type: String,
required: [true, 'Name required']
},
author:{
type:mongoose.Schema.ObjectId,
ref: 'Author'
}
authorSchema = new mongoose.Schema(
{
name: {
type: String,
trim: true,
})
I have an array of Author object references and I need to filter books based on these:
authors: [
{
_id: new ObjectId("6358edf901dbe13bc738b63b"),
name: 'Name 2',
__v: 0
},
{
_id: new ObjectId("63592660ca309b7c1a94fb04"),
name: 'Name 1',
__v: 0
}
]
I have tried with below code but it gives empty array as result:
Book.aggregate([ { $match: { $expr: { $in: ['Author', authors] } } } ,])
Related
I am a bit puzzled by populate in MongoDB.
I've got a Schema:
import { Schema, Document, model } from "mongoose";
export interface ProductGroupType {
id: Schema.Types.ObjectId,
title: String,
name: String,
description: String,
}
const ProductGroupSchema: Schema<Document<ProductGroupType>> = new Schema({
title: { type: String, trim: true },
name: { type: String, trim: true },
description: { type: String, trim: true },
}, { collection: "productGroups", timestamps: true });
export const ProductGroupModel = model('ProductGroup', ProductGroupSchema);
and products
import { Schema, Document, model } from "mongoose";
import { plugin as autocomplete } from 'mongoose-auto-increment';
const ProductSchema: Schema<Document<IProduct>> = new Schema({
article: Number,
name: String,
category: { type: Schema.Types.ObjectId, ref: 'ProductCategory' },
group: { type: Schema.Types.ObjectId, ref: 'ProductGroup' },
price: { type: Number, default: 0 },
discount: { type: Number, default: 0 },
stock: {
available: { type: Number, default: 0 },
reserved: { type: Number, default: 0 },
},
images: [Object],
description: String,
productDetails: Object,
}, { collection: "products", timestamps: true });
ProductSchema.plugin(autocomplete, {
model: 'Product',
field: 'article',
startAt: 10000,
});
export const ProductModel = model('Product', ProductSchema);
I need to make a request and group on the MongoDB side data by the field 'group'.
I can make this like this:
await ProductModel.aggregate([
{ $match: { category: Types.ObjectId(queryCategory.id) } },
{
$group: {
_id: '$group',
products: {
$push: {
id: '$_id',
name: '$name',
article: '$article',
price: '$price',
discount: '$discount',
description: '$description',
group: '$groupName',
}
},
count: { $sum: 1 },
}
},
]);
but the output here is:
[
{ _id: 61969583ad32e113f87d0e99, products: [ [Object] ], count: 1 },
{
_id: 61993fff452631090bfff750,
products: [ [Object], [Object] ],
count: 2
}
]
almost what I need but I've been playing around with population and I cannot make it work with Aggregation framework.
I already tried to use the 'lookup' operator but it returns an empty array and doesn't want to work.
That's how I wanted to make it work:
const products: Array<IProduct> = await ProductModel.aggregate([
{ $match: { category: Types.ObjectId(queryCategory.id) } },
{
$group: {
_id: '$group',
products: {
$push: {
id: '$_id',
name: '$name',
article: '$article',
price: '$price',
discount: '$discount',
description: '$description',
group: '$groupName',
}
},
count: { $sum: 1 },
}
},
{
$lookup: {
"from": "productGroups",
"localField": "group",
"foreignField": "_id",
"as": "groupName"
},
},
]);
Is it possible to get the same result as I've got now but populate in the same query group field?
So far the only way I've managed to populate it like this as the second request:
await ProductGroupModel.populate( products.map( (product: any) => {
return {
_id: new ProductGroupModel(product),
products: product.products,
count: product.count,
}
} ), { "path": "_id" } )
In a MongoDB aggregation pipeline, the $group stage passes along only those field explicitly declared in the stage.
In the same pipeline you show, the documents passed along by the $group stage would contain the fields:
_id
products
count
When the exector arrives a the $lookup stage, none of the documents contain a field named group.
However, the value previously contained in the group field still exists, in the _id field.
In the $lookup stage, use
"localField": "_id",
to find documents based on that value.
I am very new to mongoDB and mongoose and I also know questions like this has been already asked but still I didn't get any luck.
So what I am trying to do is I have 2 collections one is products and second is categories and I am trying to get the products that are of category type: fruits
product.model.js
const mongoose = require('mongoose')
const productSchema = new mongoose.Schema({
category: {
type: mongoose.Schema.Types.ObjectId,
ref: 'Category'
},
name: {
type: String,
required: true,
unique: true
},
price: {
type: Number,
required: true
},
image: {
type: String,
required: true
},
description: {
type: String,
required: true
}
})
const Product = mongoose.model('Product', productSchema)
module.exports = Product
category.model.js
const mongoose = require('mongoose')
const categorySchema = new mongoose.Schema({
name: {
type: String,
required: true,
unique: true,
lowercase: true
}
})
const Category = mongoose.model('Category', categorySchema)
module.exports = Category
products collecction
[ { _id: 5ffc9795355f3707ec326f51,
name: 'apple',
price: 80,
image: 'apple1.jpg',
description:
'Do you really need description for this ??',
category: 5ffc94e8a7542a37101a119c,
__v: 0 },
{ _id: 5ffd54409793c33b183376b8,
name: 'Beef',
price: 180,
image: 'beef1.jpg',
description: 'Don\'t you dare to ask about beef in india',
category: 5ffc94dda7542a37101a119b,
__v: 0 },
{ _id: 5ffd54969793c33b183376b9,
name: 'Mango',
price: 100,
image: 'mango1.jpg',
description:
'Have some manog because you cannot eat the bottle of slice like katrina kaif do, its crazy',
category: 5ffc94e8a7542a37101a119c,
__v: 0 } ]
categories collection
[ { _id: 5ffc947ea7542a37101a119a, name: 'vegitables', __v: 0 },
{ _id: 5ffc94dda7542a37101a119b, name: 'non-veg', __v: 0 },
{ _id: 5ffc94e8a7542a37101a119c, name: 'fruits', __v: 0 } ]
Now I want to the get the products whose category are fruits
I know I have to use aggregation and lookup for this I also tried but didn't get any luck, this is my code
const Product = require('./models/product')
const Category = require('./models/category')
const test = async () => {
try {
var query = [
{
$lookup: {
from: "product",
localField: "category",
foreignField: "_id",
as: "product"
}
}]
const productCate = await Product.aggregate(query)
console.log(productCate)
// const productCat = await Product.find().populate({
// path: 'category',
// match: {name: 'fruits'}
// }).exec()
// console.log(productCat)
}catch(e) {
}
}
test()
UPDATE-1
I also tried ppuplate but still didn't get the response as expected, this is my code:
const test = async () => {
try {
const productCat = await Product.find().populate({
path: 'category',
match: {name: 'fruits'}
}).exec()
console.log(productCat)
}catch(e) {
}
}
test()
this is my output
[ { _id: 5ffc9795355f3707ec326f51,
name: 'apple',
price: 80,
image: 'apple1.jpg',
description:
'Do you really need description for this, how dumb are you ??',
category: { _id: 5ffc94e8a7542a37101a119c, name: 'fruits', __v: 0 },
__v: 0 },
{ _id: 5ffd54409793c33b183376b8,
name: 'Beef',
price: 180,
image: 'beef1.jpg',
description: 'Don\'t you dare to ask about beef in india',
category: null,
__v: 0 },
{ _id: 5ffd54969793c33b183376b9,
name: 'Mango',
price: 100,
image: 'mango1.jpg',
description:
'Have some manog because you cannot eat the bottle of slice like katrina kaif do, its crazy',
category: { _id: 5ffc94e8a7542a37101a119c, name: 'fruits', __v: 0 },
__v: 0 } ]
Here I also get the beef that is fall under non-veg category but with the category null. Actually I only want the fruits category products.
you can following this code
const test = async () => {
try {
let categoryId = await Category.findOne({name:"fruits"}).select("_id")
const productCat = await Product.find({category:categoryId}).populate(
"category"
).lean()
console.log(productCat)
}catch(e) {
}
}
test()
you can do with with populate match without using aggregation:
Product.find().populate({
path: 'category',
match: { 'name': 'fruits' }
})
.exec()
I am building an e-commerce application and this is my orders schema.
const mongoose = require("mongoose");
const orderSchema = new mongoose.Schema({
buyer: {
type: mongoose.Schema.Types.ObjectId,
ref: "buyer",
required: true
},
items: [{
item: {
type: mongoose.Schema.Types.ObjectId,
ref: "item",
},
quantity: {
type: Number,
default: 1
}}
],
seller: {
type: mongoose.Schema.Types.ObjectId,
ref: "seller",
required: true
},
location: {
type: {
type: "String",
enum:['Point']
},
coordinates: {
type: [Number],
index: '2dsphere'
}
},
sendAt:{
type: Date,
default: Date.now
}
});
const orderModel = mongoose.model("orders", orderSchema);
module.exports = orderModel;
I want to have an array having item-reference-id and quantity.
But with the above schema when i enter data, each item is acting as an another sub-document and having _id. Query response image.
I have found solution:
order: [
{
_id: false,
item: {
type: mongoose.Schema.Types.ObjectId,
ref: "items",
required: true,
},
quantity: { type: Number },
},
],
_id: false will stop the subdocument from creating another id for the subdocument.
How to use populate api to get inbox data populated by user model?
Here shcemas:
const inboxSchema = Schema({
messageList: [{
from: { type: Schema.Types.ObjectId, require: true, ref: 'user' },
to: { type: Schema.Types.ObjectId, require: true, ref: 'user' },
}]
})
const userSchema = Schema({
name: { type: String, require: true },
})
expected result, eg:
{
"messageList": [
{
from: {
_id: xxxxxxxxxxxxxxx,
name: 'Smith'
},
to: {
_id: zzzzzzzzzzzzzzz,
name: 'John'
}
}
]
}
You could also use The .populate() Query like Below."
.populate([{
path:"messageList.from"
select:"_id name"
},{
path:"messageList.to"
select:"_id name"
}])
I have the following documents
User Schema:
var UserSchema = new Schema({
name: String,
email: { type: String, lowercase: true },
offers: [],
anyCountry: {type: Boolean, default: false},
city: String,
});
Tags Schema
var TagSchema = new Schema({
text: String,
dateCreated: { type: Date, default: Date.now}
});
I am aggregating it this way:
User.aggregate(
{$match: {
$or: [
{'isBlocked': false},
{'isBlocked': {$exists: false}}
]}},
{ $project: {"offers": 1, _id: 0, city: 1, name: 1}},
{ $unwind: "$offers" },
{
$match: {
$and: [
{'offers': { $not: { $size: 0} }},
{'offers.type': type}
]
}
},
{ $sort: {"offers.dateCreated": -1} },
function (err, result) {
if (!err) {
return res.json({status: 'success', data: result});
} else {
return res.send(err);
}
}
)
The output is ok, but it contains tags as array. What I need is:
to have array values assigned to a computed field "offers.tagsList" as a coma separated sting {offers.tagsList = 'tag1, tag2, tag3, ...'}.
check if filed offers.anyCountry doesn't exists and add it to the output with value false.
Thanks!