How to find text from populated model in mongoose? - node.js

Question

We have two models:
User
const userSchema = new mongoose.Schema({
name: {
type: String
},
email: {
type: String
},
vehicleId: {
type: mongoose.Schema.Types.ObjectId,
ref: 'vehicle'
}
})
Vehicle
const vehicleSchema = new mongoose.Schema({
name: {
type: String
},
color: {
type: String
}
})
Now, we have to find user input from user's ( name, email ) & also from vehicle's ( name, color )
- If user search "pink" then we have to find that if any user has with name, email or them vehicle include "pink" keyword or not.
- If string match from reference model then we have to return whole record.
Can you please help us, how to achieve this?

Answer 1

You can first run a query on a Vehicle model to fetch all vehicles that have name pink
let vehicleIds=await Model.Vehicle.aggregate([
{$match:{$or:[
{name:{$regex:"pink",$options:"i"}},
{color:{$regex:"pink",$options:"i"}
]}},
{$group:{_id:null,ids:{$push:"$_id"}}}
])
here if vehicleIds is not empty, then vehicles[0].ids will have vehcileIds that have pink in name or color
let vehcileIds=[]
if(vehicles.length) vehcileIds=vehicles[0].ids
after above query runs run another query in the user model
let users= await Models.User.find({$or:[
{name:{$regex:"pink",$options:"i"}},
{email:{$regex:"pink",$options:"i"}
{vehicleId:{$in:}}
]})

Answer 2

I think, the best thing you can do is, Text Search.
ANSWER 1:
1.1. Step one
You have to create text index on your collection to perform text search.
create text index with
db.user.createIndex({"name":"text", "email": "text"})
db.vehicle.createIndex({"name": "text", "color": "text"})
we have to create text index on both collection as we want to perform text search on both collections.
*
Note:
as we are creating a text index on "name", "email" from User & "name", "color" from Vehicle, you can only perform text search on this four fields in respective collections.
you can assign weights to fields so that you can sort your result according to text score. (you must do this while creating index).
*
1.2. Step two
(i am assuming you are using Javascript and mongoose here.)
db.collection("users").aggregate({$match:{$text: {$search: "pink"}}},
(err, userData: any)=>{
if(err){
return err;
}
if(userdata.length){
let vehicleIds = userData.map((user) => mongoose.Types.ObjectId(user.vehicleId));
db.collection("vehicles").aggregate({$match:{$text:{$search:"pink", _id: {$in: vehicleIds}}}}, (err, vehicleData)=>{
//this will be your vehicle details
})
})
}else{
console.log("no Data found");
}
*
The problem with this approach is you have to fire two queries because of the restrictions in Text Search and extra overhead of text index on collections.
Good Thing is you get a lot of ways to perform a search, you can sort results according to relevance with text score, it is fast than the regular expression and you get better results, you get stemming, you get stop words (please ref links that are given).
*
ANSWER 2:
you can use regular expression
db.collection("users").aggregate({$match:{$or:[{name:{$regex: /pink/}}, {email:{$regex: /pink/}}]}},
{$lookup:{from:"vehicles", localField:"vehicleId", foreignFild:"_id", as:"vehicleDetail"}},
{$unwind:{path:"$vehicleDetail"}},
{$match:{$or:[{name:{$regex:/pink/}},{color:{$regex:/pink/}}]}}
(err, data)=>{
})
ANSWER 3:
If you dont want to prefer above options, you can fire normal query too
db.collection("users").aggregate({$match:{$or:[{name:{$regex: /pink/}}, {email:{$regex: /pink/}}]}},
{$lookup:{from:"vehicles", localField:"vehicleId", foreignFild:"_id", as:"vehicleDetail"}},
{$unwind:{path:"$vehicleDetail"}},
{$match:{$or:[{name:{$regex:/pink/}},{color:{$regex:/pink/}}]}}
(err, data)=>{
})
Hope this helps. :-)
Correct me if I am wrong anywhere. :-)

Answer 3

Below steps you should follow:
Find user by name and email.
Populate vehicle
Again match with the color.
db.getCollection('User').aggregate([
{ $match: { email: "h#gmail.com", name: "Hardik"}},
{ $lookup: {from: 'Vehicle', localField: 'vehicleId', foreignField: '_id', as: 'vehicle'} },
{ $match: { "vehicle.color": {$regex: '.*'+ "Pink" +'.*', $options: 'si'}}},
])
Data:
User
{
"_id" : ObjectId("5d51bd5ef5fc3d6486b40ffb"),
"email" : "h#gmail.com",
"name" : "Hardik",
"vehicleId" : ObjectId("5d539786f5fc3d6486b4252b")
}
Vehicle
{
"_id" : ObjectId("5d539786f5fc3d6486b4252b"),
"name" : "Bike",
"color" : "Pink"
}
Output:
{
"_id" : ObjectId("5d51bd5ef5fc3d6486b40ffb"),
"email" : "h#gmail.com",
"name" : "Hardik",
"vehicleId" : ObjectId("5d539786f5fc3d6486b4252b"),
"vehicle" : [
{
"_id" : ObjectId("5d539786f5fc3d6486b4252b"),
"name" : "Bike",
"color" : "Pink"
}
]
}
Hope this helps!