mongoose: update field, push object in array [duplicate] - node.js

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Stop Mongoose from creating _id property for sub-document array items
(7 answers)
Closed 7 years ago.
I would like to add an element in an array in a mongo database:
db.keypairs.update( {pubkey: "1234567890"}, { $push: {listTxId: {txHash: "yyy", spent: false} } } )
The result is perfect:
listTxId" : [ { "txHash" : "xxx", "spent" : true },{ "txHash" : "yyy", "spent" : false } ]
Now I would like to do the same with node.js and mongoose
var res = wait.forMethod(Keypair,'update', {pubkey: "1234567890"}, { $push: { "listTxId": {"txHash":"zzz", "spent":false} } } );
Keypair is my node.js model for the mongoose collection:
var Keypair = require('./app/models/Keypair');
and wait.forMethod comes from a node module:
var wait = require('wait.for');
In the result, I have this "_id" element :
{ "txHash" : "zzz", "spent" : false, "_id" : ObjectId("56561571fea5d9a10a5771fd") }
QUESTION: where this ObjectId come from ? How can I get rid of it ?
UPDATE: mongoose schema:
var keypairSchema = mongoose.Schema({
userId : { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
pubkey : String,
privkeyWIF : String, // temp
balance : Number,
listTxId : [{
txHash : String,
spent : Boolean
}],
walletId : { type: mongoose.Schema.Types.ObjectId, ref: 'Wallet' },
description : { type: String, maxlength: 40 },
comments : String,
isMasterKey : { type: Boolean, default: false },
date : Date
});

Answer 1

Mongoose will put ids in your subdocument arrays. listTxId is a subdocument array. You can add _id: false to your schema to prevent this:
var keypairSchema = mongoose.Schema({
userId : { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
pubkey : String,
privkeyWIF : String, // temp
balance : Number,
listTxId : [{
_id: false,
txHash : String,
spent : Boolean
}],
walletId : { type: mongoose.Schema.Types.ObjectId, ref: 'Wallet' },
description : { type: String, maxlength: 40 },
comments : String,
isMasterKey : { type: Boolean, default: false },
date : Date
});