How to save nested array in MongoDB using Mongoose and NodeJS - node.js

Question

Can anyone explain me how to save the nested array items into mongodb with mongoose and nodejs?.
Here is a schema I am using.
var demoSchema = ({
"r_id": Number,
"r_label": String,
"entity": [{
"d_label": String,
"d_type": String
}
]
})
And here is Nodejs function I am using to save the data into db
app.route("/mypages/rooms")
.post(function(req, res) {
var db = mongoOp.demo();
var response = {};
req.checkBody("r_id", "Enter a valid r_id address.").notEmpty();
req.checkBody("r_label", "Enter a valid label address.").notEmpty();
var errors = req.validationErrors();
if (errors) {
console.log(errors);
console.log(req.body);
res.status(500);
res.end('500 Server Error');
//res.render('addrooms',{flag:1});
return;
} else {
db.r_id = req.body.r_id;
db.r_label = req.body.r_label;
db.entity = req.body.entity;
db.save(function(err) {
if (err) {
findfromdb(req, res, 2); //own function for implementation purpose
} else {
findfromdb(req, res, 1);
}
});
//var middleVar = req.body.resources;
// console.log(middleVar[0].d_rgb);
}
});

Answer 1

set entity with array []
db.entity = [{}];
app.route("/mypages/rooms")
.post(function(req, res) {
var db = mongoOp.demo();
var response = {};
req.checkBody("r_id", "Enter a valid r_id address.").notEmpty();
req.checkBody("r_label", "Enter a valid label address.").notEmpty();
var errors = req.validationErrors();
if (errors) {
console.log(errors);
console.log(req.body);
res.status(500);
res.end('500 Server Error');
//res.render('addrooms',{flag:1});
return;
} else {
db.r_id = req.body.r_id;
db.r_label = req.body.r_label;
db.entity = [{
"d_label": req.body.label_type,
"d_type": req.body.d_type
}];
db.save(function(err) {
if (err) {
findfromdb(req, res, 2); //own function for implementation purpose
} else {
findfromdb(req, res, 1);
}
});
//var middleVar = req.body.resources;
// console.log(middleVar[0].d_rgb);
}
});
The below operation adds the element label_type and d_type to entity array if they does not exist in the array, if they exists, then they won't be added
https://docs.mongodb.com/manual/reference/operator/update/addToSet/
Model.update(
query, // { _id: 1 }
{
$addToSet: {
"enity": {
"d_label": req.body.label_type,
"d_type": req.body.d_type
}
}
}
)
have a look at this answer
Pushing item to Mongodb collection array