How to autoIncrement id's and post to mongodb using node js - node.js

Question

I want to increment id's automatically in the mongoDB while posting the data. I am able to attach date for the req.body. How to attach ids with auto incrementation?
This is my post call:
router.post('/addVisualization', function (req, res, next) {
MongoClient.connect(url, function (err, db) {
if (err) throw err;
var dbo = db.db(dbName);
req.body.dateOfEntry = new Date();
function getNextSequence(id) {
var ret = db.counters.findAndModify(
{
query: { _id: id },
update: { $inc: { seq: 1 } },
new: true
}
);
return ret.seq;
}
dbo.collection("visualization").insertOne(req.body, function (err, resDB) {
if (err) {
throw err;
res.status(401);
res.send({
"status": 401,
"message": "Some error happened"
});
}
else {
console.log("1 document inserted");
res.status(201)
res.send({
"body": req.body,
"status": 201,
"message": "visualization has been added"
});
}
});
db.close();
});
});

Answer 1

Try out the below code to auto increment id's in mongoDB.
router.post('/addVisualization', function (req, res, next) {
MongoClient.connect(url, {
useNewUrlParser: true
}, function (err, db) {
if (err) throw err;
var dbo = db.db(dbName);
req.body.dateOfEntry = new Date();
req.body.isDeleted = "false";
var countRow;
var sequenceDocument = dbo.collection("counterVisualization").findOneAndUpdate({
_id: "tid"
}, {
$inc: {
sequence_value: 1
}
}, {
new: true
});
dbo.collection("counterVisualization").find({
_id: "tid"
}).toArray(function (err, result1) {
if (err) {
throw err;
} else {
countRow = result1[0].sequence_value;
req.body["_id"] = countRow;
dbo.collection("visualization").insertOne(req.body, function (err, resDB) {
if (err) {
throw err;
res.status(401);
res.send({
"status": 401,
"message": "Some error happened"
});
} else {
console.log("1 document inserted");
res.status(201)
res.send({
"body": req.body,
"status": 201,
"message": "visualization has been added"
});
}
});
}
});
});
});

Answer 2

In mongo db you don't have a auto increment ids as mysql or oracle, Please take a look at this tutorial for how to do it out of the box.

Answer 3

Use a separate counters collection to track the last id of the sequence.
db.counters.insert(
{
_id: "userid",
seq: 0
}
)
db.counters.insert(
{
_id: "productid",
seq: 0
}
)
Create a getNextSequence function that accepts a name of the sequence.
function getNextSequence(name) {
var ret = db.counters.findAndModify(
{
query: { _id: name },
update: { $inc: { seq: 1 } },
new: true,
upsert : true // Creates a new document if no documents match the query
}
);
return ret.seq;
}
Use this getNextSequence() function during insert.
db.users.insert(
{
_id: getNextSequence("userid"),
name: "Mr. X",
// ... more fields
}
)
db.products.insert(
{
_id: getNextSequence("productid"),
name: "Mr. Y",
// ... more fields
}
)