mongodb what is mongoose code example

Example 1: mongoose

import express from 'express';
or
const exporess = require('express');
import mongoose from 'mongoose';
or
const mongoose = require('mongoose');
const app = express();
mongoose.connect('mongodb://localhost:27017/mongo-tree' , {
    useNewUrlParser: true,
    useUnifiedTopology: true
});

const db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function() {
console.log('connected db')
});
app.use('/', (req, res) => {
    res.send('hello');
}
);
const port = process.env.PORT || 5000
app.listen(port, () => {
console.log('running');
})
//for es6 >npm i @babel/core @babel/node @babel/preset-env --save-dev

//create  .babelrc file and put this 
{
    "presets": [
        "@babel/preset-env"
    ]
}
//and package.json
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "nodemon --exec babel-node server"
  },

Example 2: mongoose

Extra clever
Earthbound spirit
Ghost in the form
Of a mongoose

And I have hands
And I have feet
I'll never die
I am a freak

Hello, I'm here
I'm living in the wall
I know I might be small, but
I, I, I, am a
Freak

Thou wilt never
Know what I am
I am the fifth dimension
And I'll split the atom

And if you see me
You're paralyzed
Pillar of salt
You're mummified

Hello, I'm here
I'm living in the wall
I know, I might be small
But I am the Eighth Wonder

And I was born
1852
And I was born
In India

And I shall haunt
Like the Buggane
With such weird noise
And clanking chains

Hello, I'm here
I'm living in the wall
I know I might be small, but
I, I, I, am a
Freak

I say "vanished"
To underground
Jim, let me go
I watch like Hell

And I have hands
And I have feet
I'll never die
I am a freak

Hello, I'm here
I'm living in the wall
I know I might be small
But I am the eighth wonder

Eighth wonder of the world
You'll never get to see
What in the name of God can I be?