how to connect local mongodb with mongoose code example

Example 1: connecting to mongoDB using mongoose

//Import the mongoose module
var mongoose = require('mongoose');

//Set up default mongoose connection
var mongoDB = 'mongodb://127.0.0.1/my_database';
mongoose.connect(mongoDB, {useNewUrlParser: true, useUnifiedTopology: true});

//Get the default connection
var db = mongoose.connection;

//Bind connection to error event (to get notification of connection errors)
db.on('error', console.error.bind(console, 'MongoDB connection error:'));

Example 2: node js connect to mongodb using mongoose

//connect with mongodb
mongoose.connect('mongodb://localhost:27017/your_db_name', {useNewUrlParser: true});
//you can also specify with user and pass
mongoose.connect('mongodb://username:password@host:port/database?options...', {useNewUrlParser: true});
//or goto docs https://mongoosejs.com/docs/connections.html

Example 3: TypeError: mongoose__WEBPACK_IMPORTED_MODULE_2___default.a.connect is not a function at _callee$ (db.js:11) at tryCatch (runtime.js:45)

try {
  mongoose.connect(MONGODB_URI || 'mongodb://localhost/YOUR_DB_NAME', {
      useNewUrlParser: true,
      useUnifiedTopology: true
    }, () =>
    console.log("connected"));
} catch (error) {
  console.log("could not connect");
}