Check mongoose connection state without creating new connection

Since the mongoose module exports a singleton object, you don’t have to connect in your test.js to check the state of the connection:

// test.js
require('./app.js'); // which executes 'mongoose.connect()'

var mongoose = require('mongoose');
console.log(mongoose.connection.readyState);

ready states being:

• 0: disconnected
• 1: connected
• 2: connecting
• 3: disconnecting