quest6.md

Getting MEAN

An Introduction to API-Centered Application Development with Node.js and MongoDB

Quest 6: Enter MongoDB - Native JavaScript

Leafie wants to keep all of the information in a MongoDB database. First off we need to setup a connection to our MongoDB database. The basic steps to connect with the database are:

• Use MongoClient to establish a connection
• Pass in the url to connect to. In our case it will be localhost with the default port of 27017.
• Select the database to which to connect to.

Let's add MongoDB to our Node.js project:

npm install --save mongodb

In the api/data folder, let's create a new file called db.js.

let MongoClient = require('mongodb').MongoClient;


const dbName = 'mdbw18';
const mdbPort = 27017;
const url = 'mongodb://localhost:' + mdbPort + '/' + dbName;

class Connection {
    constructor(uri, name) {
        this.db = null;
        this.uri = uri;
        this.name = name;
    }

    connect() {
        if(this.db) {
            return Promise.resolve(this.db);
        } else {
            return MongoClient.connect(this.uri)
                .then(client => {
                    this.db = client.db(this.name);
                    return this.db;
                });
        }
    }
}

module.exports = new Connection(url, dbName);

With a successful connection in place, next up is to put data in so we can get data out of the database. Hmmm, this sounds like a CRUDdy job. We'll need to do these CRUD operations inside a MongoDB connection...

Let's make a quick db_populate.js file that will initialize our MongoDB database with some of our delis.

const db = require('./db.js');
const data = require('./delis.js');

db.connect().then(function (db) {
    db.collection('delis')
        .insertMany([
            data.margon,
            data.juniors,
            data.melt_shop,
            data.piccolo,
            data.toasties
        ],
        function (err, r) {
            console.log("Database setup with delis.");
            process.exit(0);
        });
});

Now from the terminal we can run node api/data/db_populate.js to populate our database. And if we look at our database in Compass, there's our data. Leafie is feeling very heroic, and so should you!

Weapons, Tools and Resources

• MongoDB Compass - A GUI interface for MongoDB exploration

Concepts

Helpful Hints

You are Here - Quests

	Quest	Description
	Quest Zero	First quest to read. Provides some overview information and background.
	Quest 1	Initialize your project and install some of the required software.
	Quest 2	creating a quick test JavaScript.
	Quest 3	Crafting your own tools: Building a server process using httpd and express
	Quest 4	Building Your App
	Quest 5	Defining the data for our application
>	Quest 6	Enter MongoDB - Native JavaScript
	Quest 7	Creating and Reading data using the Native MongoDB Driver
	Quest 8	Mongoose - Object Data Modeling
	Quest 9	Creating and Reading data using Mongoose

Next Quest

Next quest: Quest 7 - Creating and Reading data using the Native MongoDB Driver