Prerequisites

Step 0.5

Before installing node (Mac)

To compile node we need gcc, make and git to import node source code.

$ brew install git

• Install Xcode 
• Install Hombrew
• Install git

Step 1

Clone Node's Git repository

Cloning node.js source code:

$ git clone git://github.com/joyent/node.git

Step 2

Compile & install Node.js

Go into the newly created node folder and install node

$ cd node
$ git checkout v0.12.4    
$ ./configure
$ make
$ sudo make install

<-- recommended version

Step 3

Add user´s directory to BIN Paths

Open the sudoers file

$ sudo su
$ nano /etc/sudoers

Inside the editor scroll to where you see the line: 

Defaults secure_path = /sbin:/bin:/usr/sbin:/usr/bin

Append :/usr/local/bin to the end so it should appear like: 

Defaults secure_path = /sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin

Step 4

Install npm

Download and install npm

$ git clone https://github.com/isaacs/npm.git
$ cd npm
$ sudo make install

npm stands for Node Package Manager and is useful tool when developing in node to easily manage packages and dependencies for a node project

Step 5

Testing Node & npm

Test that node and npm are installed

$ node -v
$ npm -v

Step 6

Installing Express

Install express and express-generator globally

$ npm install -g express
$ npm install -g express-generator

express-generator, as the name says, will generate an express application's skeleton for us with some boiler-plate code.

Your first app

(Yes it will be a Hello World app)

Step 1

Create node/express projects folder

Create the project's folder and go into it.

$ mkdir node-express
$ cd node-express

Step 2

Create the express project

Run the express command to create an express project.

$ express hello-world
$ cd hello-world

This will create a folder called hello-world that contains the basic components of an express project.

Step 2.5

The components of an express project

• app.js - This file acts as the main driver for the project.
• package.json - This file stores the dependencies/packages for the project.
• bin - Has the start up script for the project.
• public - This folder holds public files like stylesheets and scripts.
• routes - Holds the possible routes (urls) for the project.
• view - Holds the HTML (or Jade or ejs) files for the project.

Step 3

Installing project dependencies

Once the project has been created we now need to install the dependencies.

$ npm install

This will create a node_modules folder that will house all of our local project packages, based on our package.json file.

Step 4

Understanding the app.js file

The app.js file is the heart of our application and can be broken down into various sections.

The first section defines some variables based on installed packages and even sets some routes based on ones given to us by express. In the last line we instantiate express and assign i to an app variable.

Step 4 cont'd

Understanding the app.js file

The next section tells the app where to find views what engine to use to render them and calls some methods to get the app prepared to run effectively. It also defines a few routes and tells the app what files to use for each. We recommend visiting the Express site to learn more about these methods.

Step 4 cont'd

Understanding the app.js file

The next section focuses on error handlers for development and production telling the app to print out error information when in development mode. We are not too worried about these for now.

Step 4 cont'd

Understanding the app.js file

The last line exports our app variable so it can be called and used in other files.

Step 5

Writing our hello world code

Navigate to our routes file and open the index.js file.

Lets change our title variable to 'Hello World' and then lets open our index.jade file in our views folder.

Step 5 cont'd

Writing our hello world code

This file is written in Jade and calls our layout page as a type of master page.

Lets change our line 5 to read 'p Welcome <your name>'.

Step 6

Running & viewing our application

Before we can run our application, we must tell it which port to listen on. Add the following lines to the end of your app.js file.

Finally, we can run our app by navigating to our project's folder (hello-world) and running the following command.

$ node app.js

Step 6 cont'd

Running & viewing our application

Your console should look like this.

We can now navigate to our browser and view our application at localhost:3000.