Thursday, 8 March 2018

Adding node.js applications to an existing LAMP installation

So you've already been developing lots of LAMP applications on your local server. You've moved into creating node.js applications. You want to continue, as before, with your LAMP applications, but add node.js applications in the same directories i.e /var/www/html/ and so on.
In that case you need to add a little to your Apache setup to help in this process.

Prepare Apache

In your /etc/apache2/apache2.conf file:
Make sure these 2 lines are uncommented (or even exist)
LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_http_module modules/mod_proxy_http.so
Now add the following (it can be at the end if you like)
ProxyPass /mynodesite http://localhost:8000

Restart Apache

systemctl reload apache2

Create the application file

Create a file in /var/www/html/mynodesite called app.js and insert the following:
var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World!\n');
}).listen(8000, '127.0.0.1');

Run the app

node app.js

Now the browser

Open the browser with the address http://localhost/mynodesite
Hey presto!

Saturday, 24 February 2018

How to add a directory to your path in Ubuntu

Open up the terminal
Type the command
echo $PATH
This gives you the current path.
Let's say you want to add the directory /home/mick/temp to the path...
Copy the current path you have just echo'd. Lets's say it's
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin
First make sure you are in your home directory by typing
cd ~
Open the file .bashrc using an editor such as gedit using
gedit .bashrc
Go to the bottom of the file and add a line
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin
Where the existing path is just pasted in.
Now add a colon followed by the path you'd like to add so that it reads
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/home/mick/temp
Save the file and restart your computer.
Now any excecutable placed in can also be available wherever you are on your installation.
This will be useful in following blog entries.

The 2018 Web Developer : Adding node_modules to a project using npm

In the last post, I prepared the ground for adding node_modules to my project. In my simple, learning project I'm going to add 3 modules:

  • bootstrap
  • jquery (which bootstrap needs)
  • popper.js (which bootstrap 4 also needs)

First open the project within the atom browser. Then I open the terminal within the browser (which sets the current working directory to my project). Within the terminal I type:
npm install bootstrap
npm install jquery
npm install popper.js
Job done! Well not quite. The start page for my project is taken from the Twitter Bootstrap starter template. So I now need to change the paths of the scripts and CSS links to :
<link rel="stylesheet" href="node_modules/bootstrap/dist/css/bootstrap.min.css">
<link rel="stylesheet" href="scss/custom.css" />

<script src="node_modules/jquery/dist/jquery.min.js"></script>
<script src="node_modules/popper.js/dist/umd/popper.min.js"></script>
<script src="node_modules/bootstrap/dist/js/bootstrap.min.js"></script>
Now I'm cooking with gas. I can also start employing the SASS elements of Twitter Bootstrap.

What next?

There is much greater power in using node.js, nvm and npm, but it's a good start.

The 2018 Web Developer : Preparing a project for node_modules using npm

To prepare my project for node modules, I must initialise node within it's root directory.
First change to the project directory, using:
cd /myproject
Then type:
npm init -f -y
This will avoid me answering awkward questions that I'm not sure of, and provide me with a package.json file.
I'm also going to use the opportunity to make sure I'm got some tools in place such as the atom text editor, the slimjet browser and the LiveStyle plugins for atom and Chrome (which we can use in Slimjet).

atom

I won't go through the reasons for using atom, you can get that from many places, but needless to say I'm convinced. To install on Ubuntu:
sudo add-apt-repository ppa:webupd8team/atom
sudo apt update; sudo apt install atom

I had a graphic problem on an old laptop. It kept flashing. To remedy this I changed the command of my Atom launcher to:
/opt/atom/atom --disable-gpu
I installed the platformio-atom-ide-terminal package. This will open up a terminal inside the editor. It's quite useful because some commands, such as node-sass.
I also installed the livestyle-atom package.

Slimjet

Slimjet is a slim, fast browser which will give me all the benefits of Google Chrome browser by using its engine, but without telling Google everything I'm doing. To install:
wget http://www.slimjet.com/release/archive/8.0.4.0/slimjet_amd64.deb
sudo dpkg -i slimjet_amd64.deb
Now to add the livestyle extension. Within the browser:
More tools->Extensions->Get more extensions
Type livestyle

LiveStyle

LiveStyle is a tool for live CSS editing. It means I'll be able to edit my SASS file and see the changes in real-time within the Slimjet browser.

What next?

I now have some good tools in place for my project. I have a fast browser. I have an editor which allows me to make SASS changes and see them in real-time. I can do this by opening a terminal and starting the node-sass package. I can also use the terminal to compile changes to my .js files using node. I can also use the terminal to initialise my project to be node ready.
Now I can start adding local node_modules to my project in the next post.

The 2018 Web Developer : Adding node-sass globally

In the previous post I installed node.js (node). This also came bundled with the Node Package Manager (npm). npm allows me to install many packages created by the JavaScript community, both open-source and commercial. Examples include Twitter bootstrap, ReactJS, etc.
In this example I'm going install use node-sass, globally. This will allow us me develop CSS for any project using SASS on my system using.
From the command line type:
npm install -g node-sass
I then test that it has installed using:
node-sass -v

Using node-sass

In this first example, I have a terminal window open and I'm in a directory containing my custom.scss which will need compiling to custom.css in order to be used by my web pages.
node-sass -w custom.scss custom.css
In this second example, I'm in the root directory of my project with a subdirectory of /scss. Here, I am compiling all .scss files to their .css equivalents, in the same directory.
node-sass -w scss/ -o scss/

What next?

Now that I have used npm to install a package globally. I've applied a package, namely node-sass, which will improve my productivity. Now, in the next post, I need to begin a new project and prepare the ground for project specific packages.
I'm also going to use the opportunity to make sure I'm got some tools in place such as the Atom text editor, the slimjet browser and the livestyle plugins.

The 2018 Web Developer : Install node.js (node) on Ubuntu

In the last entry of this series, I installed Node Version Manager (nvm). This was important in order to give me the flexibility I need in this entry.

What is node.js (node)?

According to wikipedia "Node.js is an open-source, cross-platform JavaScript run-time environment for executing JavaScript code server-side".

How will node help me?

The first pleasure I got for using node.js was in testing JavaScript I'd written through the terminal. This meant, I could edit a file such jimmy.js, then test it on the command-line through:
node jimmy.js
No need to keep refreshing a browser. It also provided me with warning and error messages like any other compiler.
node also opens the door to much bigger things, particularly through the Node Package Manager, which I'll discuss in future posts. So it's well worth having.
Now to install node.js using nvm
nvm install node
Test that it has installed using:
node -v
If, for any reason, this call returns an error; node may not be in your PATH variable. To rectify this, open your .bashrc file, and at the bottom, add the line.
PATH=/usr/bin/node:$PATH

What next?

Now that I have nvm, npm and node installed what can I do?
Well I can begin by using node as a compiler for .js files. I mention this in the section titled "How will node help me?". I use the atom editor, which I'll be referring to in this series. So if I install the platformio-ide-terminal in atom, you can imagine how quick I'll be editing .js files now.
However, it's also good to know that I will face other, better improvements in my productivity with this new tool set. In the next post, I'll use npm to install node-sass globally. This will allow me to develop using SASS on all my projects.

Friday, 23 February 2018

The 2018 Web Developer : Install nvm on Ubuntu

In the introduction to this series I wrote about the value of learning JavaScript technologies such as node.js (node), in order to avail myself of more work. In order to install node I should first install nvm. This will allow me to control the versions of I install.

What is nvm?

Node Version Manager (nvm) is a tool for applying node to an installation.

How will nvm help me?

Let's say you're involved in a project which began and continues to be running using an older version of node. You, as a developer need to be in a position to install that older version in your project. You would obviously, also want to install newer versions for other projects.

OK, I'm convinced. Let's install stuff

Let's begin with nvm.
From your home directory, create a directory called .nvm
mkdir .nvm
sudo apt-get install build-essential libssl-dev curl git-core
curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.8/install.sh | bash
Check the latest version from https://github.com/creationix/nvm
Now reboot and check that it works using:
nvm --version
A new directory should have been added to you home directory called .nvm
And the following should have been added to your .bashrc file
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"  # This loads nvm
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion"  # This loads nvm bash_completion

What next?

I haven't achieved much here, other than installing a piece of software, but I have opened the door to the possibilities which node brings. In the next instalment I'll take another baby step. I'll use my newly installed piece of software to install node.