Cloud and Mobile

Setup Node.Js Enviroment on Amazon EC2 linux

By Daniel Du

Node.Js is very popular in web programming, you can use single language - JavaScript - to create the back end logic and the front end web page. Installing NodeJs environment on Mac or Windows is relatively easy, while if I need to put my Node.Js sample into production, I will have to set it up on Linux. Of cause I can choose Windows to host Node.Js application, but I prefer to choose the free Linux, which is a good practice for me as well.

I am using AWS EC2 as my host. Firstly, I need to launch an EC2 instance on AWS. I will use Amazon Linux AMI here.

I’d like to start from t2.micro, which is free tier eligible. Once I find it not powerful enough for my application, I can scale up or scale out easily.

for the 3rd step, I use the default settings:

Step4, add a Elastic Block Storage, I just use the default setting, and I can add another EBS storage latter if necessary.

Step 5, add some tags so that I can recognise this server easier, it is useful especially when you have many instances running.

Step6, Configure the security group, which is similar like firewall on AWS side, which is a whitelist, only allowed port can pass though. My server is supposed to be web server, so I add HTTP/80, and to connect to the server and do some configuration work, I also enabled SSH/22. I can remove this once the configuration is done.

Once I review the instance settings and they are fine for me, now I am ready to launch it. But before that, I need to create a key pair so that I can connect to this serve latter. Be sure to download the .pem file and save it to somewhere secure.

Now, it is ready to go. After a few minutes, my Linux server is up and running.

Now I will connect to it and install the node.Js environment into it. To connect to the EC2 Linux instance, I need a SSH client. For Mac, the built-in terminal is good enough for me, for Windows, you may find Putty useful. Actually if I got the EC2 console, select the instance and click the “connect” button, AWS will tell me how to connect to this server:

To access your instance:

1. Open an SSH client. (find out how to connect using PuTTY)
2. Locate your private key file (aws-ipg-cp-adn-devtech.pem). The wizard automatically detects the key you used to launch the instance.
3. Your key must not be publicly viewable for SSH to work. Use this command if needed:

   chmod 400 aws-ipg-cp-adn-devtech.pem
   

4. Connect to your instance using its Public IP:

   54.67.70.195
   

Example:

ssh -i aws-ipg-cp-adn-devtech.pem [email protected]

As indicated, I connected to my Linux server from my Mac terminal with SSH:

Now I am ready to install Node.Js environment. Firstly run ‘yum update’:

$ sudo yum update

Next, I will go ahead to install node.js from source code:

$ sudo yum install gcc-c++ make

$ sudo yum install openssl-devel

$ sudo yum install git

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

$ cd node

The source code of Node.Js is downloaded to my linux server.

To check out one version of Node, I view all available Node tags with following command:

$ git tag -l

I’d like to use Node 0.10.32, so I check it out with following command, you can choose your favourite version. And then I start installing it from source code, it may take a few minutes to complete.

$ git checkout v0.10.32

$ ./configure

$ make

$ sudo make install

Now my Node is installed on my Linux server :

I also need to install some useful NPM packages, but when I do that, it reminds me that the command is not found.-

$ sudo npm install express

sudo: npm: command not found

[ec2-user@ip-172-31-25-230 node]$

so I need to add it to sudo’s path so that I can install more packages.

$ sudo vi /etc/sudoers

Append the /usr/local/bin to the secure_path as below:

After saving this file and exit to the command line, I can install express and others:

It seems the environment if one, but to confirm,I need to create a very sample Node.Js application to verify the environment works fine.

[ec2-user@ip-172-31-25-230 ~]$ mkdir firstnodeapp

[ec2-user@ip-172-31-25-230 ~]$ cd firstnodeapp/

[ec2-user@ip-172-31-25-230 firstnodeapp]$ ls

I created the Node.Js sample on my local machine and then upload the source code to Linux server. BTW, I use CyberDuck to upload files into EC2 Linux, which is very helpful. Be sure to check “use public key authentication”, it will ask you the *.pem file, which is downloaded from AWS when creating the instance. Once I connect to the EC2 instance from CyberDuck, I can drag and drop files into it to upload them.

A few seconds latter, my files are uploaded, let’s go back to the terminal of EC2 instance to start the Node.Js application.

[ec2-user@ip-172-31-25-230 testnodeapp]$ ls

app.js bin package.json public routes views

[ec2-user@ip-172-31-25-230 testnodeapp]$ npm install

[ec2-user@ip-172-31-25-230 testnodeapp]$ chmod -R +x .

[ec2-user@ip-172-31-25-230 testnodeapp]$ sudo DEBUG=testnodeapp ./bin/www

Now the Node.Js application is running (I am using 80 port when I created the Node.Js sample) , I did not use the default 3000 port because my security group in AWS does not allow it. Yes, I can edit the security group to add 3000 port, but HTTP/80 makes more sense to me for a web server. Now I can now access it from browser. It is just a samplest express site, but the Node.Js environment looks fine now.

Next step, I will create a new AMI based on this instance, I do not want to repeat all these steps every time when I need a NodeJs Linux instance :) Go to the AWS Console, right click the instance and choose Image -> Create Image:

Give it a name:

Now the AMI is being created. if go to Images -> AMIs from left panel, it shows my custom AMIs.

OK, I wil stop here, next I can start up a new instance with Node.Js environment ready by launching an instance from my customised AMI, and more important, I can launch more instances like this to do auto scaling latter.

Trillions – Thriving in the Emerging Information Technology

By Jeremy Tammik.

I just finished reading Trillions – Thriving in the Emerging Information Technology by Peter Lucas, Joe Ballay, Mickey McManus of MAYA Design, distributed to all Tech Summit presenters.

It discusses design and technology for pervasive computing, provides numerous shockingly obvious and often quite old insights, a very critical view of our current use of Internet and so-called cloud technologies, and an inspiring and thrilling read.

The topic is how to harness and live in – as opposed to 'with' – the unbounded complexity of the trillion-node network of connected devices that we are inevitable heading towards, and will lead to catastrophe unless we radically change some fundamental aspects of the ways we handle and share information.

I highly recommend reading this book.

I highly recommend abstaining from all use of the word 'cloud computing' until you have completed it :-)

Debugging Asynchronous CouchDB Callbacks & Snapshots

By Jeremy Tammik.

I more or less completed the research for my cloud-based round-trip 2D Revit model editing project.

Here are the main items in my discussion of that and one or two other cloud and mobile related topics:

• Three aspects of life and programming
• Room editor navigation
• Nested asynchronous database call-back functions
• Roomedit – my first GitHub project
• Debugging JavaScript with Firebug
• Screen snapshots on mobile devices
• Open source components used by Autodesk

Relax – Simple Free Cloud Based Data Repository with NoSQL, CouchDB, and IrisCouch

By Jeremy Tammik.

I searched for a simple cloud-based data repository option and found one that seems simpler and more transparent than the Microsoft Azure and Amazon solutions discussed here so far: NoSQL, CouchDB, and IrisCouch.

Check it out, and please let us know what you think of this alternative!

Interesting Google I/O Announcements

By Gopinath Taget

The Google I/O event is currently underway at San Francisco and I would have loved to be there. However, the event tickets sold out very fast and was not quick enough .

In any case several interesting announcements have been made so far like the availability chrome browser for Apple devices like the iPhone and iPad, the Nexus 7 tablet, the Nexus Q Media Player and the latest and greatest update to the Android OS code named Jelly Bean (Android 4.1). However, the most interesting announcement for me was that of the Google Compute Engine. You can read more about it here. Its not public yet and is still in a preview stage.

Up until the announcement of the compute engine, the only Google based cloud platform that allowed running custom applications on the cloud was the Google App Engine. But the App Engine was a black box. It allowed you to build “business applications”and websites using Java and Python but did not give access to the underlying software or hardware infrastructure that executed these applications. Google promised that you don’t have to worry about issues like scaling or other infrastructure issues you encounter typically for web based or network based applications. If you were OK with this lack of control, the GAE was an ideal platform for development.

With Google Compute Engine, Google tries to please the control freaks among us who pray at the alter of cloud infrastructure providers like Amazon Web Services and Windows Azure. With the compute engine Google promises greater control on scaling, performance and access to large compute clusters on Google’s Infratructure. It mainly offers access to Linux based operating systems. It also offers command-line tool as well as a rich REST based API to manage this compute infrastructure. If you have not done so already, I would suggest that you sign up for access to the limited preview of the Google Compute Engine.