Quick Tip: Installing NodeJS 8 on CentOS 7

Node JS has been gaining more popularity as the server-side runtime environment of choice these recent years. The asynchronous event-driven feature built into Node JS can be considered a killer feature that may flatter a system architect planning to build a high-performing server-side component serving HTTP webservice to the clients.

Node JS is cross-platform. The executable can run on major OSes that include Windows, GNU Linux, and Mac OS. Having a wide OS support further accelerates Node JS adoption within the server-side technology stack. Continue reading

Using SCP to Securely Upload Files and Directories to Remote Server

Secure Shell (SSH) is a common protocol used to access or login to remote servers. The protocol is widely supported across Operating Systems. If you are Windows user, you may have heard and been using Putty, which is a SSH client for Windows. Windows 10 users can use Open SSH client that can be installed via new feature installation. UNIX OSes usually come with native SSH client support, so additional software installation is not needed. Continue reading

How To Install Docker on Ubuntu 16

Docker is a popular option for “virtual appliances” nowadays. Docker website defines the “Docker” moniker as a software containerization platform that is more flexible than traditional virtual machines since it virtualizes the operating system instead of the hardware. This means that Docker can further isolate the resources by enabling multiple Docker containers running on an operating system. If the operating system itself is running on a virtual machine either via full virtualization (bare metal) or paravirtualization, we will have a good example of IT infrastructure transformation from asset-ownership model into cloud-lease model (my related paper about such transformation can be read here). Continue reading

Xpath Basics: Introduction to XPath with an Example Java Project

xpathXPath is a W3C recommendation used to search and find parts of an XML document through a path expression. The elements or attributes that match the path expression will be returned for further processing by the invoking command, module, actor, or component.

In this post, I will explain about the basic concept of XPath via presentation slides. The presentation starts with a revisit to some of the XML key concepts. Subsequently, it shows sufficient elaboration of the basic concept of XPath. It concisely describes the key features of XPath that are worth knowing and practically useful especially when searching inside XML files.

The final part of the presentation consists of a sample project accompanied with some screenshots provided for readers to experiment with. In an upcoming post, I will show how the sample project can be converted into a Maven project for more convenient use and distribution.

You can download the slides from the following URL:

Xpath Basics (2735 downloads )

Maven Tutorial for Beginners: Installation and Configuration

maven_windowsMaven installation on Windows is very straightforward. Nonetheless, this post will provide sufficient elaboration to ensure a smooth installation. Following the installation, some configuration and testing tasks may need to be completed prior to creating the first Maven project.

A prerequisite for Maven installation is Java JDK. If you have not installed the Java SDK, you can refer to the installation procedure explained in this post.

The installation and configuration steps are executed in order as follows:

1. Download Maven zip package from the download page

Maven download page URL is http://maven.apache.org/download.cgi.
In this post, we will install and configure Maven 3.2.3. It can be anticipated that the installation procedure of the newer version of Maven will be quite similar with the one explained in this article.

2. Extract the zip into an installation directory of preference.

In this article, the directory contained in the extracted zip package is moved into “D:\Devs\DevHome\Maven\Bundle\apache-maven-3.2.3”. There is no strict rule regarding the installation directory. You can put the Maven directory in any directory of your choice. Continue reading