CI tool

What is a CI tool? Well, it is nothing more than an orchestrator. A CI tool is at the center of the CI system, connected to the Version Control System, build tools, Binary Repository Manager tool, testing and production environments, quality analysis tool, test automation tool, and so on. There are many CI tools: Build Forge, Bamboo, and TeamCity, to name a few. But the prime focus of our book is Jenkins:

Centralized CI server

A CI tool provides options to create pipelines. Each pipeline has its own purpose. There are pipelines to take care of CI. Some take care of testing; some take care of deployments, and so on. Technically, a pipeline is a flow of jobs. Each job is a set of tasks that run sequentially. Scripting is an integral part of a CI tool that performs various kinds of tasks. The tasks may be as simple as copying a folder/file from one location to the other, or they can be complex Perl scripts to monitor machines for file modifications. Nevertheless, the script is getting replaced by the growing number of plugins available in Jenkins. Now you need not script to build a Java code; there are plugins available for it. All you need to do is install and configure a plugin to get the job done. Technically, plugins are nothing but small modules written in Java. They remove the burden of scripting from the developer's head. We will learn more about pipelines in the upcoming chapters.