Many big corporations who have a massive audience on their web front have to update their system quite frequently; sometimes several times a day. In order to keep up with such concurrent changes, software developers need a specialised infrastructure and tools to quickly execute, test and deliver. That is exactly what Jenkins is made for – Continuous Integration (CI) and Continuous Delivery (CD) all the way!
What is Jenkins?
Jenkins can be defined as a continuous CI/CD server written in Java. It simplifies the building of projects through automation of numerous tedious tasks. It is a free open source platform that can be used for self-hosting software applications. Jenkins was invented by Kohsuke Kawaguchi in 2004 was entitled as ‘Hudson’ back then. Getting tired of broken code, he believed that CI would help test his code before submission and save him from routinely humiliation – he was right! Soon his colleagues wanted in so he open sourced the project, and from there it spread out.
CI & CD
CI is a process that aims to speed up the software development cycle via compilation of the team’s code and automated unit/integration testing. It is the best practice for developing quality software, as it helps eliminate most bugs or errors in the preliminary stages. It implies an environment where contribution from every developer is monitored, code is verified and all operations are streamlined.
CI runs on a shared server so that all team members can be informed of any minor or major changes made in the project’s base code. One can also configure alerts for when someone submits faulty code that needs to be revised. Developers can set up a series of tests and choose different levels of testing automation for their software. While CI compiles and tests the entire application, CD pushes the application towards a repository so it is ready for deployment. Through Continuous Delivery, features or versions of an application are transferred to the client, end user or manual testers during early testing, as well as throughout the development process.
Why Use Jenkins?
The average DevOp team is hardly a team; unfortunately it’s a number of confused people working independently or in smaller groups. The lack of togetherness among the whole team often leads to a fragmented workflow. The array of incompatible and clashing pieces delays the final product. Also, everyone ends up annoyed and hating each other’s guts. When multiple individuals contribute to something separately, the outcome can be complex and problematic. As a result, the whole cycle becomes sluggish while a lot of valuable time and resources are spent on laborious debugging. These kind of situations call for a solution like Jenkins, which utilizes a constant integration and delivery method.
Pros of Jenkins:
- Free and open source
- It can easily be installed and configured from its user friendly web GUI
- It integrates with every OS and SCM
- It supports building with Maven, Ant, Gradle, JUnit, Nexus, and Artifactory
- It is compatible with other languages apart from Java; it supports C/C++, Python and PHP tools etc.
- It offers 1000+ plugins (mostly free); fairly extensible
- Basic knowledge of Java is enough to learn Jenkins
- Real-time reports
- Highly customizable
- Lets you design your own plugins
- Supports a distributed network
- It collaborates with multiple repositories
- Self-hosted; control over data
Cons of Jenkins:
- It is not a modern tool
- The UI is dull
- It must run on a server so costs apply
- Requires manual updation and maintenance
- Takes time setting up
- Writing tests is a basic requirement
Implementing Jenkins or a CI/CD approach can be challenging for developing teams who are not adhered to coordination. It requires a cultural shift within the workplace, especially within the management staff. Most software agencies that are juggling with multiple projects and working on tight deadlines, may see it as a hindrance. All the time/resources put into setting up and operating the system is often seen as unproductive work. What agencies fail to comprehend is the return of investment which includes cleaner code, better product, and ultimately costs associated with fixing errors later on.