<div><h4>What is Jenkins?</h4><p>Jenkins is a powerful application that allows continuous integration and continuous delivery of projects, regardless of the platform you are working on. It is an open-source automation server that is written in Java and finds its use in automating the non-human part of the software development process with continuous integration and encourages technical aspects of continuous delivery.</p><p>With Jenkins, organizations can accelerate the software development process by automating the build and testing at a rapid rate. With more than four hundred thousand installations and increasing every day, Jenkins is a widely used application around the world. One of the key advantages of Jenkins is that it requires little maintenance and has a built-in GUI tool for easy updates.</p><p>Jenkins also provides a customized solution as there are over 400 plugins to support building and testing virtually any project. It manages and controls the complete software delivery processes throughout the entire lifecycle, building, testing, documenting the software, deploying, and other stages of a software development life cycle.&nbsp;</p><h4>What is Continuous Integration?</h4><p>In Continuous Integration after a code commit, the software is built and tested immediately. In a large project with many developers, commits are made many times during a day. With each commit code is built and tested. If the test is passed, build is tested for deployment. If deployment is a success, the code is pushed to production. This commit, build, test, and deploy is a continuous process and hence the name continuous integration/deployment.&nbsp;</p><p>A Continuous Integration Pipeline is a powerful instrument that consists of a set of tools designed to host, monitor, compile and test code, or code changes, like:</p><ul><li>Continuous Integration Server (Jenkins, Bamboo, Cruise Control, TeamCity, and others).</li><li>Source Control Tool (e.g., CVS, SVN, GIT, Mercurial, Perforce, ClearCase and others).</li><li>Build tool (Make, ANT, Maven, Ivy, Gradle, and others).</li><li>Automation testing framework (Selenium, Appium, TestComplete, UFT, and others).</li></ul><div class="bigdata-services-area p-5 mb-5 bg-eef6fd"><div class="row"><div class="col-lg-6"><div><h4>Real-word case study of Continuous Integration</h4><p>I am sure all of you aware of old phone Nokia. Nokia used to implement a procedure called nightly build. After multiple commits from diverse developers during the day, the software built every night. Since the software was built only once in a day, it's a huge pain to isolate, identify, and fix the errors in a large code base.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br><br>Later, they adopted Continuous Integration approach. The software was built and tested as soon as a developer committed code. If any error is detected, the respective developer can quickly fix the defect.</p></div></div><div class="col-lg-6 pt-20 pr-30 pb-20"><img src="/uploads/j2_43f12d9482.jpg" alt="" caption=""></div></div></div><p>&nbsp;</p><h4>Benefits of Continuous Integration</h4><p>Spot any integration challenges right away. The small change sets help in easy detection of Integrations bugs.</p><ul><li>Increase Your Code Coverage with less number of changes.</li><li>Build Stuff Faster and never ship broken code.</li><li>Consistency of Build Process.</li><li>Increases confidence in the software. Metrics generated from automated testing and CI (such as metrics for code coverage, code complexity, and features complete) focus developers on developing functional, quality code, and help develop momentum in a team.</li></ul><h4>What is Continuous Deployment?</h4><p>It is the process of automating the code delivery tasks from development to production environment consisting of version control management, deployment on each environment followed by automated testing, and taking decisions based on the results of the previous step.</p><p>So, once code passes through all the stages of compiling the source code, validating the source code, reviewing the code, performing unit and integration testing, and packaging the application continuously, it will then be deployed onto the test servers to perform user acceptance tests. Once that is done, the software will be deployed onto the production servers for release. This is said to be continuous deployment. If you can set up a project server once, you can set up Jenkins to deploy that project again and again as you develop, maintain, and expand it.</p><h4>Benefits of Continuous Deployment</h4><p>The Do-It-Yourself need for Continuous Delivery is eliminated and thereby increasing the focus on the product.</p><ul><li>Ship both cloud-native and traditional applications in a unified pipeline.</li><li>There is a shift of focus onto actual testing as the repetitive tasks are automated.</li><li>Create workflows across the development, testing, and production environments.</li><li>Fault isolation is simpler and quicker.</li></ul><h4>What is Continuous Delivery?</h4><p>Continuous delivery (CD) is a software release approach in which development teams produce and test code in short cycles, usually with a high degree of automation. The goal of Continuous Delivery is to keep software release-ready and enable a repeatable, reliable way to deploy software to any environment. It aims to make feedback loops as short as possible to improve software quality.</p><p>Continuous Delivery takes Agile to its logical conclusion. It is an extension of continuous integration to make sure that you can release new changes to your customers quickly in a sustainable way. Continuous Delivery involves all dimensions of your R&amp;D and Operations organizations - consisting of Team Collaboration, Agile, and DevOps practices, Continuous Integration (CI), Build Automation, Test Automation, Deployment Automation, and Shared Visibility.</p><p>With continuous delivery, you can decide to release daily, weekly, fortnightly, or whatever suits your business requirements. It becomes easy to continuously adapt software in line with user feedback, market shifts, and business strategy changes through low-risk and reliable releases. This helps developers more thoroughly validate updates and preemptively discover issues.&nbsp;</p><div class="bigdata-services-area p-5 mb-5 bg-eef6fd"><h4>Benefits of Continuous Delivery</h4><ul><li>CD facilitates and encourages shorter delivery cycles.</li><li>Faster Feedback and Lean.</li><li>Productivity increases when tedious and repetitive tasks, like filling out a bug report for every defect discovered, can be performed by pipelines instead of humans.</li><li>Minimize Risk.</li><li>CD provides the business with more flexibility in how it delivers features and fixes.</li></ul><h4>What can Jenkins do?</h4><ul><li>Generate tests reports.</li><li>Integrate with many different version control systems.</li><li>Push to various artifact repositories.</li><li>Deploy directly to production or test environments.</li><li>Notify stakeholders of build status.</li></ul><h4>How Jenkins works?</h4><div style="font-size:17px;margin-bottom:10px;margin-top:-7px;"><strong>Setup:</strong></div><p>When setting up a project in Jenkins, out of the box you have the following general options:</p><ul><li>Associating with a version control server.</li><li>Triggering builds based on environment variable like Dev, QA, Stg, UAT and Prod.</li><li>Execution of shell scripts, bash scripts, Ant targets, and Maven targets.</li><li>Publish Junit test results and trigger email notifications about build results.</li></ul><div style="font-size:17px;margin-bottom:10px;margin-top:10px;"><strong>Building:</strong></div><ul><li>Once a project is successfully created in Jenkins, all future builds are automatic.</li><li>Jenkins executes the build in an executer. By default, Jenkins gives one executer per core on the build server.</li><li>Jenkins also has the concept of slave build servers for building on different architectures and distribution of load.</li></ul><div style="font-size:17px;margin-bottom:10px;margin-top:10px;"><strong>Reporting:</strong></div><ul><li>Jenkins comes with basic reporting features like, keeping track of builds status.</li><li>Also greatly enhanced with the use of pre-build plugins<ul><li>Unit test coverage</li><li>Test result trending,</li><li>Findbugs, Checkstyle, PMD</li></ul></li><li>The main page provides a summary of the projects a quick view of<ul><li>What building (No builds in the queue)</li><li>Build Executor Status(both Idle)</li><li>Status of the projects.</li></ul></li><li>Project status pages provide more details about a given project&nbsp;&nbsp;<br><ul><li>The status of the last several builds&nbsp;</li><li>Charting (depending on plugins)&nbsp;</li><li>Dependencies</li></ul></li></ul></div><h4>Conclusion</h4><p>Continuous integration is a necessity on complex projects due to the benefits it provides regarding early detection of problems. A good continuous build system should be flexible enough to fit into pre-existing development environments and provide all the features a team expects from such a system.</p><p>Jenkins, a continuous build system, can be an integral part of any continuous integration system due to its core feature set and extensibility through a plugin system.</p></div>