What is Continuous Integration?

The process of Continuous Integration is central to the DevOps implementation. It includes automating the building and testing of the code every time the changes in the code are done. The methodology of continuous integration lets you share the code and unit test by making the changes in the shared version control repository. This way anybody can get the latest version of the code.  It helps to build, test and validate the complete process.

Table of Contents

• What is Continuous Integration?
• How does Continuous Integration make working so easy?
• Top tools for Continuous Integration
• How Continuous Integration works?
• Continuous Integration Vs. Continuous Deployment
• Advantages of Continuous Integration
• Conclusion

Don’t miss out on our DevOps training video! Learn from industry experts and gain the skills you need to succeed in today’s fast-paced software development environment:

What is Continuous Integration?

Continuous Integration is the process in software engineering that is being extensively used in the DevOps methodology to isolate the changes so that they can be immediately tested and reported when they are added to the larger code base. Continuous Integration strives to provide rapid feedback which helps to detect any bugs or defects in the code base so that it can be noticed and rectified at the earliest. It is possible to automate the testing using the tools of continuous testing software tools. The aim of CI was to bring together extreme programming principles, ushering in an iterative development model. At first, daily builds were the norm, but CI has evolved to enable even more frequent code submissions for rapid, efficient builds. This early bug detection saves significant time and resources, as fixing issues becomes increasingly complex and costly in later stages. In simple terms, Continuous Integration minimizes expenses and simplifies the development process.

It is possible to take advantage of the modern version control system like Git which is useful in creating short-lived branches to isolate the work. There is a pull request by the coder after the completion of the feature and on the pull request getting approved, the changes get merged into the master branch. Once this is done the previous feature branch can be deleted. The process is repeated by the development team for extra work. Branch policies can be established to see the master branch is as per the desired criteria.

Every commit to the master branch will trigger the automated building and testing process. When the bugs are caught early on in the stage of the development cycle it is relatively inexpensive and continuous integration ensures this is possible. The automated tests that are run on every build will take care of maintaining the consistent quality of the build.

“Thanks to practices such as Continuous Integration, Continuous Delivery and DevOps, high performers are often now doing thousands of production deployments daily!” – Gene Kim.

 Some standard practices of a continuous integration process include the following :

• Frequently committing the code to the code base
• Having an integration build machine that is dedicated
• Having a feedback mechanism that is also continuous
• The developer tests are specifically grouped.

How does Continuous Integration make working so easy?

The purpose of Continuous Integration was to use it in combination with the automated unit tests that are written using the practices of test-driven development. This meant that the unit tests were run in the developer’s local environment and ensuring that it passed before it was committed to the mainline. This way it is possible to make sure that one developer’s work in progress won’t hinder the copy of another developer’s work. It is possible to disable the partially complete features before the commit is done.

The process of CI included the introduction of the build server in the later stages which automatically ran the unit tests on a regular basis or even after the completion of each commit and results are reported to the developer.

For automating the unit tests, the organizations use a CI methodology that is typically done using a build server to implement the continuous process for the application of the quality control. It includes the small pieces of effort that are applied frequently in order to make the process of CI successful. This type of process is used for running the unit and integration tests along with running the static and dynamic tests. It is possible to extract and format the documentation process and measuring and profiling the performance from the source code and facilitate the process of manual quality assurance. So the Continuous Integration methodology can also be applied to the QA process.

When you are working with continuous integration the next step would be logically the continuous deployment which is extending the benefits of continuous integration to the deployment stage so that the actual deployments can be made.

Top tools for Continuous Integration

• Jenkins : An open-source, cross-platform tool written in Java. Known for its flexibility, it offers both GUI configuration and console commands. Extensively customizable through various plugins. Jenkins is a widely adopted CI/CD solution due to its strong community support and vast integration capabilities.
• Bamboo : Developed by Atlassian, available as a cloud and server version. Supports other Atlassian tools like BitBucket and JIRA. Bamboo is particularly favored for its seamless integration with the Atlassian suite, providing an end-to-end DevOps ecosystem.
• Apache Gump : Assists in building and compiling software code, identifying incompatible changes as they’re introduced into version control systems. Apache Gump is valued for its early error detection and automatic build management features.
• CircleCI : Hosted on GitHub, supports a range of programming languages and leverages containers for efficient service delivery. CircleCI is preferred for its cloud-native approach and robust language support.
• Buildbot :  An open-source tool supporting automation of integration, building, and testing processes. Compatible with various operating systems. Buildbot is highly customizable and adaptable to a variety of environments and tools.
• TeamCity : Java-based tool supporting multiple platforms and providing integration with popular IDEs like Eclipse and IntelliJ. Offers numerous free plugins. TeamCity stands out for its strong Java support and excellent integration capabilities.
• Travis CI :  An open-source tool hosted on GitHub, supporting multiple languages and being platform-independent. Applications are built within virtual machines. Travis CI is recognized for its open-source nature and seamless GitHub integration.

How Continuous Integration works?

When developers are working on the process of continuous integration each developer will take a copy of the current code base in order to initiate the work. As and when more developers will be submitting their change to the code in the source code repository it is obvious that the copy does not look like the original one in the repository code. This changed copy can not only accommodate the change in existing code base but also new code can be added to the same along with the addition of new libraries as and when needed.

The more time it takes for a certain section of the code to remain outside of the repository the tougher it is to resolve the various conflicts that occur due to multiple developers try to integrate it back into the repository. When the developers want to submit code to the repository they have to update the code so that the changes in the repository are reflected from the time they took the copy of the code.

The higher the amount of changes in the repository the bigger the amount of work that the developers have to do in order to submit the changes that they have made into the repository. The main aim of continuous integration is to prevent the problem of continuous integration hell which is defined as the time it takes to integrate the code is more than what it takes to make the original change. Hence the most important thing is to integrate early and integrate more often.

There are organizations that have a slightly different version of working with Continuous Integration i.e. before submitting the work they must do a complete build and run test and also ensure that the code passes the test. Such kind of tests can be run on a Continuous Integration server automatically as and when it detects a new code commit.

Continuous Integration aspires to have the process in place so that the new and changed codes are existing in the code repository and that there is no time lapse between the commit and build. This precludes the need for errors that might arise without the developers being able to notice and correct it. Continuous Integration gives the benefit of triggering the builds thanks to every commit in the repository instead of having to periodically having to do the build scheduling. This type of automation will ensure that whenever there are multiple developers that are rapidly committing the codes it is possible to have a trigger in a short time after each commit and then deploying a build when the timer has expired. This type of scheduling is available in a lot of the automation tools.

Continuous Integration Vs. Continuous Deployment

Difference between Continuous Integration and Continuous Deployment is important in the software development domain. This section explores the differences that set these two practices apart, helping you grasp their unique roles in the development process.

Advantages of Continuous Integration

Continuous integration comes as a boon to the software development community. It has redefined the age-old practices of building software and deploying it to client in a whole different way. Some of the obvious benefits of Continuous Integration are as follows:

• It improves the developer’s productivity
• It helps to find the bugs faster
• It is possible to deliver the updates faster
• There are no surprises at the end as there is no incompatibility
• There is feedback on the local changes made throughout the system
• Automate the build and make the build self-testing
• There are no long and tense integration processes
• Check the feasibility of the code without having to wait
• Consensus when it comes to frequently automated testing
• The latest version of testing, demo and release is always available
• Codes are modular and less complex thanks to frequent check-ins
• Less time debugging and more time adding new features
• Dedicated integration build machine and continuous feedback system.

Conclusion

In this exploration of Continuous Integration, we’ve uncovered the transformative role it plays in modern software development. Continuous Integration simplifies the integration of code, promoting collaboration and ensuring that software remains flexible and error-free. By accepting Continuous Integration, development teams can enhance efficiency, reduce errors, and accelerate software delivery. This powerful approach not only facilitates a more dynamic and adaptive development process but also empowers teams to meet the ever-evolving demands of the digital age. Continuous Integration is more than a technique, it’s key to providing secure software in an adaptable and efficient manner, ensuring that you stay at the top of the software development domain.