This is a guest post for the Computer Weekly Developer Network in our Continuous Integration (CI) & Continuous Delivery (CD) series.
He says that says that CI/CD has meant that in large organisations, where the software deployment process once took days, today, an entire build and test processes each take about five minutes — and when deployments are triggered they take about an additional 10 minutes.
Sinha writes as follows…
Amazon managed to decrease the number of simultaneous outages and increase revenue by releasing code every 11.7 seconds on average. Netflix isn’t as fast – its developers release code only several times a day, yet it still manages to adjust to its customer’s needs.
What this means is that CI/CD has most impact on products that need regular feature updates and at the same time need continuous fixes for bugs.
In other words, when changing code is routine, CI/CD is an efficient way of developing software enabling more frequent, meaningful and faster deployments releasing updates at any time in a sustainable way.
CI/CD pipeline is a connected sequence of development process broken down into different stages and helping developers to get a quick feedback at different levels. CI is the first stage of the pipeline laying the foundation for continuous delivery and continuous deployment stages.
- Continuous Integration = Build, Test, Merge
- Continuous Delivery = Automatically release to repository
- Continuous Deployment = Automatically deploy to production
- Continuous Integration = The process to build codes and test them automatically. It makes sure that all the changes are regularly collected automatically.
Successful CI is a branch that helps individual software developers to make new code changes frequently (or on a daily basis) to the app and integrate those changes into a shared repository without breaking or conflicting the existing code of the application.
It enables multiple developers to work simultaneously on different features of the same application and merge it with the existing codes at the common place.
Post code merger, the updates are validated by automatically building the application and running automated tests at various levels of the entire application. This ensures that the new code changes have not broken the existing codes. If any conflict is discovered during the automated testing, CI helps to do away with those conflicts by fixing those bugs quickly and often.
Continuous delivery is a process that picks up from the point where CI ends. It is a way to allow the teams to release the updates from the main repository to customers. The regular continuous delivery that can be monthly, weekly, daily or as early as possible helps to streamline and automate the whole process through training and retraining, laying the foundation for continuous deployment.
Continuous deployment is nothing but an automated version of continuous delivery. Post continuous delivery stage the new changes are released to the customers through automation. It helps to eliminate the risk of human error and only an unsuccessful test can prevent the new changes from going through.
Such automation allows the development team to do away with release day pressure. This automated process built through training and retraining helps to deploy the changes at a click of the button. Release of code changes as soon as possible is advisable, as making fixes in smaller batches are easier than those in the larger ones. In addition, it helps to get the user feedback faster and have the result in a shorter time.
Hence, the difference between the continuous delivery and continuous deployment releases of code changes is of automation. Continuous deployment release, unlike, continuous delivery are done using automation.
Benefits of CI/CD
The integration and deployment of new code change into the existing application through automation at a faster pace not only makes the life of developers easier but also makes them more efficient. Some clear advantages to using this approach include:
Shorter periods: Back to back continuous releases using CD are less time consuming and easier.
Real time visibility: End user involvement and their real time feedback during CD increases the visibility of development process in real time.
Faster software builds for issue detection and quicker resolutions: The easy integration of new code changes through CI and deployment using CD helps to release the changes earlier than compared to those done without automation.
Code quality improvement: CI/ CD allows to reduce the human interventions that leads to conflicts. CI/CD automation helps to integrate new changes into common repository. Integration at common repository helps to build up multiple times a day through proper coordination between the developers and reduce integration costs. It helps to address the issues on real time leading to easier and on time resolution.
In general, CI/CD automation not only makes the developers more responsive but also minimises the cost of the software adding more room for further development.
The quick turn around and real-world adaptability enablement offered by CI/CD tools make them mandatory for any product-based technology company. Organisations that do not adapt to this hyper reactive development and deployment cycle are under real threat of being left behind.