What is CI/CD?
Automate the software development workflows and deploy better quality code, more often. Using a continuous and iterative process to build, test, and deploy helps avoid bugs and code failures.
CI/CD explained
CI/CD :Continuous integration and continuous delivery/deployment.
CI/CD automates much or all of the manual human intervention traditionally needed to get new code from a commit into production, encompassing the build, test (including integration tests, unit tests, and regression tests), and deploy phases, as well as infrastructure provisioning.
With a CI/CD pipeline, development teams can make changes to code that are then automatically tested and pushed out for delivery and deployment.
As a result code releases happen faster.
It decreases tedious and time-consuming manual development work and legacy approval processes, freeing DevOps teams to be more innovative in their software development.
Automation makes processes predictable and repeatable so that there is less opportunity for error from human intervention.
Continuous integration (CI):
Continuous integration means integrating all your code changes into the main branch of a shared source code repository .
It automatically tests each change when you commit or merge them, and automatically kicking off a build.
With continuous integration, errors and security issues can be identified and fixed more easily.
By merging changes frequently and triggering automatic testing and validation processes, it minimize the possibility of code conflict, even with multiple developers working on the same application.
A secondary advantage is that you don't have to wait long for answers and can, if necessary, fix bugs and security issues while the topic is still fresh in your mind.
Continuous delivery (CD):
Once code has been tested and built as part of the CI process, CD takes over during the final stages to ensure it's packaged with everything it needs to deploy to any environment at any time.
With CD, the software is built so that it can be deployed to production at any time. Then anyone can trigger the deployments manually or move to continuous deployment, where deployments are automated as well.
Continuous deployment:
Continuous deployment enables organizations to deploy their applications automatically, eliminating the need for human intervention.
With continuous deployment, DevOps teams set the criteria for code releases ahead of time and when those criteria are met and validated, the code is deployed into the production environment. This allows organizations to be more nimble and get new features into the hands of users faster.
Continuous Testing:
Continuous testing is a software testing practice where tests are continuously run in order to identify bugs as soon as they are introduced into the codebase.
In a CI/CD pipeline, continuous testing is typically performed automatically, with each code change triggering a series of tests to ensure that the application is still working as expected. This can help to identify problems early in the development process and prevent them from becoming more difficult and costly to fix later on.
Continuous testing can also provide valuable feedback to developers about the quality of their code, helping them to identify and address potential issues before they are released to production.
In continuous testing, various types of tests are performed within the CI/CD pipeline. These can include:
Unit testing, which checks that individual units of code work as expected
Integration testing, which verifies how different modules or services within an application work together
Regression testing, which is performed after a bug is fixed to ensure that specific bug won't occur again
CI/CD fundamentals
There are eight fundamental elements of CI/CD that help ensure maximum efficiency for your development lifecycle.
A single source repository
Source code management (SCM) that houses all necessary files and scripts to create builds is critical. The repository should contain everything needed for the build. This includes source code, database structure, libraries, properties files, and version control. It should also contain test scripts and scripts to build applications.Frequent check-ins to main branch
Integrate code in your trunk, mainline or master branch — i.e., trunk-based development — early and often. Avoid sub-branches and work with the main branch only. Use small segments of code and merge them into the branch as frequently as possible. Don't merge more than one change at a time.Automated builds
Scripts should include everything you need to build from a single command. This includes web server files, database scripts, and application software. The CI processes should automatically package and compile the code into a usable application.Self-testing builds
CI/CD requires continuous testing. Testing scripts should ensure that the failure of a test results in a failed build. Use static pre-build testing scripts to check code for integrity, quality, and security compliance. Only allow code that passes static tests into the build.Frequent iterations
Multiple commits to the repository results in fewer places for conflicts to hide. Make small, frequent iterations rather than major changes. By doing this, it's possible to roll changes back easily if there's a problem or conflict.Stable testing environments
Code should be tested in a cloned version of the production environment. You can't test new code in the live production version. Create a cloned environment that's as close as possible to the real environment. Use rigorous testing scripts to detect and identify bugs that slipped through the initial pre-build testing process.Maximum visibility
Every developer should be able to access the latest executables and see any changes made to the repository. Information in the repository should be visible to all. Use version control to manage handoffs so developers know which is the latest version. Maximum visibility means everyone can monitor progress and identify potential concerns.Predictable deployments anytime
Deployments should be so routine and low-risk that the team is comfortable doing them anytime. CI/CD testing and verification processes should be rigorous and reliable, giving the team confidence to deploy updates at any time. Frequent deployments incorporating limited changes also pose lower risks and can be easily rolled back.
What is CI/CD?
CI or Continuous Integration is the practice of automating the integration of code changes from multiple developers into a single codebase. It is a software development practice where the developers commit their work frequently into the central code repository (Github or Stash). Then there are automated tools that build the newly committed code and do a code review, etc as required upon integration. The key goals of Continuous Integration are to find and address bugs quicker, make the process of integrating code across a team of developers easier, improve software quality and reduce the time it takes to release new feature updates.
CD or Continuous Delivery is carried out after Continuous Integration to make sure that we can release new changes to our customers quickly in an error-free way. This includes running integration and regression tests in the staging area (similar to the production environment) so that the final release is not broken in production. It ensures to automate the release process so that we have a release-ready product at all times and we can deploy our application at any point in time.
What Is a Build Job?
A Jenkins build job contains the configuration for automating a specific task or step in the application building process. These tasks include gathering dependencies, compiling, archiving, or transforming code, and testing and deploying code in different environments.
Jenkins supports several types of build jobs, such as freestyle projects, pipelines, multi-configuration projects, folders, multibranch pipelines, and organization folders.
What is Freestyle Projects ?? 🤔
A freestyle project in Jenkins is a type of project that allows you to build, test, and deploy software using a variety of different options and configurations. Here are a few tasks that you could complete when working with a freestyle project in Jenkins: