• What is DevOps?
• CI/CD Pipeline
• Continuous testing goes beyond test automation
• The CD pipeline automates changes to multiple environments
• CI/CD enables more frequent code deployments

What is DevOps?

The DevOps is the combination of two words, one is Development and other is Operations. It is a culture to promote the development and operation process collectively. DevOps tools such as Git, Ansible, Docker, Puppet, Jenkins, Chef, Nagios, and Kubernetes are popular tools in market. DevOps allows a single team to handle the entire application lifecycle, from development to testing, deployment, and operations. DevOps helps you to reduce the disconnection between software developers, quality engineers (qe), and system administrators.

DevOps has become one of the most valuable business disciplines for enterprises or organizations. With the help of DevOps, quality, and speed of the application delivery has improved to a great extent. DevOps is nothing but a practice or methodology of making “Developers” and “Operations” folks work together. DevOps represents a change in the IT culture with a complete focus on rapid IT service delivery through the adoption of agile practices in the context of a system-oriented approach.

CI/CD Pipeline

What is CI/CD? Continuous integration and continuous delivery Continuous integration (CI) and continuous delivery (CD) embody a culture, set of operating principles, and collection of practices that enable application development teams to deliver code changes more frequently and reliably. The implementation is also known as the CI/CD pipeline. CI/CD is one of the best practices for devops teams to implement. It is also an agile methodology best practice, as it enables software development teams to focus on meeting business requirements, code quality, and security because deployment steps are automated. Continuous integration is a coding philosophy and set of practices that drive development teams to implement small changes and check in code to version control repositories frequently. Because most modern applications require developing code in different platforms and tools, the team needs a mechanism to integrate and validate its changes.

The technical goal of CI is to establish a consistent and automated way to build, package, and test applications. With consistency in the integration process in place, teams are more likely to commit code changes more frequently, which leads to better collaboration and software quality.

Continuous delivery(CD) picks up where continuous integration ends. CD automates the delivery of applications to selected infrastructure environments. Most teams work with multiple environments other than the production, such as development and testing environments, and CD ensures there is an automated way to push code changes to them. CI/CD tools help store the environment-specific parameters that must be packaged with each delivery. CI/CD automation then performs any necessary service calls to web servers, databases, and other services that may need to be restarted or follow other procedures when applications are deployed.

Continuous integration and continuous delivery require continuous testing because the objective is to deliver quality applications and code to users. Continuous testing is often implemented as a set of automated regression, performance, and other tests that are executed in the CI/CD pipeline. A mature CI/CD DevOps practice has the option of implementing continuous deployment where application changes run through the CI/CD pipeline and passing builds are deployed directly to production environments. Teams practicing continuous delivery elect to deploy to production on a daily or even hourly schedule, though continuous delivery isn’t always optimal for every business application. 

Continuous testing goes beyond test automation

Automated testing frameworks help quality assurance engineers define, execute, and automate various types of tests that can help development teams know whether a software build passes or fails. They include functionality tests that are developed at the end of every sprint and aggregated into a regression test for the entire application. These regression tests then inform the team whether a code change failed one or more of the tests developed across all functional areas of the application where there is test coverage. A best practice is to enable and require developers to run all or a subset of regressions tests in their local environments. This step ensures that developers only commit code to version control after regression tests pass on the code changes.

Regression tests are just the start. Performance testing, API testing, static code analysis, security testing, and other testing forms can also be automated. The key is to be able to trigger these tests either through command line, webhook, or web service and that they respond with success or fail status codes. Once testing is automated, continuous testing implies that the automation is integrated into the CI/CD pipeline. Some unit and functionality tests can be integrated into CI that flags issues before or during the integration process. Tests that require a full delivery environment such as performance and security testing are often integrated into CD and performed after builds are delivered to target environments.

The CD pipeline automates changes to multiple environments

Continuous delivery is the automation that pushes applications to delivery environments. Most development teams typically have one or more development and testing environments where application changes are staged for testing and review. A CI/CD tool such as Jenkins, CircleCI, AWS CodeBuild, Azure DevOps, Atlassian Bamboo, or Travis CI is used to automate the steps and provide reporting. A typical CD pipeline has build, test, and deploy stages. More sophisticated pipelines include many of these steps:

• Pulling code from version control and executing a build.
• Executing any required infrastructure steps that are automated as code to stand up or tear down cloud infrastructure.
• Moving code to the target computing environment.
• Managing the environment variables and configuring them for the target environment.
• Pushing application components to their appropriate services, such as web servers, API services, and database services.
• Executing any steps required to restarts services or call service endpoints that are needed for new code pushes.
• Executing continuous tests and rollback environments if tests fail.
• Providing log data and alerts on the state of the delivery.

As an example, Jenkins users define their pipelines in a Jenkinsfile that describes different stages such as build, test, and deploy. Environment variables, options, secret keys, certifications, and other parameters are declared in the file and then referenced in stages. The post section handles error conditions and notifications. More sophisticated CD may have other steps such as performing data synchronizations, archiving information resources, or performing application and library patching. CI/CD tools typically support a marketplace of plug-ins. For example, Jenkins lists more than 1,500 plug-ins that support integration with third-party platforms, user interface, administration, source code management, and build management. Once a CI/CD tool is selected, development teams must make sure that all environment variables are configured outside the application. CI/CD tools allow setting these variables, masking variables such as passwords and account keys, and configuring them at time of deployment for the target environment.

CD tools also provide dashboard and reporting functions. If builds or deliveries fail, they alert developers with information on the failures. They integrate with version control and agile tools, so they can be used to look up what code changes and user stories made up a build.

CI/CD enables more frequent code deployments

To recap, CI packages and tests software builds and alerts developers if their changes failed any unit tests. CD is the automation that delivers changes to infrastructure and executes additional tests. 

CI/CD pipelines are designed for businesses that want to improve applications frequently and require a reliable delivery process. The added effort to standardize builds, develop tests, and automate deployments is the manufacturing process for deploying code changes. Once in place, it enables teams to focus on the process of enhancing applications and less on the system details of delivering it to computing environments.

CI/CD is a DevOps best practice because it addresses the misalignment between developers who want to push changes frequently, with operations that want stable applications. With automation in place, developers can push changes more frequently. Operations teams see greater stability because environments have standard configurations, there is continuous testing in the delivery process, environment variables are separated from the application, and rollback procedures are automated.

The impact of implementing CI/CD pipelines can be measured as a DevOps key performance indicator (KPI). KPI’s such as deployment frequency, change lead time, and mean time to recovery (MTTR) from an incident are often improved when CI/CD with continuous testing is implemented. However, CI/CD is just one process that can drive these improvements, and there are other prerequisites to improving deployment frequencies.

Getting started with CI/CD requires development teams and operational teams to collaborate on technologies, practices, and priorities. Teams need to develop consensus on the right approaches for their business and technologies so that once CI/CD is in place the team is onboard with following practices consistently.

I hope you found these tips helpful! Thank you for reading.

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