As a seasoned professional with over a decade of experience in agile working, I understand the importance of a comprehensive grasp of the tools and practices that govern software lifecycles. A crucial part of this is Continuous Integration and Continuous Deployment (CI/CD), which is often overlooked by those in Scrum roles. This article will delve into CI/CD, from development and version control to deployment in modern cloud environments.

Why CI/CD Matters for Scrum Masters

Continuous integration(CI) involves regularly merging code changes into a central repository, followed by automated testing. Continuous deployment(CD) further automates the process, releasing code to production once it has passed all tests.

Scrum Masters may not directly handle CI/CD pipelines, but understanding this process can greatly benefit the team:

1. Improved Communication: Knowing CI/CD allows Scrum Masters to communicate more effectively with their development teams, especially when discussing deployment schedules, bug handling, and pipeline failures.
2. Efficiency in Planning: Understanding the time and resources required for integration and deployment can aid Scrum Masters in facilitating more effective Sprint planning.
3. Risk Management: CI/CD practices enable rapid feedback on code changes, allowing teams to identify and address issues quickly. This can help Scrum Masters better manage project risks.
4. Quality Assurance: Automated tests in CI/CD pipelines help maintain code quality. Understanding this can enable Scrum Masters to stress the importance of testing and quality in their teams.

Starting With Development and Version Control: GitHub

Before we discuss CI/CD, let’s touch on the critical first step in the development cycle: writing code and managing versions. A tool like GitHub, a widely-used Git repository hosting service, is where most developers will start their work. It’s a platform for version control and collaboration, allowing developers to work on projects without stepping on each other’s toes.

Key GitHub concepts for Scrum Masters:

• Repository (Repo): This is where all project files for a particular project live. It can be thought of as a project directory.
• Branch: A branch is a parallel version of a repository. It is a copy of the main branch within the repository. Still, it does not affect the primary or main branch allowing developers to work freely without disrupting the live production code.
• Pull Request (PR): When someone completes their task or feature, they commit their code and open a pull request. This lets the team review the code before it’s merged into the main branch.

Building the Bridge to Deployment: Jenkins and GitLab CI/CD

Once code is written, tested, and merged into the main branch via GitHub, it’s time to integrate and deploy — this is where CI/CD comes in. Jenkins and GitLab CI/CD are common tools used in this space.

Testing in Jenkins

Testing is a fundamental part of Continuous Integration. In Jenkins, this process can be automated by defining specific steps in the Jenkins pipeline. Here are a few types of tests that are typically run:

• Unit Tests are the most basic tests, checking individual functions or methods. They are usually written and maintained by the developers working on the code.
• Integration Tests: These tests check if different pieces of the modules are working together as expected.
• Functional Tests: Also known as End-to-End tests, these tests check the application’s functionality by testing it in ways a user might interact with it.
• Performance Tests: These tests verify the responsiveness, reliability, scalability, and stability of a system under a certain workload.

Jenkins can run these tests automatically every time new code is pushed to the repository or at specified times and report the results. If a test fails, the team can be alerted to address the issue immediately.

Building Artifacts in Jenkins

Once the code has passed all tests, Jenkins can “build” the software. This involves compiling the code, transforming it from source code into a format that a computer can execute. The output of this build process is called an “artifact.”

Artifacts are stored in the Jenkins server or can be configured to keep in an artifact repository like Nexus or Artifactory. They are versioned and include everything needed to run the software — a .jar file for a Java application, a .exe for a Windows application, or a .deb or .rpm for a Linux application. Artifacts can also be Docker images, which can be run as containers.

Artifacts are the final product of the CI process and are what gets deployed in the CD process. By versioning artifacts and storing them in a repository, teams can always know what version of the software is running in each environment. They can easily roll back to a previous version if a problem arises.

Jenkins and GitLab CI/CD

Jenkins, an open-source automation server, is a popular choice for implementing CI/CD pipelines. It offers numerous plugins, making it adaptable to different projects and workflows.

GitLab, a web-based DevOps lifecycle tool, provides an integrated CI/CD platform. It’s seamless Integration with GitLab’s version control and other features.

Deploying to the Cloud or Data Centers: Docker and Kubernetes

The final piece of the development is the deployment of the application. Today, two tools are instrumental in this process: Docker and Kubernetes. Docker will allow us to package an application with its dependencies into a standardized unit called a container for development. Kubernetes is a modern container orchestration platform for automating these containerized applications’ deployment, scaling, and management.

Key Docker and Kubernetes concepts for Scrum Masters:

• Docker:
• Container: A lightweight, stand-alone, executable package that includes everything needed to run the software, including the code, a runtime, libraries, environment variables, and config files.
• Image: A lightweight, stand-alone, executable package with everything needed to run the software. Docker images become containers when they run on Docker Engine.
• Dockerfile: A text document that contains all the commands a user needs to call on the command line to assemble an image.
• Kubernetes:
• Pod: The smallest and simplest unit in Kubernetes. Pod represents a running process on your cluster and can contain one or multiple containers.
• Service: Service is a way to expose the application running on Pods as a network service.
• Deployment: Provide updates for Pods and Replicas. You will describe the desired state in a Deployment. Deployment Controller will take the desired state and change the actual state in a controlled manner.
• Ingress: An API object that manages access to services from outside a cluster, typically HTTP.

Conclusion

In the rapidly evolving landscape of software development, it is pivotal for Scrum Masters to maintain a broad understanding of the tools and practices used throughout the software lifecycle. While not directly responsible for the implementation or management of CI/CD pipelines, version control, or container orchestration, a solid grounding in these areas can prove invaluable.

This understanding allows Scrum Masters to communicate more effectively with the development and operations teams, fostering a collaborative environment where everyone understands the challenges and processes of delivering high-quality software. It can help to streamline planning, manage project risks, and uphold quality standards.

Moreover, it can empower Scrum Masters to better advocate for their teams by highlighting potential bottlenecks or areas for improvement in the development and deployment pipeline and facilitating discussions on how to address them.

In Scrum, shared understanding, continuous improvement, and effective communication are key to success. By expanding their knowledge beyond the Scrum framework, Scrum Masters can significantly enhance their efficacy in these areas, driving their teams toward more successful project outcomes.