DevOps is a software development methodology that integrates software development (Dev) with system operations (Ops). The system delivers new software features, updates, and fixes that align with business goals.
DevOps methodology also covers:
Designing new features based on goals, usage patterns, and customer feedback.
Fixing, recovering, and hardening the system when issues occur.
One component of DevOps methodology is the continuous integration (CI) and continuous delivery (CD) pipeline. A CI/CD pipeline moves information, code, and resources from a source control commit through a series of steps to produce the system. Steps include build, test, and release.
You can use Azure DevTest Labs in CI/CD pipelines. This article discusses using DevTest Labs in CI/CD build and release pipelines in an enterprise environment.
Benefits of DevTest Labs in DevOps workflows
A lab should focus on a team that's working in a feature area. This common focus allows faster changes, while limiting any negative effects to a smaller group. Changes or problems happen in the lab environment, without affecting anything else.
The common focus allows for sharing area-specific resources, like tools, scripts, and Azure Resource Manager (ARM) templates. Developers can use shared resources to create virtual machines (VMs) with all the code, tools, and configuration they need. ARM templates create lab VMs and lab environments with the appropriate Azure resources. The templates create resources dynamically, or by creating base images with customizations.
For example, consider a scenario where the product is a standalone system that installs on a customer's machine. DevTest Labs can create lab VMs that have customer software, artifacts, and configurations installed, for quick inner loop code testing.
Here are some benefits of using labs in DevOps workflows:
Focused access: Using a lab as a component associates a specific ecosystem with limited people. Usually, a team or group working in a common area or a specific feature has a lab assigned to them.
Infrastructure replication in the cloud: A developer can quickly set up a development ecosystem that includes a developer VM with source code and tools. A developer can also create an environment that's nearly identical to the production configuration, for faster inner loop development.
Pre-production environments: A lab in the CI/CD pipeline can run several different pre-production environments or machines at the same time, for asynchronous testing. You can deploy and manage different support infrastructures and build agents in a lab.
Use labs in CI/CD pipelines
The CI/CD pipeline is a critical DevOps component. The pipeline integrates the code from a developer's pull request with existing code, and deploys the code to the production ecosystem. For DevTest Labs integration, not all resources need to be in a lab. For example, you could set up a Jenkins host outside the lab for a more persistent resource. Here are some specific examples of integrating labs into the CI/CD pipeline.
Build
The build pipeline creates a package of components to test together and hand off to release. Dynamically building infrastructure allows for greater control. Labs can be part of the build pipeline as locations for build agents and other support resources. DevTest Labs can restrict lab access, which increases security for build agents and reduces the possibility of accidental corruption.
With the ability to have multiple environments in a lab, each build can run asynchronously. The build ID is part of the environment information that uniquely identifies the resources in a specific build.
Test
A CI/CD pipeline can automate creating DevTest Labs resources like VMs and environments for automated and manual testing. The pipeline uses build information artifacts or formulas to create VMs with different custom test configurations.
Release
The release process can use DevTest Labs for verification before the code is deployed. The process is similar to testing. Production resources shouldn't be deployed in DevTest Labs.
Customization
Azure Pipelines, a component of Azure DevOps Services, has existing tasks to manipulate VMs and environments within specific labs. Azure Pipelines is one way to manage the CI/CD pipeline. You can integrate a lab into any system that supports calling REST APIs, executing PowerShell scripts, or using Azure CLI.
Some CI/CD pipeline managers have existing open-source plugins that can manage Azure and DevTest Labs resources. You might need to use custom scripting to fit the needs of the pipeline. When executing a task, use a service principal with the appropriate role, usually Contributor, to access the lab.
Create automated pipelines that continuously build, test, and deploy your applications and prepare for Exam AZ-400: Designing and Implementing Microsoft DevOps Solutions.
This certification measures your ability to accomplish the following technical tasks: Design and implement processes and communications, design and implement a source control strategy, design and implement build and release pipelines, develop a security and compliance plan, and implement an instrumentation strategy.