Azure DevOps Pipelines expose a few capabilities intended to make automation more dynamic, reusable, and flexible. These include conditional execution, loops, matrix strategies, dependencies, and template reuse to create flexible pipelines that can be catered to different scenarios. Such capabilities allow teams to shape pipelines according to different environments, application types, and deployment strategies.
This blog will analyse how to create flexible Azure DevOps pipelines with condition checks, matrix jobs, dependencies, and template parameterization through live, real-life examples.
1. Conditional Execution with `condition`
What is Conditional Execution?
The Azure DevOps conditional execution of pipeline stages, jobs, and steps allows you to determine their execution. The expression for running the step is evaluated during the execution of the `condition` property.
# Example 1: Run a Stage Only on the Main Branch
This will make the Deploy stage run only when the pipeline is run on the `main` branch.
# Example 2: Run a Job Only If a Previous Job Succeeds
Here, the Test job runs only if the Build job is successful.
# Example 3: Skip Deployment If a Build Fails
This skipped deployment on failure. Declares a more stable build.
2. Looping `each` When You Do Something Again & Again
What is Looping in Azure Pipelines?
Looping allows an action to be repeated multiple times for multiple inputs, thus bringing down the number of lines in the pipeline and giving it more efficiency.
# Example 1: Looping Through Multiple Environments
This dynamically creates Deploy_Dev, Deploy_Test, and Deploy_Prod.
# Example 2: Looping for a List of Services
This allows a service-specific deployment action.
3. Matrices for Parallel Execution
What Is Matrix Strategy?
This strategy is the one through which one job can be executed in parallel with various other configurations.
The maxParallel optional keyword defines the maximum number of matrix legs to execute simultaneously at one time. No limit is enforced if maxParallel is omitted or is set to 0.
# Example 1: Run Tests on Different OS Versions
This runs the Test job in parallel on Linux, Windows, and Mac, speeding up the tests.
# Example 2: Build With Different Node Versions
This builds in parallel with different versions of Node.js.
4. Job & Stage Dependency Handling
Managing Execution Flow: Execution order can be defined between jobs or stages using `dependsOn.`
# Example 1: Deploy to Production only when Staging Succeeds
This guarantees that Production is done only when Staging succeeds.
5. Parameterization for Templates to Make Them Reusable
What Are Templates?
Templates are for defining reusable pipeline configurations that take parameters.
# Example 1: A Parameterized Build Template.
Layered Deployment with Optional Execution based on input parameters passed during runtime execution.
This allows for selective layer deployment which can be used to provision only required infrastructure rather than disrupting the full infrastructure.
Conclusion
Azure DevOps offers several flexibility options, including if conditions, loops, matrix strategies, dependencies, and templates, to carry out dynamic pipeline execution. Through the use of these methods, teams are able to make their pipelines more scalable, efficient, and reusable with less manual labor.
Begin incorporating these flexibility options in your Azure DevOps pipelines today for improved automation and workflow optimization!