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Azure Pipelines - Use pipeline variables

I’m currently migrating an existing CI/CD pipeline build in Azure DevOps from the ‘classic’ build approach to YAML templates.

In our old setup we had 2 steps:

  • A CI pipeline that builds our application, runs all tests and packages the application in a Docker container. This container is then published to Azure Container Registry.
  • A Release pipeline that is triggered once the CI pipeline completes. The CI pipeline is available as an artifact.

We use the CI pipeline ‘branchname’ together with the ‘buildid’ to find the correct image inside ACR and deploy it:

example.azurecr.io/cms-spa:$(Release.Artifacts._CMS - CI.SourceBranchName).$(Release.Artifacts._CMS - CI.BuildId)

To achieve the same thing through Azure Pipelines and YAML templates we need to first define the CI build as a Pipeline Resource which I explained in this post: https://bartwullems.blogspot.com/2021/06/azure-pipelinespipeline-resource-trigger.html.

Once the pipeline resource is set, we can also use the ‘branchname’ and ‘buildid’. This can be done through Pipeline Resource variables.

The variable names are not the same as when using the Release Pipeline. Here are the available variables:

resources.pipeline.<Alias>.projectID
resources.pipeline.<Alias>.pipelineName
resources.pipeline.<Alias>.pipelineID
resources.pipeline.<Alias>.runName
resources.pipeline.<Alias>.runID
resources.pipeline.<Alias>.runURI
resources.pipeline.<Alias>.sourceBranch
resources.pipeline.<Alias>.sourceCommit
resources.pipeline.<Alias>.sourceProvider
resources.pipeline.<Alias>.requestedFor
resources.pipeline.<Alias>.requestedForID

So to find the correct ACR image inside our YAML pipeline, we need to construct the image name like this:

example.azurecr.io/cms-spa:$(resources.pipeline.cms-ci.sourceBranch).$(resources.pipeline.cms-ci.runID)

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