Sharing the Goods: Implementing Artifact Sharing in AWS CodePipeline

Continuous integration and continuous delivery (CI/CD) pipelines often involve multiple stages, each performing specific tasks. Efficiently sharing artifacts (files or folders) between these stages optimizes the pipeline and avoids redundant processing. This article explores packaging build artifacts into a zip file and configuring AWS CodePipeline to pass them between stages for streamlined execution.

1. Packaging the Goods: Creating a Build Artifact

The process of creating a build artifact depends on your build tool and project structure. Here's a general approach:

• Identify Build Outputs: Determine the essential files or folders generated during your build process. These could be compiled code, test reports, or configuration files.

Using CodeBuild:

If you're using AWS CodeBuild for building, your buildspec.yml file defines the build steps. CodeBuild automatically captures the outputs of these steps as the build artifact.

Custom Build Environments:

For custom build environments, you'll need to implement logic to package the desired outputs into a single archive. Common tools include:

• Unix-based systems: Utilize zip or tar commands within your build script to create a compressed archive.
• Windows: Tools like 7z or PowerShell compression cmdlets can achieve the same goal.

Naming Conventions:

Maintain consistent naming conventions for your build artifacts. This aids in identification and extraction within subsequent pipeline stages.

2. Connecting the Stages: Configuring Artifact Sharing

• Navigate to the AWS CodePipeline console and select the pipeline you want to modify.

Understanding Stages:

Your pipeline likely consists of multiple stages, each handling specific tasks in the deployment process (e.g., build, test, deploy).

Specifying Output Artifacts:

• Locate the stage that generates the build artifact (e.g., the build stage using CodeBuild).
• Within that stage configuration, navigate to the "Artifact" section.
• Click "Add output artifact" and provide a descriptive name (e.g., "build-artifacts").

Defining Artifact Location:

Here's where you specify the location of your build artifact relative to the build environment:

• Under "Base directory," enter the path containing your zipped build artifact (e.g., "${CODEBUILD_OUTPUT_DIR}").
  • CodeBuild automatically sets environment variables like CODEBUILD_OUTPUT_DIR during execution.
• Optionally, use wildcards under "Files" to include specific file patterns within the archive (e.g., "**/*").

Understanding Input Artifacts:

• Navigate to the subsequent stage where you want to utilize the build artifact.
• Within that stage configuration, navigate to the "Artifact" section.

Specifying Input Artifacts:

• Click "Add input artifact" and choose the previously created output artifact from the prior stage (e.g., "build-artifacts").

These configurations instruct CodePipeline to:

• Capture the zipped build artifact from the build stage.
• Make it available as an input for the subsequent stage.

3. Extracting and Utilizing Artifacts in Subsequent Stages

The receiving stage can now access and utilize the build artifact:

• CodeBuild: If using CodeBuild in the receiving stage, environment variables like CODEBUILD_ARTIFACTS will point to the location of the extracted artifacts. You can modify your buildspec.yml to access and utilize the extracted files within your build commands.
• Custom Build Environments: Depending on your chosen build tool, you'll need to incorporate logic to extract the received artifact and access the contained files within your build scripts.

Optional: Multiple Artifacts:

CodePipeline supports managing multiple artifacts between stages. This allows you to share various types of outputs across stages – for example, build artifacts and separate test report archives.

4. The Streamlined Pipeline: Efficient Artifact Management

With artifact sharing configured, the following workflow emerges:

1. The pipeline execution triggers the build stage.
2. The build stage generates the build artifact and packages it according to your defined location and naming conventions.
3. CodePipeline captures the build artifact and makes it available as input for the subsequent stage.
4. The receiving stage receives the artifact, extracts its contents, and utilizes the files within its build process.

This approach avoids redundant processing of build outputs, optimizes pipeline performance, and simplifies the management of artifacts within your CI/CD workflow.

Additional Considerations:

• You can configure environment variables within CodePipeline to dynamically adjust artifact paths or filenames based on pipeline execution details.
• For security-sensitive artifacts, explore CodePipeline's encryption capabilities for data at rest within the pipeline storage bucket.

By implementing artifact sharing, you create a more efficient and manageable CI/CD pipeline that leverages the outputs from each stage