CodePipeline for Deployments

Welcome! In modern software development, automating releases is key. AWS CodePipeline helps you achieve Continuous Integration and Continuous Delivery (CI/CD) for your applications, including serverless ones.

CodePipeline is a fully managed service that automates your release process. It orchestrates the steps needed to get your code changes from a source repository through various stages and into production.

Automating your deployments with CodePipeline offers several benefits:

• Faster Releases: Deliver new features and bug fixes to users quicker.
• Improved Reliability: Standardized, automated processes reduce human error.
• Consistent Deployments: Ensures every change follows the same path and checks.
• Visibility: Track the status of your releases in real-time.

It acts as the central orchestrator for your serverless CI/CD.

A CodePipeline typically consists of several stages, each with one or more actions. The most common stages are:

• Source: Where your code originates (e.g., CodeCommit, GitHub).
• Build: Where your code is compiled, tested, and packaged (e.g., CodeBuild).
• Deploy: Where your application is deployed to AWS resources (e.g., CloudFormation, SAM).
• Test: Where automated tests run to validate the deployed application.

These stages execute in a defined order, creating a workflow.

The Source stage is the starting point of your pipeline. When you push new code to your repository, CodePipeline detects the change and automatically starts the pipeline.

Common source providers include AWS CodeCommit, GitHub, GitLab, and Amazon S3. For serverless applications, your source typically contains your Lambda code and serverless template (like a SAM template).

After the source code is retrieved, it moves to the Build stage. Here, AWS CodeBuild takes over. CodeBuild compiles your code, runs unit tests, and packages your serverless application artifacts.

For a serverless application, this often means creating a deployment package (a .zip file for Lambda) and preparing your AWS Serverless Application Model (SAM) template for deployment.

CodeBuild uses a buildspec.yml file in your source repository to define the build commands. Here's a common structure for a Python Lambda with SAM:

The Deploy stage takes the artifacts produced by the build stage and deploys them to your AWS account. For serverless applications, this typically involves AWS CloudFormation, often orchestrated by AWS SAM.

CodePipeline can directly integrate with CloudFormation to execute a SAM template. It uses Change Sets to preview and safely apply infrastructure updates, minimizing risks.

In CodePipeline, a deploy action for a SAM application might look like this (conceptually, configured in the pipeline definition):

• Action Provider: CloudFormation
• Action Mode: REPLACE_ON_FAILURE or CREATE_UPDATE
• Stack Name: YourServerlessAppStack
• Template Path: The path to your SAM template (e.g., build-artifact::template.yaml)
• Capabilities: CAPABILITY_IAM (required for many serverless deployments)

This tells CodePipeline to update your CloudFormation stack based on the provided template.

While unit tests run in the Build stage, a dedicated Test stage in CodePipeline allows for broader validation after deployment. This could include:

• Integration tests against the deployed API.
• Smoke tests to ensure basic functionality.
• End-to-end tests for critical user flows.

You can use another CodeBuild project or a Lambda function to execute these tests. If tests fail, the pipeline can stop the deployment.

Consider a serverless application deployed with AWS CodePipeline. Which of the following AWS services are commonly integrated into CodePipeline's stages for a typical serverless CI/CD workflow?

You've learned how AWS CodePipeline orchestrates your serverless application deployments. Key takeaways:

• CodePipeline automates CI/CD from code commit to deployment.
• It uses stages like Source, Build, and Deploy.
• CodeCommit provides the source, CodeBuild performs builds (using buildspec.yml), and CloudFormation/SAM handles deployments.
• Test stages ensure quality before production.

By leveraging CodePipeline, you create robust and repeatable deployment processes for your serverless applications!