Introduction: Bridging the Gap Between Code and Infrastructure

Serverless computing has revolutionized application deployment, enabling developers to focus on code without worrying about infrastructure management. AWS Lambda provides a powerful platform for running serverless applications, while GitLab CI/CD simplifies automated deployments. This guide bridges the gap between code and infrastructure, demonstrating how to deploy AWS Lambda functions seamlessly with GitLab CI/CD.

Prerequisites: Essential Tools for Seamless Deployment

Before diving into deployment, ensure you have the following tools and setups:

  • AWS Account: Active account with necessary permissions.
  • GitLab Account: Repository set up for your project.
  • AWS CLI: Installed and configured with access credentials.
  • Node.js and NPM: Installed for building and packaging Lambda functions.
  • Git: Installed for version control.
  • YAML Basics: Familiarity with YAML for GitLab CI/CD pipelines.

AWS Setup: Creating Users and Setting IAM Permissions

  1. Create an IAM User:
    • Go to the AWS Management Console.
    • Navigate to IAM > Users > Add User.
    • Provide a username and select Programmatic Access.
  2. Attach Policies:
    • Attach the following policies for Lambda deployments:
      • AWSLambdaFullAccess
      • AmazonS3FullAccess (if using S3 for code storage)
      • IAMFullAccess (for role creation if needed).
  3. Save Access Keys:
    • Save the Access Key ID and Secret Access Key for later use in GitLab.

GitLab Configuration: Storing Sensitive Credentials

  1. Securely Store AWS Credentials:
    • Go to Settings > CI/CD > Variables in your GitLab repository.
    • Add the following environment variables:
      • AWS_ACCESS_KEY_ID
      • AWS_SECRET_ACCESS_KEY
      • Optional: AWS_REGION (e.g., us-east-1).
  2. Set Permissions:
    • Ensure the variables are masked and protected to prevent exposure.

Automated Deployment Pipeline: Building, Testing, and Deploying with GitLab CI/CD

  1. Define .gitlab-ci.yml:
    • Create a .gitlab-ci.yml file in your repository root with the following content:

stages:

  – build

  – deploy

build:

  stage: build

  image: node:latest

  script:

    – npm install

    – zip -r function.zip .

  artifacts:

    paths:

      – function.zip

deploy:

  stage: deploy

  image: amazon/aws-cli:latest

  script:

    – aws lambda update-function-code –function-name myLambdaFunction –zip-file fileb://function.zip

  only:

    – main

  1. Customize the Pipeline:
    • Replace myLambdaFunction with your actual Lambda function name.
    • Add unit tests in the build stage for better reliability.

Deployment Verification: Locating Your Lambda Function in AWS

  1. Check AWS Lambda Console:
    • Log in to the AWS Management Console.
    • Navigate to Lambda > Functions.
    • Verify the updated deployment timestamp and function code.
  2. Test Your Function:

Use the Test tab in the Lambda console or invoke it via the AWS CLI:
aws lambda invoke –function-name myLambdaFunction out.json

Beyond the Basics: Exploring Further Deployment Possibilities

  • Environment Variables: Use Lambda environment variables for configuration.
  • Infrastructure as Code: Automate Lambda creation with AWS CloudFormation or Terraform.
  • Event Triggers: Explore Lambda event sources like S3, DynamoDB, or API Gateway.
  • Monitoring and Alerts: Use AWS CloudWatch to monitor Lambda performance.

References

Building a CI/CD pipeline for cross-account deployment of an AWS Lambda API with the Serverless Framework

Using GitLab CI/CD to deploy with AWS SAM