3.1.1 Dependencies & Packaging

Lambda Deployment Packaging

Lambda Deployment Package Types

Lambda supports 2 types of deployment packages:

1. Container images - Up to 10GB
2. ZIP file archives - Up to 250MB unzipped

Packaging Methods

Lambda Layers

Question thi: Function > 100MB exceeds deployment package size limits. Cần refactor để pull additional code và dependencies từ different source. Dùng gì?

Answer: Lambda Layers

Lambda Layers là distribution mechanism cho:

• Libraries
• Custom runtimes
• Other function dependencies

Lợi ích:

• ✅ Manage function code independently from unchanging code/resources
• ✅ Configure function to use layers you create, AWS provides, hoặc from other customers
• ✅ Include layers to use libraries without including them in deployment package
• ✅ Reduce deployment package size

Layer structure:
python/
└── lib/
    └── python3.12/
        └── site-packages/
            ├── requests/
            └── pandas/

Properties:

• Share dependencies across multiple functions
• Versioned, immutable
• Max 5 layers per function
• Total unzipped size (function + layers) ≤ 250MB

Layers vs Container Images

Question: Dùng layers với container images?

Answer: NO

Với container images, bạn package preferred runtime, libraries, và dependencies into container image khi build image.

ZIP Package Structure

my-function.zip
├── lambda_function.py      # Handler
├── requirements/            # Dependencies
│   ├── boto3/
│   └── requests/
└── utils/                   # Custom modules
    └── helpers.py

# Package Python Lambda
pip install -r requirements.txt -t ./package
cp lambda_function.py ./package/
cd package && zip -r ../function.zip .

Managing Dependencies

Lambda Execution Environment

• Lambda includes libraries in execution environment
• Có thể use built-in libraries

Update Lambda with Additional Dependencies

Node.js example:

• Nếu function depends on libraries khác AWS SDK for JavaScript
• Use NPM to include them trong deployment package
• Nếu libraries use native code → use Amazon Linux environment to create package

Add newer SDK version:

• Có thể add SDK to deployment package nếu cần newer version
• Hoặc ensure version doesn’t change trong future

Native Libraries

Nếu deployment package contains native libraries:

# Build with SAM
sam build --use-container

• --use-container builds package inside Docker image
• Docker image compatible với Lambda execution environment

CDK Dependencies

Dependencies cho AWS CDK application/library managed bằng:

• pip (Python)
• npm (Node.js)
• yarn (Node.js)
• Maven (Java)
• NuGet (.NET)

Container Image

FROM public.ecr.aws/lambda/python:3.12
COPY requirements.txt .
RUN pip install -r requirements.txt
COPY app.py .
CMD ["app.handler"]

• Push to ECR → Lambda references ECR image
• Dùng AWS base images hoặc custom (implement Runtime API)
• Package runtime, libraries, dependencies into image

Deployment Package Size Scenarios

Scenario 1: Function > 100MB

• Solution: Use Lambda Layers
• Extract libraries to layers
• Reduce deployment package size

Scenario 2: Function with native libraries

• Solution: sam build --use-container
• Build trong Docker compatible với Lambda environment

Scenario 3: Complex dependencies, Docker workflow

• Solution: Container image (up to 10GB)
• Package everything into image