AWS Lambda Layer Example using AWS CDK (Python)

This project provides an example of how to create and deploy an AWS Lambda Layer using the AWS Cloud Development Kit (CDK) in Python.

📌 Overview

AWS Lambda Layers allow you to share libraries and dependencies across multiple Lambda functions. This example demonstrates how to:

• Define a Lambda Layer using AWS CDK (Python).
• Package and deploy the layer to AWS.
• Use the layer in a Lambda function.

📂 Project Structure

aws-lambda-layer-example/
│── lambda_layer/                     # Directory for Lambda layer dependencies
│── cdk/                                # AWS CDK Infrastructure
│── requirements.txt                     # Python dependencies for CDK
│── cdk.json                             # CDK Configuration
│── README.md                            # This documentation
│── LICENSE

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🚀 Prerequisites

• AWS CDK installed globally:

  npm install -g aws-cdk

• AWS CLI configured with credentials:

  aws configure

• Python 3.8+ installed
• Node.js 16+ (for AWS CDK)
• Virtual Environment setup (optional but recommended)

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📦 Installation

Clone the repository:

git clone https://github.com/your-repo/aws-lambda-layer-example.git
cd aws-lambda-layer-example

Create a virtual environment and install dependencies:

python3 -m venv .venv
source .venv/bin/activate  # On Windows use .venv\Scripts\activate
pip install -r requirements.txt

Install AWS CDK dependencies:

cdk bootstrap

🚀 Deploying to AWS

1️⃣ Synthesize the CloudFormation template

This command generates a CloudFormation template for your AWS infrastructure.

cdk synth

2️⃣ Deploy the Lambda Layer

Deploy the stack that creates the Lambda Layer:

cdk deploy LambdaLayerStack

Once deployed, note the Layer ARN from the output.

3️⃣ Deploy the Lambda Function

Deploy the Lambda function using the Layer ARN:

cdk deploy LambdaFunctionStack --parameters LayerArn="arn:aws:lambda:region:account-id:layer:LayerName:Version"

Alternatively, modify app.py to automatically retrieve the layer ARN from LambdaLayerStack.

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🔄 Updating the Lambda Layer

If you make changes to the layer, update it with:

cdk deploy LambdaLayerStack

Then, update functions that use it:

cdk deploy LambdaFunctionStack

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📌 Testing the Lambda Function

Invoke the function from the AWS CLI:

aws lambda invoke --function-name MyLambdaFunction output.json
cat output.json

Check logs via AWS CloudWatch:

aws logs tail /aws/lambda/MyLambdaFunction --follow

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🛠️ Cleanup

To delete the deployed resources and avoid AWS charges:

cdk destroy

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📜 License

This project is licensed under the MIT License. See the LICENSE file for details.

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📞 Contact & Support

For issues or contributions:

• Open an issue or pull request in this repository.
• Visit AWS Lambda Documentation.
• Contact us at info@zerodotfive.com.