Holiday Checker Lambda Functions

This project is designed for educational purposes to demonstrate AWS Lambda integration with the holidays Python library. It includes two Lambda functions created for a course where lambda_function_regular.py shows a simple initial version demonstrating the holidays library usage, and lambda_function_bedrock.py is designed for AWS Bedrock Agent integration.

Project Structure

repository/
├── test/                         # Test events for AWS Lambda console
│   ├── lambda_function_bedrock/  # Test events for Bedrock function
│   └── lambda_function_regular/  # Test events for regular function
├── lambda_function_bedrock.py    # Lambda for AWS Bedrock Agent integration
├── lambda_function_regular.py    # Standalone Lambda for testing/demo
├── requirements.txt              # Python dependencies
└── Dockerfile                    # Docker configuration for layer creation

Lambda Functions

Both functions check if a specific date is a holiday in a given country, but serve different educational purposes:

• lambda_function_regular.py: Simple version demonstrating basic holidays library usage
• lambda_function_bedrock.py: Advanced version for AWS Bedrock Agent integration

Prerequisites

• Python 3.9+
• holidays library

Setup Instructions

1. Create Lambda Layer

Option 1: Using Virtual Environment

Create Virtual Environment

virtualenv venv

# Or specify Python version:
virtualenv -p python3.13 venv

Activate Virtual Environment

• macOS/Linux:

  source venv/bin/activate

• Windows:

  venv\Scripts\activate

# Install dependencies to layer directory
pip install -r requirements.txt -t python/

# Create layer ZIP file
zip -r aws-lambda-layer.zip python/

Option 2: Using Docker

1. Prepare the Layer Package:
   • If you prefer to skip this step, use the pre-built python_dependencies.zip file provided in the tutorial directory. This file contains all required dependencies and can be uploaded directly as a layer.
   • If you want to build your own layer:
     • Detailed instructions are available in the Managing Dependencies in AWS Lambda with Docker-Generated Layers tutorial.
     • Ensure you have the requirements.txt and Dockerfile files provided in the tutorial directory.
     • Execute the following commands on your local machine to build a .zip file for your Lambda Layer:
       • Build the Docker Image:

         docker build -t lambda_layer .

       • Run a Container:

         docker run --name my_lambda_layer_container lambda_layer

       • Export the Layer:

         docker cp my_lambda_layer_container:/home/python_dependencies.zip .

       • Cleanup (Optional):

         docker stop my_lambda_layer_container
         docker rm my_lambda_layer_container
         docker rmi lambda_layer

Upload Layer to AWS

# Upload layer via AWS CLI
aws lambda publish-layer-version \
    --layer-name holiday-checker-layer \
    --zip-file fileb://aws-lambda-layer.zip \
    --compatible-runtimes python3.9 python3.10 python3.11 python3.12

2. Configure Lambda Function

• Runtime: Python 3.9+
• Handler: lambda_function.lambda_handler
• Layer: Add the layer created above

3. Configure Lambda Permissions for Bedrock

Note: AWS Bedrock requires Lambda resource-based policies to invoke the function.

• Navigate to the Configuration tab.
• In the left-hand menu, select Permissions.
• Under the Resource-based policy statements section, click Add permissions.
• In the dialog, go to AWS account tab and configure the following:
  • Statement ID: AllowBedrockInvoke
  • Principal: bedrock.amazonaws.com
  • Action: lambda:InvokeFunction
• Click Save to apply the policy.
• The new policy should appear in the Resource-based policy statements section. Ensure it matches the following structure:

  {
      "Version": "2012-10-17",
      "Id": "default",
      "Statement": [
         {
            "Sid": "AllowBedrockInvoke",
            "Effect": "Allow",
            "Principal": {
            "Service": "bedrock.amazonaws.com"
            },
            "Action": "lambda:InvokeFunction",
            "Resource": "arn:aws:lambda:<region>:<account-id>:function:<function-name>"
         }
      ]
   }

Testing

JSON test files for AWS Lambda console testing are available in the test/ directory. These files contain various test scenarios that can be used to validate the Lambda functions.

References

• holidays Python Library
• AWS Lambda Layers
• AWS Bedrock Agent Action Groups
• AWS Bedrock Lambda Integration