Creating a Lambda function in AWS - Try It Yourself

Creating a Lambda function

📖 Scenario: You are working on a cloud project where you need to create a simple AWS Lambda function. This function will run code in the cloud without managing servers. You will create the function step-by-step using AWS CloudFormation syntax.

🎯 Goal: Build a CloudFormation template that defines a Lambda function named MySimpleFunction with a basic Python 3.9 runtime and a handler named lambda_function.lambda_handler.

📋 What You'll Learn

Create a CloudFormation template with a Resources section

Define a Lambda function resource named MySimpleFunction

Set the runtime to python3.9

Set the handler to lambda_function.lambda_handler

Use a basic inline code snippet for the Lambda function

💡 Why This Matters

🌍 Real World

CloudFormation templates are used to automate cloud infrastructure setup, making deployments repeatable and consistent.

💼 Career

Knowing how to define Lambda functions in infrastructure as code is essential for cloud engineers and developers working with AWS.

1

Create the CloudFormation template skeleton

Create a CloudFormation template with a Resources section as an empty dictionary called Resources.

AWS

Resources = {
    
}
# Your code here

Need a hint?

Start by creating a Python dictionary named Resources with no entries yet.

2

Add the Lambda function resource

Add a resource named MySimpleFunction inside Resources with the type AWS::Lambda::Function and an empty Properties dictionary.

AWS

Resources = {
    # Add MySimpleFunction resource here
}
# Your code here

Need a hint?

Inside Resources, add a key MySimpleFunction with the correct type and empty properties.

3

Configure the Lambda function properties

Inside MySimpleFunction properties, add Runtime set to python3.9, Handler set to lambda_function.lambda_handler, and Code with ZipFile containing a simple Python function def lambda_handler(event, context):\n return 'Hello from Lambda'.

AWS

Resources = {
    "MySimpleFunction": {
        "Type": "AWS::Lambda::Function",
        "Properties": {
            # Add Runtime, Handler, and Code here
        }
    }
}
# Your code here

Need a hint?

Set the runtime, handler, and inline code for the Lambda function inside Properties.

4

Complete the CloudFormation template

Add the top-level AWSTemplateFormatVersion set to 2010-09-09 and Resources dictionary to complete the CloudFormation template as a Python dictionary named template.

AWS

template = {
    # Add AWSTemplateFormatVersion and Resources here
}
# Your code here

Need a hint?

Wrap the Resources dictionary inside a top-level template dictionary with the version key.