Building a Serverless Function with Python on AWS
Serverless computing offers a powerful way to run code in the cloud without managing servers. AWS provides an easy way to get started with serverless functions, known as Lambdas. This tutorial will walk you through creating a serverless function using Python on AWS Lambda.

What is a Serverless Function?
Serverless functions allow you to execute code in response to events, such as HTTP requests, without managing the underlying infrastructure. Instead of deploying a full server, a serverless function runs in a cloud environment and scales automatically. For example, you could use a serverless function to pull data from a database or store a GPS location, all without the complexity of maintaining a server.
AWS calls their serverless functions Lambdas. In this tutorial, we’ll build and test a simple Python Lambda function to illustrate how serverless functions can save time and resources.
Step 1: Set Up Your AWS Account
Before you start, ensure you have an AWS account. If you don’t already have one, creating an account is the first step. Once you’re ready, log into the AWS Console.
Step 2: Access the Lambda Service
Once logged in, you’ll find Lambda listed under the Compute section. If it doesn’t appear on the homepage, click on “View all services” and search for Lambda. Clicking on it will take you to the Lambda dashboard, where you can manage your serverless functions.
Step 3: Create a New Lambda Function
On the Lambda dashboard, click the Create Function button to start the setup process. You’ll be given several options; select Author from scratch.
Next, you’ll need to:
- Name your function – Give your Lambda a unique name.
- Choose a runtime – For this tutorial, select Python 3.9.
- Enable function URL – This will create a public web address for your function.
- Set authentication – Choose NONE for this example. Note that this is not a secure setup and should only be used for demo purposes.
Once you’re done, click Create function to finish the setup. Your Lambda function is now ready to be tested.
Step 4: Testing Your Lambda Function
Once your function is created, you’ll be taken to the function’s management page. On the right-hand side, you will see a public URL for your Lambda function. Click the URL to send a GET request directly from your browser.
At this point, you have successfully created a basic serverless function in AWS. However, let’s extend its capabilities by making it handle more complex requests.
Step 5: Testing with Postman
For more interactive testing, we can use Postman. Postman allows you to send various types of requests to your Lambda function. If you don’t have Postman, you can easily sign up for a free account.
- Create a new POST request in Postman.
- Paste the Lambda function URL into the request URL field.
- Set the request type to POST and add a body with the data you want to send.
To process the incoming data, modify your Lambda function’s code as follows:
import json
def lambda_handler(event, context):
request = event['body']
request_obj = json.loads(request)
return {
'statusCode': 200,
'headers': {'Content-Type': 'application/json'},
'body': "{}, {} {}!".format(request_obj['Greeting'], request_obj['Title'], request_obj['Name'])
}
This updated code will allow your Lambda function to parse the incoming JSON data and respond with a formatted message. Once you’ve updated the code, click Deploy to apply the changes.
Step 6: Verify the Result
After deploying the updated Lambda, send the POST request from Postman. Your Lambda function should return a response with the formatted message based on the input you provided.
Congratulations, you’ve successfully built and tested a serverless function on AWS using Python!
Why Use Serverless Functions?
Serverless functions, like AWS Lambda, simplify cloud development by reducing the need to manage infrastructure. They automatically scale, and you only pay for the compute power you use. This makes them an ideal choice for event-driven applications, such as APIs, IoT, and microservices.
In addition, integrating serverless computing with tools like DevOps, Cloud services, and microservices can help streamline your infrastructure management. ZippyOPS provides expert consulting, implementation, and managed services in these areas, ensuring smooth DevOps, DevSecOps, DataOps, and more for your organization. For more information on how ZippyOPS can help, check out our services.
Advanced AWS Lambda Use Cases
Serverless functions are highly versatile. For instance, you could integrate AWS Lambda with other cloud services like API Gateway, S3, or DynamoDB to build fully serverless applications. These integrations allow you to create powerful, scalable systems with minimal overhead.
As businesses move towards cloud-native architectures, serverless functions can support automated operations (Automated Ops), AIOps, MLOps, and even advanced use cases in Infrastructure and Security. ZippyOPS’ solutions integrate these capabilities to ensure that your systems are highly secure and perform optimally.
Learn more about the products and solutions that ZippyOPS offers to enhance your cloud and serverless infrastructure here.
Conclusion
In summary, building a serverless function with AWS Lambda and Python is straightforward and effective for many cloud applications. Whether you’re creating an API, processing data, or building microservices, AWS Lambda offers a scalable, cost-effective solution.
For businesses looking to leverage serverless computing, ZippyOPS provides comprehensive consulting and managed services in cloud computing, DevOps, and infrastructure security. If you need expert guidance, reach out to us at sales@zippyops.com.



