Serverless Framework Python HTTP API on AWS

This template includes a DynamoDB table and two Lambdas for users (usersList, usersCreate), plus hello for GET /. Function definitions live in functions.yaml and are merged via functions: ${file(./functions.yaml)} in serverless.yml.

• GET /users — returns up to 100 users (scan; suitable for demos only).
• POST /users — JSON body {"email":"you@example.com"}; creates a row with userId (UUID), email, and createdAt.

The table name is injected at deploy time as USERS_TABLE_NAME. No VPC or extra Python dependencies are required (boto3 is in the Lambda runtime).

This template demonstrates how to make a simple HTTP API with Python on AWS Lambda using the Serverless Framework. For more examples, see the serverless/examples repository.

Usage

Deployment

serverless deploy

After deploying, you should see output similar to:

Deploying "aws-python-http-api" to stage "dev" (us-east-1)

✔ Service deployed to stack aws-python-http-api-dev (85s)

endpoint: GET - https://6ewcye3q4d.execute-api.us-east-1.amazonaws.com/
functions:
  hello: aws-python-http-api-dev-hello (2.3 kB)

Note: In current form, after deployment, your API is public and can be invoked by anyone. For production deployments, you might want to configure an authorizer. For details on how to do that, refer to http event docs.

Invocation

After successful deployment, you can call the created application via HTTP (replace the host with your deploy output):

curl https://xxxxxxx.execute-api.us-east-1.amazonaws.com/
curl https://xxxxxxx.execute-api.us-east-1.amazonaws.com/users
curl -X POST https://xxxxxxx.execute-api.us-east-1.amazonaws.com/users \
  -H "Content-Type: application/json" \
  -d '{"email":"you@example.com"}'

GET / returns a hello message. GET /users and POST /users use DynamoDB.

Which should result in response similar to the following for GET /:

{
  "message": "Go Serverless v4.0! Your function executed successfully!"
}

Local development

You can invoke your function locally by using the following command:

serverless invoke local --function hello

Which should result in response similar to the following:

{
  "statusCode": 200,
  "body": "{\"message\": \"Go Serverless v4.0! Your function executed successfully!\"}"
}

Alternatively, it is also possible to emulate API Gateway and Lambda locally by using serverless-offline plugin. In order to do that, execute the following command:

serverless plugin install -n serverless-offline

It will add the serverless-offline plugin to devDependencies in package.json file as well as will add it to plugins in serverless.yml.

After installation, you can start local emulation with:

serverless offline

To learn more about the capabilities of serverless-offline, please refer to its GitHub repository.

Bundling dependencies

In case you would like to include 3rd party dependencies, you will need to use a plugin called serverless-python-requirements. You can set it up by running the following command:

serverless plugin install -n serverless-python-requirements

Running the above will automatically add serverless-python-requirements to plugins section in your serverless.yml file and add it as a devDependency to package.json file. The package.json file will be automatically created if it doesn't exist beforehand. Now you will be able to add your dependencies to requirements.txt file (Pipfile and pyproject.toml is also supported but requires additional configuration) and they will be automatically injected to Lambda package during build process. For more details about the plugin's configuration, please refer to official documentation.