Serverless Framework Python HTTP API Image Converter on AWS

This repository contains a simple Python HTTP API application that uses the Serverless Framework to deploy to AWS.

It provides 2 endpoints:

• GET /upload-url - returns a pre-signed URL to upload an image to S3
• GET /{file_name} - downloads the image from S3 and returns it

It also contains an S3 object creation event that triggers a Lambda function to convert the image to a thumbnail.

Architecture

Deployment

# Install all necessary dependencies
npm install

# Deploy the application
npx serverless deploy

After deploying, you should see output similar to:

Deploying aws-python-image-converter to stage dev (us-east-1)

✔ Service deployed to stack aws-python-image-converter-dev (140s)

endpoint: GET - https://xxxxxxxxxx.execute-api.us-east-1.amazonaws.com/
functions:
  download: aws-python-image-converter-dev-download (2.3 kB)
  ...

Invocation

After successful deployment, you can call the created application via HTTP:

curl https://xxxxxxx.execute-api.us-east-1.amazonaws.com/

Which should result in response similar to the following (removed input content for brevity):

{
  "message": "Go Serverless v3.0! Your function executed successfully!",
  "input": {
    ...
  }
}

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": "{\n  \"message\": \"Go Serverless v3.0! Your function executed successfully!\",\n  \"input\": \"\"\n}"
}

You can start local API Gateway emulation with:

serverless offline

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