Deploy Python Falcon in AWS Lambda

1. create the lambda handler

Create a Falcon API in service.py,

# service.py
class QuoteResource:
    def on_get(self, req, resp):
        quote = {
            'quote': "Blabetiblou",
            'author': 'Raphaël JOIE'
        }

        resp.media = quote

api = falcon.App()
api.add_route('/quote', QuoteResource())

# requirements.txt
falcon

and import the API in a lambda_function.py file

# lambda_function.py

from service import api
from python_falcon_lambda import lambda_handler

lambda_handler = lambda_handler(api)

2. Build the lambda zip

Run Python Lambda Builder to package

$ docker run \
    --volume $(pwd):/workdir \
    --platform linux/amd64 \
    raphaeljoie/python-lambda-builder \
    ".terraform/*"

to generate build/lambda.zip

3. Deploy

Prepare the deployment

provider "aws" {
  region = "eu-west-1"
}

module "api" {
  source = "git:///python-falcon-lambda/terraform"

  lambda_bucket_name = "shared-lambda-bucket-name"
  lambda_name = "my-lambda"
  lambda_version = "v0.1.0"
}

output "api_url" {
  value = module.api.api_url
}

and terraform apply

TODO

• Docker builder is using python3.8 => should use the same for lambda runner
• adapt payload v2.0 and v1.0 https://docs.aws.amazon.com/apigateway/latest/developerguide/http-api-develop-integrations-lambda.html