awsgi2

====== awsgi2

AWSGI allows you to use WSGI-compatible middleware and frameworks like Flask and Django with the AWS API Gateway/Lambda proxy integration <https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-set-up-simple-proxy.html>_.

This is an improved fork of original aws-wsgi <https://github.com/slank/awsgi>_.

Installation

awsgi2 is available from PyPI as awsgi2::

pip install awsgi2

Examples

Flask ^^^^^

.. code-block:: python

import awsgi2
from flask import (
    Flask,
    jsonify,
)

app = Flask(__name__)


@app.route('/')
def index():
    return jsonify(status=200, message='OK')


def lambda_handler(event, context):
    return awsgi2.response(app, event, context, base64_content_types={"image/png"})

Django ^^^^^^

.. code-block:: python

import os
import awsgi2

from django.core.wsgi import get_wsgi_application

# my_app_directory/settings.py is a vanilla Django settings file, created by "django-admin startproject".
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'my_app_directory.settings')
# In the settings.py file, you may find it useful to include this setting to remove
# Django's need for SQLite, which is currently (2020-11-17) outdated in the Lambda runtime image
# DATABASES = { 'default': { 'ENGINE': 'django.db.backends.dummy', } }

application = get_wsgi_application()

def lambda_handler(event, context):
    return awsgi2.response(application, event, context, base64_content_types={"image/png"})

Docker

For more controlled deployments and to get rid of "works on my computer" -syndrome, we always make sure our software works under docker.

It's also a quick way to get started with a standard development environment.

SSH agent forwarding ^^^^^^^^^^^^^^^^^^^^

We need buildkit_::

export DOCKER_BUILDKIT=1

.. _buildkit: https://docs.docker.com/develop/develop-images/build_enhancements/

And also the exact way for forwarding agent to running instance is different on OSX::

export DOCKER_SSHAGENT="-v /run/host-services/ssh-auth.sock:/run/host-services/ssh-auth.sock -e SSH_AUTH_SOCK=/run/host-services/ssh-auth.sock"

and Linux::

export DOCKER_SSHAGENT="-v $SSH_AUTH_SOCK:$SSH_AUTH_SOCK -e SSH_AUTH_SOCK"

Creating a development container ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Build image, create container and start it::

docker build --ssh default --target devel_shell -t awsgi2:devel_shell .
docker create --name awsgi2_devel -v `pwd`":/app" -it `echo $DOCKER_SSHAGENT` awsgi2:devel_shell
docker start -i awsgi2_devel

pre-commit considerations ^^^^^^^^^^^^^^^^^^^^^^^^^

If working in Docker instead of native env you need to run the pre-commit checks in docker too::

docker exec -i awsgi2_devel /bin/bash -c "pre-commit install"
docker exec -i awsgi2_devel /bin/bash -c "pre-commit run --all-files"

You need to have the container running, see above. Or alternatively use the docker run syntax but using the running container is faster::

docker run --rm -it -v `pwd`":/app" awsgi2:devel_shell -c "pre-commit run --all-files"

Test suite ^^^^^^^^^^

You can use the devel shell to run py.test when doing development, for CI use the "tox" target in the Dockerfile::

docker build --ssh default --target tox -t awsgi2:tox .
docker run --rm -it -v `pwd`":/app" `echo $DOCKER_SSHAGENT` awsgi2:tox

Development

TLDR:

• Create and activate a Python 3.8 virtualenv (assuming virtualenvwrapper)::

  mkvirtualenv -p which python3.8 my_virtualenv

• change to a branch::

  git checkout -b my_branch

• install Poetry: https://python-poetry.org/docs/#installation

• Install project deps and pre-commit hooks::

  poetry install pre-commit install pre-commit run --all-files

• Ready to go.

Remember to activate your virtualenv whenever working on the repo, this is needed because pylint and mypy pre-commit hooks use the "system" python for now (because reasons).