Cactus

Adapter to run an Azure Function HTTP triggers with a WSGI or ASGI Web Server.

How it works

Given the path of a folder containing a Function App, it builds a WSGI or ASGI App parsing the Function settings. The app simply calls the Function main according to the route/methods settings.

Supported Function

This software is meant to support only Function which use binding httpTrigger as input and http as output. No other binding types. This is not an Azure emulator.

Function App structure

V1

FunctionApp
|-- host.json
|-- function_1
|	|-- function.json
|	|-- __init__.py
|-- function_2
|	|-- function.json
|	|-- __init__.py

V2

FunctionApp
|-- host.json
|-- local.settings.json
|-- function_app.py

Installing

pip install pycactus
pip install pycactus[flask] # to use Flask as web framework
pip install pycactus[fastapi] # to use FastAPI as web framework

How to run

Create a file "app.py"

from cactus.appfactory import build_app
app = build_app("YourFunctionAppFolder")

Or, to use Flask as web framework:

from cactus.flask import build_app
app = build_app("YourFunctionAppFolder")

Or, for V2 projects:

from cactus.flask import build_app_v2
app = build_app_v2("YourFunctionAppFolder")

Or, for FastAPI projects:

from cactus.fastapi import build_app_v2
app = build_app_v2("YourFunctionAppFolder")

Run it with a WSGI or ASGI Web Server

gunicorn app:app
uwsgi --http localhost:7071 --module app:app
uvicorn app:app

Checkout the examples for more.

Using Flask blueprints

from cactus.flask import build_blueprint
from cactus.route_info import parse_project

app = flask.Flask(__name__)
b = build_blueprint("myfunctionapp", parse_project("/path"))
app.register_blueprint(b)

Or, for V2 projects:

from cactus.flask import build_blueprint
from cactus.route_info import parse_project_v2

app = flask.Flask(__name__)
b = build_blueprint("myfunctionapp", parse_project_v2("/path"))
app.register_blueprint(b)

Using FastAPI APIRouter

from cactus.fastapi import build_api_router
from cactus.route_info import parse_project_v2

app = fastapi.FastAPI()
b = build_api_router("myfunctionapp", parse_project_v2("/path"))
app.include_router(b)

Testing

This module is tested using Fir WSGI client.

# Create a virtual environment 
python3 -m venv venv
source venv/bin/activate
# Install requirements
pip install -r requirements -r test-requirements
# Run tests with coverage
python -m pytest tests --cov=cactus