Hello World Flask app: deploy a Python web app from GitHub

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A hello-world Flask (Python) web app. Deploy it free from its GitHub address with the MitsuruTech deploy a web app from GitHub feature: no account, nothing to install. It is small enough to be a first test of deploying to learntools.dev, and the steps are in the manual's guide to deploying Python, Node, Go and Java apps from GitHub.

Language        Python
Build           pip install --target .deps -r requirements.txt
Start           PYTHONPATH=.deps gunicorn --bind 0.0.0.0:$PORT app:app

Those are the platform's defaults; nothing here needs changing.

Why --target .deps. The build and the run happen in two different containers that share only this checkout, so dependencies have to land here rather than in the build container's own Python. A plain pip install reports success and then the app cannot import Flask.

Running it yourself

python -m venv .venv && .venv/bin/pip install -r requirements.txt
.venv/bin/python app.py

Licence

This work is licensed under CC BY-NC-SA 4.0. You may share it and adapt it for learning and teaching, if you credit Mitsuru Technologies Ltd, do not use it commercially, and share anything you make from it under the same licence. The full text is in the LICENSE file.

About

Made by Mitsuru Technologies for the MitsuruTech Learning Platform: Python, Java, Go, Node, SQL and Linux in the browser for schools and colleges, with container labs, web apps deployed from GitHub, and quizzes that mark themselves. Try code with no account in the playground.

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