Updated: 08 August 2022
See https://flask.palletsprojects.com/en/2.1.x/quickstart/
Create an environment
python3 -m venv venv
Activate the environment
. venv/bin/activate
Deactivate the environment
deactivate
Install Flask
pip install Flask
hello.py
# Import the Flask class - an instance of this class
# will be a WSGI application.
from flask import Flask
# Next we create an instance of this class. The first
# argument is the name of the application’s module or
# package. __name__ is a convenient shortcut for this
# that is appropriate for most cases. This is needed so
# that Flask knows where to look for resources such as
# templates and static files.
app = Flask(__name__)
@app.route("/")
def hello_world():
return "<p>Hello, World!</p>"
run
export FLASK_APP=hello
flask run
If debugger disabled or you trust the users on your network, make the server publicly available
flask run --host=0.0.0.0
The debugger allows executing arbitrary Python code from the browser. It is protected by a pin, but still represents a major security risk.
export FLASK_ENV=development
flask run