The official tutorial discusses deploying an app to production. One option is to use Waitress, a production WSGI server. Other servers include Gunicorn and uWSGI.
When running publicly rather than in development, you should not use the built-in development server (
flask run
). The development server is provided by Werkzeug for convenience, but is not designed to be particularly efficient, stable, or secure.Instead, use a production WSGI server. For example, to use Waitress, first install it in the virtual environment:
$ pip install waitress
You need to tell Waitress about your application, but it doesn’t use
FLASK_APP
like flask run does. You need to tell it to import and call the application factory to get an application object.$ waitress-serve --call 'flaskr:create_app' Serving on http://0.0.0.0:8080
Or you can use waitress.serve()
in the code instead of using the CLI command.
from flask import Flask
app = Flask(__name__)
@app.route("/")
def index():
return "<h1>Hello!</h1>"
if __name__ == "__main__":
from waitress import serve
serve(app, host="0.0.0.0", port=8080)
$ python hello.py