The following function can be used to force all routes in your view to be redirected to HTTPS.

@auth.before_request
def force_https():
    if not request.is_secure:
        url = request.url.replace('http://', 'https://', 1)
        return redirect(url, code=301)

Or, the Flask Security Guide recommends using Flask-Talisman. The pip install command can be used to install flask-talisman.

pip install flask-talisman

Or, you can specify the version to install

pip install flask-talisman==1.0.0

Or, better yet, use a requirements.txt file.

flask-talisman==1.0.0

And then install the packages using the requirements.txt file.

pip install --requirement requirements.txt

In your controller, import flask_talisman can then use the Talisman module to force HTTPS

from flask import Flask
from flask_talisman import Talisman

app = Flask(__name__)
Talisman(app)