Create OpenAPI spec plus Python application using it

Create an OpenAPI 3.0 defintion for us and program a modular backend in Python 3.6+ using it to show me how it works. We need a REST API for allowing our users to manage their webservers (e.g redirect rules) through a webinterface. The webinterface itself nor the real configuration of the webserver software is part of this job! You just validate the input of the user plus do some role-based authorization plus do some logic checks about the input (Does the input really makes sense? In real we will implement it later, but you have to show us how to do it.) This will be a long project but we will start with a small mockup which only implements the basics of the REST API: Write the OpenAPI 3.X spec for a few commands we need. (e.g.: create-webserver, add-redirect-rule) Use a Python framework for creating the web app. Do it in a modular way to make it easy for adding new commands! Not all users are allowed to do everything, so create a modular RBAC or ABAC to control access to the commands. Later we will use SAML or OAuth2 (SSO) for authentification, but for the start we will use basic auth for testing. The user / roles can be stored inside a DB (SQLite). The changes of the configuration by the user should be saved to human readable files and if you want more work add some kind of history (for more info see attached document). If you are able to use a DB for that too it would be nice, but NOT required. Still interested? Then see the attached document for a more information. (We currently have something like this, but it is a grown system over the years with a not-that-well-defined REST API. It is written in Perl and we will move to Python now.) If you bid tell me if you have done similar jobs and tell me (or do it privately in chat) which framework you will use (e.g. connexion, flask, Casbin,....) . Added at 2020-04-12: A short note: Because noone so far is talking about the history-problem (see attached file) a short note from myself after thinking a few minutes about this problem. While I wrote this project text I thought about something like: [login to view URL] [login to view URL] [login to view URL] [login to view URL] But after thinking about it again I came to a solution being much easier: As in [login to view URL] described we have the audit-log with entries like 'user X did Y on option Z'. So this file could be used as the needed history when we pimp it with a parsable format!