Writing a backend application

To build a token-gated web application, let’s use the FastAPI web framework:

(.venv) $ cd ../token-gated-smart-contract
(.venv) $ mkdir token-gated-backend
(.venv) $ cd token-gated-backend
(.venv) $ pip install fastapi pyjwt

The full code of the token-gated web application can be found here: https://github.com/PacktPublishing/Hands-On-Blockchain-for-Python-Developers--2nd-Edition/blob/main/chapter_17/token-gated-backend/token_gated_app.py.

Create a file named token_gated_app.py and add the following code:

from datetime import datetime, timedelta, timezone
from string import Template
import string
import json
import secrets
import os
from typing import Union
from ape import Contract
from ape import networks
from ethpm_types import ContractType
from fastapi import Depends, FastAPI, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from fastapi.middleware.cors import CORSMiddleware
import jwt
from pydantic import BaseModel...