main.py

import base64
import hashlib
import os
import re
import json
import requests
from requests.auth import AuthBase, HTTPBasicAuth
from requests_oauthlib import OAuth2Session, TokenUpdated
from flask import Flask, request, redirect, session, url_for, render_template

from dotenv import get_key, load_dotenv, set_key

load_dotenv('./.env')

app = Flask(__name__)
app.secret_key = os.urandom(50)

client_id = os.getenv('TWITTER_CLIENT_ID')
client_secret = os.getenv('TWITTER_CLIENT_SECRET')
auth_url = "https://twitter.com/i/oauth2/authorize"
token_url = "https://api.twitter.com/2/oauth2/token"
redirect_uri = 'http://127.0.0.1:5000/oauth/callback'

scopes = ["tweet.read", "users.read", "tweet.write", "offline.access"]

code_verifier = base64.urlsafe_b64encode(os.urandom(30)).decode("utf-8")
code_verifier = re.sub("[^a-zA-Z0-9]+", "", code_verifier)

code_challenge = hashlib.sha256(code_verifier.encode("utf-8")).digest()
code_challenge = base64.urlsafe_b64encode(code_challenge).decode("utf-8")
code_challenge = code_challenge.replace("=", "")


def make_token():
    return OAuth2Session(client_id, redirect_uri=redirect_uri, scope=scopes)

def post_tweet(payload, token):
    print("Tweeting!!")
    return requests.request(
        "POST",
        "https://api.twitter.com/2/tweets",
        json=payload,
        headers={
            "Authorization": f"Bearer {token['access_token']}",
            "Content-Type": "application/json"
        },
        timeout=120
    )

@app.route('/')
def demo():
    global twitter
    twitter = make_token()
    authorization_url, state = twitter.authorization_url(
        auth_url,
        code_challenge=code_challenge,
        code_challenge_method="S256"
    )
    session["oauth_state"] = state
    return redirect(authorization_url)

@app.route("/oauth/callback", methods=["GET"])
def callback():
    code = request.args.get("code")
    token = twitter.fetch_token(
        token_url=token_url,
        client_secret=client_secret,
        code_verifier=code_verifier,
        code=code,
    )
    print(f"TOKEN IS:\n{token}")
    st_token = f'"{token}"'

    set_key('./.env', 'TOKEN', st_token)
    # doggie_fact = parse_dog_fact()
    # payload = {"text": "Hello World!"}
    # response = post_tweet(payload, token).json()
    # return response


if __name__ == "__main__":
    app.run(
        debug=True
    )