bulk-downloader-for-reddit/bdfr/oauth2.py
2021-04-18 16:44:52 +03:00

108 lines
4.1 KiB
Python

#!/usr/bin/env python3
# coding=utf-8
import configparser
import logging
import random
import re
import socket
from pathlib import Path
import praw
import requests
from bdfr.exceptions import BulkDownloaderException, RedditAuthenticationError
logger = logging.getLogger(__name__)
class OAuth2Authenticator:
def __init__(self, wanted_scopes: set[str], client_id: str, client_secret: str):
self._check_scopes(wanted_scopes)
self.scopes = wanted_scopes
self.client_id = client_id
self.client_secret = client_secret
@staticmethod
def _check_scopes(wanted_scopes: set[str]):
response = requests.get('https://www.reddit.com/api/v1/scopes.json',
headers={'User-Agent': 'fetch-scopes test'})
known_scopes = [scope for scope, data in response.json().items()]
known_scopes.append('*')
for scope in wanted_scopes:
if scope not in known_scopes:
raise BulkDownloaderException(f'Scope {scope} is not known to reddit')
@staticmethod
def split_scopes(scopes: str) -> set[str]:
scopes = re.split(r'[,: ]+', scopes)
return set(scopes)
def retrieve_new_token(self) -> str:
reddit = praw.Reddit(
redirect_uri='http://localhost:7634',
user_agent='obtain_refresh_token for BDFR',
client_id=self.client_id,
client_secret=self.client_secret)
state = str(random.randint(0, 65000))
url = reddit.auth.url(self.scopes, state, 'permanent')
logger.warning('Authentication action required before the program can proceed')
logger.warning(f'Authenticate at {url}')
client = self.receive_connection()
data = client.recv(1024).decode('utf-8')
param_tokens = data.split(' ', 2)[1].split('?', 1)[1].split('&')
params = {key: value for (key, value) in [token.split('=') for token in param_tokens]}
if state != params['state']:
self.send_message(client)
raise RedditAuthenticationError(f'State mismatch in OAuth2. Expected: {state} Received: {params["state"]}')
elif 'error' in params:
self.send_message(client)
raise RedditAuthenticationError(f'Error in OAuth2: {params["error"]}')
self.send_message(client, "<script>alert('You can go back to terminal window now.')</script>")
refresh_token = reddit.auth.authorize(params["code"])
return refresh_token
@staticmethod
def receive_connection() -> socket.socket:
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server.bind(('localhost', 7634))
logger.log(9, 'Server listening on localhost:7634')
server.listen(1)
client = server.accept()[0]
server.close()
logger.log(9, 'Server closed')
return client
@staticmethod
def send_message(client: socket.socket, message: str):
client.send(f'HTTP/1.1 200 OK\r\n\r\n{message}'.encode('utf-8'))
client.close()
class OAuth2TokenManager(praw.reddit.BaseTokenManager):
def __init__(self, config: configparser.ConfigParser, config_location: Path):
super(OAuth2TokenManager, self).__init__()
self.config = config
self.config_location = config_location
def pre_refresh_callback(self, authorizer: praw.reddit.Authorizer):
if authorizer.refresh_token is None:
if self.config.has_option('DEFAULT', 'user_token'):
authorizer.refresh_token = self.config.get('DEFAULT', 'user_token')
logger.log(9, 'Loaded OAuth2 token for authoriser')
else:
raise RedditAuthenticationError('No auth token loaded in configuration')
def post_refresh_callback(self, authorizer: praw.reddit.Authorizer):
self.config.set('DEFAULT', 'user_token', authorizer.refresh_token)
with open(self.config_location, 'w') as file:
self.config.write(file, True)
logger.log(9, f'Written OAuth2 token from authoriser to {self.config_location}')