bulk-downloader-for-reddit/bdfr/oauth2.py
2022-12-03 15:11:17 +10:00

109 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(("0.0.0.0", 7634))
logger.log(9, "Server listening on 0.0.0.0:7634")
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}")