Telethon/telethon/sessions/string.py
2018-08-22 16:12:27 +02:00

54 lines
1.6 KiB
Python

import base64
import ipaddress
import struct
from .memory import MemorySession
from ..crypto import AuthKey
CURRENT_VERSION = '1'
class StringSession(MemorySession):
"""
This minimal session file can be easily saved and loaded as a string.
It is thought to be used where you don't want to create any on-disk
files but would still like to be able to save and load existing sessions
by other means.
You can use custom `encode` and `decode` functions, if present:
* `encode` definition must be ``def encode(value: bytes) -> str:``.
* `decode` definition must be ``def decode(value: str) -> bytes:``.
"""
encode = lambda x: base64.urlsafe_b64encode(x).decode('ascii')
decode = base64.urlsafe_b64decode
def __init__(self, string=None):
super().__init__()
if string:
if string[0] != CURRENT_VERSION:
raise ValueError('Not a valid string')
string = string[1:]
ip_len = 4 if len(string) == 352 else 16
self._dc_id, ip, self._port, key = struct.unpack(
'>B{}sH256s'.format(ip_len), StringSession.decode(string))
self._server_address = ipaddress.ip_address(ip).compressed
if any(key):
self._auth_key = AuthKey(key)
def save(self):
if not self._auth_key:
return ''
ip = ipaddress.ip_address(self._server_address).packed
return CURRENT_VERSION + StringSession.encode(struct.pack(
'>B{}sH256s'.format(len(ip)),
self._dc_id,
ip,
self._port,
self._auth_key.key
))