Create a StringSession

telethon/sessions/string.py

@@ -0,0 +1,43 @@
+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.
+    """
+    def __init__(self, string=None):
+        super().__init__()
+        if string and string[0] != CURRENT_VERSION:
+            raise ValueError('Not a valid string')
+
+        ip_len = 4 if len(string) == 353 else 16
+        self._dc_id, ip, self._port, key = struct.unpack(
+            '>B{}sH256s'.format(ip_len), base64.urlsafe_b64decode(string[1:]))
+
+        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 + base64.urlsafe_b64encode(struct.pack(
+            '>B{}sH256s'.format(len(ip)),
+            self._dc_id,
+            ip,
+            self._port,
+            self._auth_key.key
+        )).decode('ascii')