Abstract Session class (merge #657 from tulir/sessions)

optional-requirements.txt

@@ -1,3 +1,4 @@
 cryptg
 pysocks
 hachoir3
+sqlalchemy

readthedocs/extra/advanced-usage/sessions.rst

@@ -25,29 +25,89 @@ file, so that you can quickly access them by username or phone number.
 
 If you're not going to work with updates, or don't need to cache the
 ``access_hash`` associated with the entities' ID, you can disable this
-by setting ``client.session.save_entities = False``, or pass it as a
-parameter to the ``TelegramClient``.
+by setting ``client.session.save_entities = False``.
 
-If you don't want to save the files as a database, you can also create
-your custom ``Session`` subclass and override the ``.save()`` and ``.load()``
-methods. For example, you could save it on a database:
+Custom Session Storage
+----------------------
+
+If you don't want to use the default SQLite session storage, you can also use
+one of the other implementations or implement your own storage.
+
+To use a custom session storage, simply pass the custom session instance to
+``TelegramClient`` instead of the session name.
+
+Currently, there are three implementations of the abstract ``Session`` class:
+* MemorySession. Stores session data in Python variables.
+* SQLiteSession, the default. Stores sessions in their own SQLite databases.
+* AlchemySession. Stores all sessions in a single database via SQLAlchemy.
+
+Using AlchemySession
+~~~~~~~~~~~~~~~~~~~~
+The AlchemySession implementation can store multiple Sessions in the same
+database, but to do this, each session instance needs to have access to the
+same models and database session.
+
+To get started, you need to create an ``AlchemySessionContainer`` which will
+contain that shared data. The simplest way to use ``AlchemySessionContainer``
+is to simply pass it the database URL:
 
     .. code-block:: python
 
-        class DatabaseSession(Session):
-            def save():
-                # serialize relevant data to the database
+        container = AlchemySessionContainer('mysql://user:pass@localhost/telethon')
 
-            def load():
-                # load relevant data to the database
+If you already have SQLAlchemy set up for your own project, you can also pass
+the engine separately:
+
+    .. code-block:: python
+
+        my_sqlalchemy_engine = sqlalchemy.create_engine('...')
+        container = AlchemySessionContainer(engine=my_sqlalchemy_engine)
+
+By default, the session container will manage table creation/schema updates/etc
+automatically. If you want to manage everything yourself, you can pass your
+SQLAlchemy Session and ``declarative_base`` instances and set ``manage_tables``
+to ``False``:
+
+    .. code-block:: python
+
+        from sqlalchemy.ext.declarative import declarative_base
+        from sqlalchemy import orm
+        import sqlalchemy
+
+        ...
+
+        session_factory = orm.sessionmaker(bind=my_sqlalchemy_engine)
+        session = session_factory()
+        my_base = declarative_base()
+
+        ...
+
+        container = AlchemySessionContainer(session=session, table_base=my_base, manage_tables=False)
+
+You always need to provide either ``engine`` or ``session`` to the container.
+If you set ``manage_tables=False`` and provide a ``session``, ``engine`` is not
+needed. In any other case, ``engine`` is always required.
+
+After you have your ``AlchemySessionContainer`` instance created, you can
+create new sessions by calling ``new_session``:
+
+    .. code-block:: python
+
+        session = container.new_session('some session id')
+        client = TelegramClient(session)
+
+where ``some session id`` is an unique identifier for the session.
+
+Creating your own storage
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The easiest way to create your own implementation is to use MemorySession as
+the base and check out how ``SQLiteSession`` or ``AlchemySession`` work. You
+can find the relevant Python files under the ``sessions`` directory.
 
 
-You should read the ````session.py```` source file to know what "relevant
-data" you need to keep track of.
-
-
-Sessions and Heroku
--------------------
+SQLite Sessions and Heroku
+--------------------------
 
 You probably have a newer version of SQLite installed (>= 3.8.2). Heroku uses
 SQLite 3.7.9 which does not support ``WITHOUT ROWID``. So, if you generated
@@ -59,8 +119,8 @@ session file on your Heroku dyno itself. The most complicated is creating
 a custom buildpack to install SQLite >= 3.8.2.
 
 
-Generating a Session File on a Heroku Dyno
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Generating a SQLite Session File on a Heroku Dyno
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. note::
     Due to Heroku's ephemeral filesystem all dynamically generated

setup.py

@@ -151,7 +151,8 @@ def main():
             ]),
             install_requires=['pyaes', 'rsa'],
             extras_require={
-                'cryptg': ['cryptg']
+                'cryptg': ['cryptg'],
+                'sqlalchemy': ['sqlalchemy']
             }
         )
 

telethon/network/mtproto_sender.py

@@ -402,13 +402,13 @@ class MtProtoSender:
         elif bad_msg.error_code == 32:
             # msg_seqno too low, so just pump it up by some "large" amount
             # TODO A better fix would be to start with a new fresh session ID
-            self.session._sequence += 64
+            self.session.sequence += 64
             __log__.info('Attempting to set the right higher sequence')
             self._resend_request(bad_msg.bad_msg_id)
             return True
         elif bad_msg.error_code == 33:
             # msg_seqno too high never seems to happen but just in case
-            self.session._sequence -= 16
+            self.session.sequence -= 16
             __log__.info('Attempting to set the right lower sequence')
             self._resend_request(bad_msg.bad_msg_id)
             return True

telethon/sessions/__init__.py

@@ -0,0 +1,4 @@
+from .abstract import Session
+from .memory import MemorySession
+from .sqlite import SQLiteSession
+from .sqlalchemy import AlchemySessionContainer, AlchemySession

telethon/sessions/abstract.py

@@ -0,0 +1,147 @@
+from abc import ABC, abstractmethod
+import time
+import struct
+import os
+
+
+class Session(ABC):
+    def __init__(self):
+        self.id = struct.unpack('q', os.urandom(8))[0]
+
+        self._sequence = 0
+        self._last_msg_id = 0
+        self._time_offset = 0
+        self._salt = 0
+        self._report_errors = True
+        self._flood_sleep_threshold = 60
+
+    def clone(self, to_instance=None):
+        cloned = to_instance or self.__class__()
+        cloned._report_errors = self.report_errors
+        cloned._flood_sleep_threshold = self.flood_sleep_threshold
+        return cloned
+
+    @abstractmethod
+    def set_dc(self, dc_id, server_address, port):
+        raise NotImplementedError
+
+    @property
+    @abstractmethod
+    def server_address(self):
+        raise NotImplementedError
+
+    @property
+    @abstractmethod
+    def port(self):
+        raise NotImplementedError
+
+    @property
+    @abstractmethod
+    def auth_key(self):
+        raise NotImplementedError
+
+    @auth_key.setter
+    @abstractmethod
+    def auth_key(self, value):
+        raise NotImplementedError
+
+    @abstractmethod
+    def close(self):
+        raise NotImplementedError
+
+    @abstractmethod
+    def save(self):
+        raise NotImplementedError
+
+    @abstractmethod
+    def delete(self):
+        raise NotImplementedError
+
+    @classmethod
+    @abstractmethod
+    def list_sessions(cls):
+        raise NotImplementedError
+
+    @abstractmethod
+    def process_entities(self, tlo):
+        raise NotImplementedError
+
+    @abstractmethod
+    def get_input_entity(self, key):
+        raise NotImplementedError
+
+    @abstractmethod
+    def cache_file(self, md5_digest, file_size, instance):
+        raise NotImplementedError
+
+    @abstractmethod
+    def get_file(self, md5_digest, file_size, cls):
+        raise NotImplementedError
+
+    @property
+    def salt(self):
+        return self._salt
+
+    @salt.setter
+    def salt(self, value):
+        self._salt = value
+
+    @property
+    def report_errors(self):
+        return self._report_errors
+
+    @report_errors.setter
+    def report_errors(self, value):
+        self._report_errors = value
+
+    @property
+    def time_offset(self):
+        return self._time_offset
+
+    @time_offset.setter
+    def time_offset(self, value):
+        self._time_offset = value
+
+    @property
+    def flood_sleep_threshold(self):
+        return self._flood_sleep_threshold
+
+    @flood_sleep_threshold.setter
+    def flood_sleep_threshold(self, value):
+        self._flood_sleep_threshold = value
+
+    @property
+    def sequence(self):
+        return self._sequence
+
+    @sequence.setter
+    def sequence(self, value):
+        self._sequence = value
+
+    def get_new_msg_id(self):
+        """Generates a new unique message ID based on the current
+           time (in ms) since epoch"""
+        now = time.time() + self._time_offset
+        nanoseconds = int((now - int(now)) * 1e+9)
+        new_msg_id = (int(now) << 32) | (nanoseconds << 2)
+
+        if self._last_msg_id >= new_msg_id:
+            new_msg_id = self._last_msg_id + 4
+
+        self._last_msg_id = new_msg_id
+
+        return new_msg_id
+
+    def update_time_offset(self, correct_msg_id):
+        now = int(time.time())
+        correct = correct_msg_id >> 32
+        self._time_offset = correct - now
+        self._last_msg_id = 0
+
+    def generate_sequence(self, content_related):
+        if content_related:
+            result = self._sequence * 2 + 1
+            self._sequence += 1
+            return result
+        else:
+            return self._sequence * 2

telethon/sessions/memory.py

@@ -0,0 +1,204 @@
+from enum import Enum
+
+from .. import utils
+from .abstract import Session
+from ..tl import TLObject
+
+from ..tl.types import (
+    PeerUser, PeerChat, PeerChannel,
+    InputPeerUser, InputPeerChat, InputPeerChannel,
+    InputPhoto, InputDocument
+)
+
+
+class _SentFileType(Enum):
+    DOCUMENT = 0
+    PHOTO = 1
+
+    @staticmethod
+    def from_type(cls):
+        if cls == InputDocument:
+            return _SentFileType.DOCUMENT
+        elif cls == InputPhoto:
+            return _SentFileType.PHOTO
+        else:
+            raise ValueError('The cls must be either InputDocument/InputPhoto')
+
+
+class MemorySession(Session):
+    def __init__(self):
+        super().__init__()
+
+        self._dc_id = None
+        self._server_address = None
+        self._port = None
+        self._auth_key = None
+
+        self._files = {}
+        self._entities = set()
+
+    def set_dc(self, dc_id, server_address, port):
+        self._dc_id = dc_id
+        self._server_address = server_address
+        self._port = port
+
+    @property
+    def server_address(self):
+        return self._server_address
+
+    @property
+    def port(self):
+        return self._port
+
+    @property
+    def auth_key(self):
+        return self._auth_key
+
+    @auth_key.setter
+    def auth_key(self, value):
+        self._auth_key = value
+
+    def close(self):
+        pass
+
+    def save(self):
+        pass
+
+    def delete(self):
+        pass
+
+    @classmethod
+    def list_sessions(cls):
+        raise NotImplementedError
+
+    def _entity_values_to_row(self, id, hash, username, phone, name):
+        return id, hash, username, phone, name
+
+    def _entity_to_row(self, e):
+        if not isinstance(e, TLObject):
+            return
+        try:
+            p = utils.get_input_peer(e, allow_self=False)
+            marked_id = utils.get_peer_id(p)
+        except ValueError:
+            return
+
+        if isinstance(p, (InputPeerUser, InputPeerChannel)):
+            if not p.access_hash:
+                # Some users and channels seem to be returned without
+                # an 'access_hash', meaning Telegram doesn't want you
+                # to access them. This is the reason behind ensuring
+                # that the 'access_hash' is non-zero. See issue #354.
+                # Note that this checks for zero or None, see #392.
+                return
+            else:
+                p_hash = p.access_hash
+        elif isinstance(p, InputPeerChat):
+            p_hash = 0
+        else:
+            return
+
+        username = getattr(e, 'username', None) or None
+        if username is not None:
+            username = username.lower()
+        phone = getattr(e, 'phone', None)
+        name = utils.get_display_name(e) or None
+        return self._entity_values_to_row(marked_id, p_hash, username, phone, name)
+
+    def _entities_to_rows(self, tlo):
+        if not isinstance(tlo, TLObject) and utils.is_list_like(tlo):
+            # This may be a list of users already for instance
+            entities = tlo
+        else:
+            entities = []
+            if hasattr(tlo, 'chats') and utils.is_list_like(tlo.chats):
+                entities.extend(tlo.chats)
+            if hasattr(tlo, 'users') and utils.is_list_like(tlo.users):
+                entities.extend(tlo.users)
+            if not entities:
+                return
+
+        rows = []  # Rows to add (id, hash, username, phone, name)
+        for e in entities:
+            row = self._entity_to_row(e)
+            if row:
+                rows.append(row)
+        return rows
+
+    def process_entities(self, tlo):
+        self._entities += set(self._entities_to_rows(tlo))
+
+    def get_entity_rows_by_phone(self, phone):
+        rows = [(id, hash) for id, hash, _, found_phone, _
+                in self._entities if found_phone == phone]
+        return rows[0] if rows else None
+
+    def get_entity_rows_by_username(self, username):
+        rows = [(id, hash) for id, hash, found_username, _, _
+                in self._entities if found_username == username]
+        return rows[0] if rows else None
+
+    def get_entity_rows_by_name(self, name):
+        rows = [(id, hash) for id, hash, _, _, found_name
+                in self._entities if found_name == name]
+        return rows[0] if rows else None
+
+    def get_entity_rows_by_id(self, id):
+        rows = [(id, hash) for found_id, hash, _, _, _
+                in self._entities if found_id == id]
+        return rows[0] if rows else None
+
+    def get_input_entity(self, key):
+        try:
+            if key.SUBCLASS_OF_ID in (0xc91c90b6, 0xe669bf46, 0x40f202fd):
+                # hex(crc32(b'InputPeer', b'InputUser' and b'InputChannel'))
+                # We already have an Input version, so nothing else required
+                return key
+            # Try to early return if this key can be casted as input peer
+            return utils.get_input_peer(key)
+        except (AttributeError, TypeError):
+            # Not a TLObject or can't be cast into InputPeer
+            if isinstance(key, TLObject):
+                key = utils.get_peer_id(key)
+
+        result = None
+        if isinstance(key, str):
+            phone = utils.parse_phone(key)
+            if phone:
+                result = self.get_entity_rows_by_phone(phone)
+            else:
+                username, _ = utils.parse_username(key)
+                if username:
+                    result = self.get_entity_rows_by_username(username)
+
+        if isinstance(key, int):
+            result = self.get_entity_rows_by_id(key)
+
+        if not result and isinstance(key, str):
+            result = self.get_entity_rows_by_name(key)
+
+        if result:
+            i, h = result  # unpack resulting tuple
+            i, k = utils.resolve_id(i)  # removes the mark and returns kind
+            if k == PeerUser:
+                return InputPeerUser(i, h)
+            elif k == PeerChat:
+                return InputPeerChat(i)
+            elif k == PeerChannel:
+                return InputPeerChannel(i, h)
+        else:
+            raise ValueError('Could not find input entity with key ', key)
+
+    def cache_file(self, md5_digest, file_size, instance):
+        if not isinstance(instance, (InputDocument, InputPhoto)):
+            raise TypeError('Cannot cache %s instance' % type(instance))
+        key = (md5_digest, file_size, _SentFileType.from_type(instance))
+        value = (instance.id, instance.access_hash)
+        self._files[key] = value
+
+    def get_file(self, md5_digest, file_size, cls):
+        key = (md5_digest, file_size, _SentFileType.from_type(cls))
+        try:
+            return self._files[key]
+        except KeyError:
+            return None

telethon/sessions/sqlalchemy.py

@@ -0,0 +1,225 @@
+try:
+    from sqlalchemy.ext.declarative import declarative_base
+    from sqlalchemy import Column, String, Integer, BLOB, orm
+    import sqlalchemy as sql
+except ImportError:
+    sql = None
+    pass
+
+from ..crypto import AuthKey
+from ..tl.types import InputPhoto, InputDocument
+
+from .memory import MemorySession, _SentFileType
+
+LATEST_VERSION = 1
+
+
+class AlchemySessionContainer:
+    def __init__(self, engine=None, session=None, table_prefix='',
+                 table_base=None, manage_tables=True):
+        if not sql:
+            raise ImportError('SQLAlchemy not imported')
+        if isinstance(engine, str):
+            engine = sql.create_engine(engine)
+
+        self.db_engine = engine
+        if not session:
+            db_factory = orm.sessionmaker(bind=self.db_engine)
+            self.db = orm.scoping.scoped_session(db_factory)
+        else:
+            self.db = session
+
+        table_base = table_base or declarative_base()
+        (self.Version, self.Session, self.Entity,
+         self.SentFile) = self.create_table_classes(self.db, table_prefix,
+                                                    table_base)
+
+        if manage_tables:
+            table_base.metadata.bind = self.db_engine
+            if not self.db_engine.dialect.has_table(self.db_engine,
+                                                    self.Version.__tablename__):
+                table_base.metadata.create_all()
+                self.db.add(self.Version(version=LATEST_VERSION))
+                self.db.commit()
+            else:
+                self.check_and_upgrade_database()
+
+    @staticmethod
+    def create_table_classes(db, prefix, Base):
+        class Version(Base):
+            query = db.query_property()
+            __tablename__ = '{prefix}version'.format(prefix=prefix)
+            version = Column(Integer, primary_key=True)
+
+        class Session(Base):
+            query = db.query_property()
+            __tablename__ = '{prefix}sessions'.format(prefix=prefix)
+
+            session_id = Column(String, primary_key=True)
+            dc_id = Column(Integer, primary_key=True)
+            server_address = Column(String)
+            port = Column(Integer)
+            auth_key = Column(BLOB)
+
+        class Entity(Base):
+            query = db.query_property()
+            __tablename__ = '{prefix}entities'.format(prefix=prefix)
+
+            session_id = Column(String, primary_key=True)
+            id = Column(Integer, primary_key=True)
+            hash = Column(Integer, nullable=False)
+            username = Column(String)
+            phone = Column(Integer)
+            name = Column(String)
+
+        class SentFile(Base):
+            query = db.query_property()
+            __tablename__ = '{prefix}sent_files'.format(prefix=prefix)
+
+            session_id = Column(String, primary_key=True)
+            md5_digest = Column(BLOB, primary_key=True)
+            file_size = Column(Integer, primary_key=True)
+            type = Column(Integer, primary_key=True)
+            id = Column(Integer)
+            hash = Column(Integer)
+
+        return Version, Session, Entity, SentFile
+
+    def check_and_upgrade_database(self):
+        row = self.Version.query.all()
+        version = row[0].version if row else 1
+        if version == LATEST_VERSION:
+            return
+
+        self.Version.query.delete()
+
+        # Implement table schema updates here and increase version
+
+        self.db.add(self.Version(version=version))
+        self.db.commit()
+
+    def new_session(self, session_id):
+        return AlchemySession(self, session_id)
+
+    def list_sessions(self):
+        return
+
+    def save(self):
+        self.db.commit()
+
+
+class AlchemySession(MemorySession):
+    def __init__(self, container, session_id):
+        super().__init__()
+        self.container = container
+        self.db = container.db
+        self.Version, self.Session, self.Entity, self.SentFile = (
+            container.Version, container.Session, container.Entity,
+            container.SentFile)
+        self.session_id = session_id
+        self._load_session()
+
+    def _load_session(self):
+        sessions = self._db_query(self.Session).all()
+        session = sessions[0] if sessions else None
+        if session:
+            self._dc_id = session.dc_id
+            self._server_address = session.server_address
+            self._port = session.port
+            self._auth_key = AuthKey(data=session.auth_key)
+
+    def clone(self, to_instance=None):
+        cloned = to_instance or self.__class__(self.container, self.session_id)
+        return super().clone(cloned)
+
+    def set_dc(self, dc_id, server_address, port):
+        super().set_dc(dc_id, server_address, port)
+        self._update_session_table()
+
+        sessions = self._db_query(self.Session).all()
+        session = sessions[0] if sessions else None
+        if session and session.auth_key:
+            self._auth_key = AuthKey(data=session.auth_key)
+        else:
+            self._auth_key = None
+
+    @MemorySession.auth_key.setter
+    def auth_key(self, value):
+        self._auth_key = value
+        self._update_session_table()
+
+    def _update_session_table(self):
+        self.Session.query.filter(
+            self.Session.session_id == self.session_id).delete()
+        new = self.Session(session_id=self.session_id, dc_id=self._dc_id,
+                           server_address=self._server_address,
+                           port=self._port,
+                           auth_key=(self._auth_key.key
+                                     if self._auth_key else b''))
+        self.db.merge(new)
+
+    def _db_query(self, dbclass, *args):
+        return dbclass.query.filter(dbclass.session_id == self.session_id,
+                                    *args)
+
+    def save(self):
+        self.container.save()
+
+    def close(self):
+        # Nothing to do here, connection is managed by AlchemySessionContainer.
+        pass
+
+    def delete(self):
+        self._db_query(self.Session).delete()
+        self._db_query(self.Entity).delete()
+        self._db_query(self.SentFile).delete()
+
+    def _entity_values_to_row(self, id, hash, username, phone, name):
+        return self.Entity(session_id=self.session_id, id=id, hash=hash,
+                           username=username, phone=phone, name=name)
+
+    def process_entities(self, tlo):
+        rows = self._entities_to_rows(tlo)
+        if not rows:
+            return
+
+        for row in rows:
+            self.db.merge(row)
+        self.save()
+
+    def get_entity_rows_by_phone(self, key):
+        row = self._db_query(self.Entity,
+                             self.Entity.phone == key).one_or_none()
+        return row.id, row.hash if row else None
+
+    def get_entity_rows_by_username(self, key):
+        row = self._db_query(self.Entity,
+                             self.Entity.username == key).one_or_none()
+        return row.id, row.hash if row else None
+
+    def get_entity_rows_by_name(self, key):
+        row = self._db_query(self.Entity,
+                             self.Entity.name == key).one_or_none()
+        return row.id, row.hash if row else None
+
+    def get_entity_rows_by_id(self, key):
+        row = self._db_query(self.Entity, self.Entity.id == key).one_or_none()
+        return row.id, row.hash if row else None
+
+    def get_file(self, md5_digest, file_size, cls):
+        row = self._db_query(self.SentFile,
+                             self.SentFile.md5_digest == md5_digest,
+                             self.SentFile.file_size == file_size,
+                             self.SentFile.type == _SentFileType.from_type(
+                                 cls).value).one_or_none()
+        return row.id, row.hash if row else None
+
+    def cache_file(self, md5_digest, file_size, instance):
+        if not isinstance(instance, (InputDocument, InputPhoto)):
+            raise TypeError('Cannot cache %s instance' % type(instance))
+
+        self.db.merge(
+            self.SentFile(session_id=self.session_id, md5_digest=md5_digest,
+                          type=_SentFileType.from_type(type(instance)).value,
+                          id=instance.id, hash=instance.access_hash))
+        self.save()

telethon/sessions/sqlite.py

@@ -1,20 +1,13 @@
 import json
 import os
-import platform
 import sqlite3
-import struct
-import time
 from base64 import b64decode
-from enum import Enum
 from os.path import isfile as file_exists
 from threading import Lock, RLock
 
-from . import utils
-from .crypto import AuthKey
-from .tl import TLObject
-from .tl.types import (
-    PeerUser, PeerChat, PeerChannel,
-    InputPeerUser, InputPeerChat, InputPeerChannel,
+from .memory import MemorySession, _SentFileType
+from ..crypto import AuthKey
+from ..tl.types import (
     InputPhoto, InputDocument
 )
 
@@ -22,21 +15,7 @@ EXTENSION = '.session'
 CURRENT_VERSION = 3  # database version
 
 
-class _SentFileType(Enum):
-    DOCUMENT = 0
-    PHOTO = 1
-
-    @staticmethod
-    def from_type(cls):
-        if cls == InputDocument:
-            return _SentFileType.DOCUMENT
-        elif cls == InputPhoto:
-            return _SentFileType.PHOTO
-        else:
-            raise ValueError('The cls must be either InputDocument/InputPhoto')
-
-
-class Session:
+class SQLiteSession(MemorySession):
     """This session contains the required information to login into your
        Telegram account. NEVER give the saved JSON file to anyone, since
        they would gain instant access to all your messages and contacts.
@@ -44,59 +23,27 @@ class Session:
        If you think the session has been compromised, close all the sessions
        through an official Telegram client to revoke the authorization.
     """
-    def __init__(self, session_id):
+
+    def __init__(self, session_id=None):
+        super().__init__()
         """session_user_id should either be a string or another Session.
            Note that if another session is given, only parameters like
            those required to init a connection will be copied.
         """
         # These values will NOT be saved
         self.filename = ':memory:'
+        self.save_entities = True
 
-        # For connection purposes
-        if isinstance(session_id, Session):
-            self.device_model = session_id.device_model
-            self.system_version = session_id.system_version
-            self.app_version = session_id.app_version
-            self.lang_code = session_id.lang_code
-            self.system_lang_code = session_id.system_lang_code
-            self.lang_pack = session_id.lang_pack
-            self.report_errors = session_id.report_errors
-            self.save_entities = session_id.save_entities
-            self.flood_sleep_threshold = session_id.flood_sleep_threshold
-        else:  # str / None
-            if session_id:
-                self.filename = session_id
-                if not self.filename.endswith(EXTENSION):
-                    self.filename += EXTENSION
-
-            system = platform.uname()
-            self.device_model = system.system or 'Unknown'
-            self.system_version = system.release or '1.0'
-            self.app_version = '1.0'  # '0' will provoke error
-            self.lang_code = 'en'
-            self.system_lang_code = self.lang_code
-            self.lang_pack = ''
-            self.report_errors = True
-            self.save_entities = True
-            self.flood_sleep_threshold = 60
-
-        self.id = struct.unpack('q', os.urandom(8))[0]
-        self._sequence = 0
-        self.time_offset = 0
-        self._last_msg_id = 0  # Long
-        self.salt = 0  # Long
+        if session_id:
+            self.filename = session_id
+            if not self.filename.endswith(EXTENSION):
+                self.filename += EXTENSION
 
         # Cross-thread safety
         self._seq_no_lock = Lock()
         self._msg_id_lock = Lock()
         self._db_lock = RLock()
 
-        # These values will be saved
-        self._dc_id = 0
-        self._server_address = None
-        self._port = None
-        self._auth_key = None
-
         # Migrating from .json -> SQL
         entities = self._check_migrate_json()
 
@@ -163,6 +110,11 @@ class Session:
             c.close()
             self.save()
 
+    def clone(self, to_instance=None):
+        cloned = super().clone(to_instance)
+        cloned.save_entities = self.save_entities
+        return cloned
+
     def _check_migrate_json(self):
         if file_exists(self.filename):
             try:
@@ -218,9 +170,7 @@ class Session:
     # Data from sessions should be kept as properties
     # not to fetch the database every time we need it
     def set_dc(self, dc_id, server_address, port):
-        self._dc_id = dc_id
-        self._server_address = server_address
-        self._port = port
+        super().set_dc(dc_id, server_address, port)
         self._update_session_table()
 
         # Fetch the auth_key corresponding to this data center
@@ -233,19 +183,7 @@ class Session:
             self._auth_key = None
         c.close()
 
-    @property
-    def server_address(self):
-        return self._server_address
-
-    @property
-    def port(self):
-        return self._port
-
-    @property
-    def auth_key(self):
-        return self._auth_key
-
-    @auth_key.setter
+    @MemorySession.auth_key.setter
     def auth_key(self, value):
         self._auth_key = value
         self._update_session_table()
@@ -298,53 +236,14 @@ class Session:
         except OSError:
             return False
 
-    @staticmethod
-    def list_sessions():
+    @classmethod
+    def list_sessions(cls):
         """Lists all the sessions of the users who have ever connected
            using this client and never logged out
         """
         return [os.path.splitext(os.path.basename(f))[0]
                 for f in os.listdir('.') if f.endswith(EXTENSION)]
 
-    def generate_sequence(self, content_related):
-        """Thread safe method to generates the next sequence number,
-           based on whether it was confirmed yet or not.
-
-           Note that if confirmed=True, the sequence number
-           will be increased by one too
-        """
-        with self._seq_no_lock:
-            if content_related:
-                result = self._sequence * 2 + 1
-                self._sequence += 1
-                return result
-            else:
-                return self._sequence * 2
-
-    def get_new_msg_id(self):
-        """Generates a new unique message ID based on the current
-           time (in ms) since epoch"""
-        # Refer to mtproto_plain_sender.py for the original method
-        now = time.time() + self.time_offset
-        nanoseconds = int((now - int(now)) * 1e+9)
-        # "message identifiers are divisible by 4"
-        new_msg_id = (int(now) << 32) | (nanoseconds << 2)
-
-        with self._msg_id_lock:
-            if self._last_msg_id >= new_msg_id:
-                new_msg_id = self._last_msg_id + 4
-
-            self._last_msg_id = new_msg_id
-
-        return new_msg_id
-
-    def update_time_offset(self, correct_msg_id):
-        """Updates the time offset based on a known correct message ID"""
-        now = int(time.time())
-        correct = correct_msg_id >> 32
-        self.time_offset = correct - now
-        self._last_msg_id = 0
-
     # Entity processing
 
     def process_entities(self, tlo):
@@ -356,49 +255,7 @@ class Session:
         if not self.save_entities:
             return
 
-        if not isinstance(tlo, TLObject) and utils.is_list_like(tlo):
-            # This may be a list of users already for instance
-            entities = tlo
-        else:
-            entities = []
-            if hasattr(tlo, 'chats') and utils.is_list_like(tlo.chats):
-                entities.extend(tlo.chats)
-            if hasattr(tlo, 'users') and utils.is_list_like(tlo.users):
-                entities.extend(tlo.users)
-            if not entities:
-                return
-
-        rows = []  # Rows to add (id, hash, username, phone, name)
-        for e in entities:
-            if not isinstance(e, TLObject):
-                continue
-            try:
-                p = utils.get_input_peer(e, allow_self=False)
-                marked_id = utils.get_peer_id(p)
-            except ValueError:
-                continue
-
-            if isinstance(p, (InputPeerUser, InputPeerChannel)):
-                if not p.access_hash:
-                    # Some users and channels seem to be returned without
-                    # an 'access_hash', meaning Telegram doesn't want you
-                    # to access them. This is the reason behind ensuring
-                    # that the 'access_hash' is non-zero. See issue #354.
-                    # Note that this checks for zero or None, see #392.
-                    continue
-                else:
-                    p_hash = p.access_hash
-            elif isinstance(p, InputPeerChat):
-                p_hash = 0
-            else:
-                continue
-
-            username = getattr(e, 'username', None) or None
-            if username is not None:
-                username = username.lower()
-            phone = getattr(e, 'phone', None)
-            name = utils.get_display_name(e) or None
-            rows.append((marked_id, p_hash, username, phone, name))
+        rows = self._entities_to_rows(tlo)
         if not rows:
             return
 
@@ -408,62 +265,29 @@ class Session:
             )
             self.save()
 
-    def get_input_entity(self, key):
-        """Parses the given string, integer or TLObject key into a
-           marked entity ID, which is then used to fetch the hash
-           from the database.
-
-           If a callable key is given, every row will be fetched,
-           and passed as a tuple to a function, that should return
-           a true-like value when the desired row is found.
-
-           Raises ValueError if it cannot be found.
-        """
-        try:
-            if key.SUBCLASS_OF_ID in (0xc91c90b6, 0xe669bf46, 0x40f202fd):
-                # hex(crc32(b'InputPeer', b'InputUser' and b'InputChannel'))
-                # We already have an Input version, so nothing else required
-                return key
-            # Try to early return if this key can be casted as input peer
-            return utils.get_input_peer(key)
-        except (AttributeError, TypeError):
-            # Not a TLObject or can't be cast into InputPeer
-            if isinstance(key, TLObject):
-                key = utils.get_peer_id(key)
-
+    def _fetchone_entity(self, query, args):
         c = self._cursor()
-        if isinstance(key, str):
-            phone = utils.parse_phone(key)
-            if phone:
-                c.execute('select id, hash from entities where phone=?',
-                          (phone,))
-            else:
-                username, _ = utils.parse_username(key)
-                if username:
-                    c.execute('select id, hash from entities where username=?',
-                              (username,))
+        c.execute(query, args)
+        return c.fetchone()
 
-        if isinstance(key, int):
-            c.execute('select id, hash from entities where id=?', (key,))
+    def get_entity_rows_by_phone(self, phone):
+        return self._fetchone_entity(
+            'select id, hash from entities where phone=?', (phone,))
 
-        result = c.fetchone()
-        if not result and isinstance(key, str):
-            # Try exact match by name if phone/username failed
-            c.execute('select id, hash from entities where name=?', (key,))
-            result = c.fetchone()
+    def get_entity_rows_by_username(self, username):
+        return self._fetchone_entity(
+            'select id, hash from entities where username=?',
+            (username,))
 
-        c.close()
-        if result:
-            i, h = result  # unpack resulting tuple
-            i, k = utils.resolve_id(i)  # removes the mark and returns kind
-            if k == PeerUser:
-                return InputPeerUser(i, h)
-            elif k == PeerChat:
-                return InputPeerChat(i)
-            elif k == PeerChannel:
-                return InputPeerChannel(i, h)
-        else:
-            raise ValueError('Could not find input entity with key ', key)
+    def get_entity_rows_by_name(self, name):
+        return self._fetchone_entity(
+            'select id, hash from entities where name=?',
+            (name,))
+
+    def get_entity_rows_by_id(self, id):
+        return self._fetchone_entity(
+            'select id, hash from entities where id=?',
+            (id,))
 
     # File processing
 

telethon/telegram_bare_client.py

@@ -1,11 +1,11 @@
 import logging
 import os
+import platform
 import threading
 from datetime import timedelta, datetime
 from signal import signal, SIGINT, SIGTERM, SIGABRT
 from threading import Lock
 from time import sleep
-
 from . import version, utils
 from .crypto import rsa
 from .errors import (
@@ -14,7 +14,7 @@ from .errors import (
     PhoneMigrateError, NetworkMigrateError, UserMigrateError
 )
 from .network import authenticator, MtProtoSender, Connection, ConnectionMode
-from .session import Session
+from .sessions import Session, SQLiteSession
 from .tl import TLObject
 from .tl.all_tlobjects import LAYER
 from .tl.functions import (
@@ -73,7 +73,12 @@ class TelegramBareClient:
                  update_workers=None,
                  spawn_read_thread=False,
                  timeout=timedelta(seconds=5),
-                 **kwargs):
+                 loop=None,
+                 device_model=None,
+                 system_version=None,
+                 app_version=None,
+                 lang_code='en',
+                 system_lang_code='en'):
         """Refer to TelegramClient.__init__ for docs on this method"""
         if not api_id or not api_hash:
             raise ValueError(
@@ -81,10 +86,10 @@ class TelegramBareClient:
                 "Refer to telethon.rtfd.io for more information.")
 
         self._use_ipv6 = use_ipv6
-        
+
         # Determine what session object we have
         if isinstance(session, str) or session is None:
-            session = Session(session)
+            session = SQLiteSession(session)
         elif not isinstance(session, Session):
             raise TypeError(
                 'The given session must be a str or a Session instance.'
@@ -125,11 +130,12 @@ class TelegramBareClient:
         self.updates = UpdateState(workers=update_workers)
 
         # Used on connection - the user may modify these and reconnect
-        kwargs['app_version'] = kwargs.get('app_version', self.__version__)
-        for name, value in kwargs.items():
-            if not hasattr(self.session, name):
-                raise ValueError('Unknown named parameter', name)
-            setattr(self.session, name, value)
+        system = platform.uname()
+        self.device_model = device_model or system.system or 'Unknown'
+        self.system_version = system_version or system.release or '1.0'
+        self.app_version = app_version or self.__version__
+        self.lang_code = lang_code
+        self.system_lang_code = system_lang_code
 
         # Despite the state of the real connection, keep track of whether
         # the user has explicitly called .connect() or .disconnect() here.
@@ -233,11 +239,11 @@ class TelegramBareClient:
         """Wraps query around InvokeWithLayerRequest(InitConnectionRequest())"""
         return InvokeWithLayerRequest(LAYER, InitConnectionRequest(
             api_id=self.api_id,
-            device_model=self.session.device_model,
-            system_version=self.session.system_version,
-            app_version=self.session.app_version,
-            lang_code=self.session.lang_code,
-            system_lang_code=self.session.system_lang_code,
+            device_model=self.device_model,
+            system_version=self.system_version,
+            app_version=self.app_version,
+            lang_code=self.lang_code,
+            system_lang_code=self.system_lang_code,
             lang_pack='',  # "langPacks are for official apps only"
             query=query
         ))
@@ -361,7 +367,7 @@ class TelegramBareClient:
             #
             # Construct this session with the connection parameters
             # (system version, device model...) from the current one.
-            session = Session(self.session)
+            session = self.session.clone()
             session.set_dc(dc.id, dc.ip_address, dc.port)
             self._exported_sessions[dc_id] = session
 
@@ -387,7 +393,7 @@ class TelegramBareClient:
         session = self._exported_sessions.get(cdn_redirect.dc_id)
         if not session:
             dc = self._get_dc(cdn_redirect.dc_id, cdn=True)
-            session = Session(self.session)
+            session = self.session.clone()
             session.set_dc(dc.id, dc.ip_address, dc.port)
             self._exported_sessions[cdn_redirect.dc_id] = session