Fix errors when users absent from the database use bot

As a consequence of losing data and loading an older dump we lost some
of our users as well, so when they trigger some of the handlers which
assume that user already is in the database, because bot adds them on
/start, it raises various exceptions.

This is a hack which solves the problem by replacing whatever user was
doing with the /start command as if user is new.

Signed-off-by: alfred richardsn <rchrdsn@protonmail.ch>

src/bot.py

@@ -17,6 +17,7 @@
 import asyncio
 import logging
 import typing
+from time import time
 
 from aiogram import Bot
 from aiogram import types
@@ -27,6 +28,7 @@
 
 from src.config import config
 from src.database import database
+from src.database import database_user
 from src.database import MongoStorage
 from src.i18n import i18n
 
@@ -81,8 +83,44 @@ async def request(self, method, data=None, *args, **kwargs):
         return result
 
 
+class DispatcherManual(Dispatcher):
+    """Dispatcher with user availability in database check."""
+
+    async def process_update(self, update: types.Update):
+        """Process update object with user availability in database check.
+
+        If bot doesn't know the user, it pretends they sent /start message.
+        """
+        user = None
+        if update.message:
+            user = update.message.from_user
+            chat = update.message.chat
+        elif update.callback_query and update.callback_query.message:
+            user = update.callback_query.from_user
+            chat = update.callback_query.message.chat
+        if user:
+            db_user = await database.users.find_one({"id": user.id, "chat": chat.id})
+            if db_user is None:
+                if update.message:
+                    update.message.text = "/start"
+                elif update.callback_query:
+                    update = types.Update(
+                        update_id=update.update_id,
+                        message={
+                            "message_id": -1,
+                            "from": user.to_python(),
+                            "chat": chat.to_python(),
+                            "date": int(time()),
+                            "text": "/start",
+                        },
+                    )
+                    await update.callback_query.answer()
+            database_user.set(db_user)
+        return await super().process_update(update)
+
+
 tg = TellerBot(None, loop=asyncio.get_event_loop(), validate_token=False)
-dp = Dispatcher(tg)
+dp = DispatcherManual(tg)
 
 
 def setup():

src/database.py

@@ -15,6 +15,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with TellerBot.  If not, see <https://www.gnu.org/licenses/>.
 import typing
+from contextvars import ContextVar
 
 from aiogram.dispatcher.storage import BaseStorage
 from motor.motor_asyncio import AsyncIOMotorClient
@@ -34,6 +35,8 @@
     client = AsyncIOMotorClient(config.DATABASE_HOST)
 database = client[config.DATABASE_NAME]
 
+database_user: ContextVar[typing.Mapping[str, typing.Any]] = ContextVar("database_user")
+
 STATE_KEY = "state"
 
 

src/handlers/base.py

@@ -35,7 +35,7 @@
     state_handlers,
 )
 from src.bot import tg
-from src.database import database, STATE_KEY
+from src.database import database, database_user, STATE_KEY
 from src.i18n import i18n
 from src.money import normalize
 
@@ -102,7 +102,7 @@ async def orders_list(
     :param message_id: Telegram ID of message to edit.
     :param invert: Invert all prices.
     """
-    user = await database.users.find_one({"id": types.User.get_current().id})
+    user = database_user.get()
     if invert is None:
         invert = user.get("invert_book", False)
     else:
@@ -116,13 +116,13 @@ async def orders_list(
         types.InlineKeyboardButton(
             emojize(":arrow_left:"),
             callback_data="{} {} {}".format(
-                buttons_data, start - config.ORDERS_COUNT, int(invert)
+                buttons_data, start - config.ORDERS_COUNT, 1 if invert else 0
             ),
         ),
         types.InlineKeyboardButton(
             emojize(":arrow_right:"),
             callback_data="{} {} {}".format(
-                buttons_data, start + config.ORDERS_COUNT, int(invert)
+                buttons_data, start + config.ORDERS_COUNT, 1 if invert else 0
             ),
         ),
     )
@@ -252,7 +252,7 @@ async def show_order(
 
     new_edit_msg = None
     if invert is None:
-        user = await database.users.find_one({"id": user_id})
+        user = database_user.get()
         invert = user.get("invert_order", False)
     else:
         user = await database.users.find_one_and_update(

src/handlers/order.py

@@ -36,6 +36,7 @@
 from src.bot import tg
 from src.config import config
 from src.database import database
+from src.database import database_user
 from src.database import STATE_KEY
 from src.escrow import get_escrow_instance
 from src.escrow.escrow_offer import EscrowOffer
@@ -344,13 +345,16 @@ async def escrow_button(call: types.CallbackQuery, order: OrderType):
                 i18n("cancel"), callback_data=f"init_cancel {offer_id}"
             )
         )
-        projection = {"id": True, "locale": True, "mention": True}
         escrow_type = "buy" if get_escrow_instance(order["buy"]) else "sell"
-        init_user = await database.users.find_one(
-            {"id": call.from_user.id}, projection=projection
-        )
+        user = database_user.get()
+        init_user = {
+            "id": user["id"],
+            "locale": user["locale"],
+            "mention": user["mention"],
+        }
         counter_user = await database.users.find_one(
-            {"id": order["user_id"]}, projection=projection
+            {"id": order["user_id"]},
+            projection={"id": True, "locale": True, "mention": True},
         )
         await database.escrow.delete_many({"init.send_address": {"$exists": False}})
         offer = EscrowOffer(
@@ -399,7 +403,7 @@ async def edit_button(call: types.CallbackQuery):
         answer = i18n("send_new_sell_amount")
         keyboard.row(unset_button)
     elif field == "price":
-        user = await database.users.find_one({"id": call.from_user.id})
+        user = database_user.get()
         answer = i18n("new_price {of_currency} {per_currency}")
         if user.get("invert_order", False):
             answer = answer.format(of_currency=order["buy"], per_currency=order["sell"])
@@ -433,7 +437,7 @@ async def edit_button(call: types.CallbackQuery):
     if not answer:
         return
 
-    user = await database.users.find_one({"id": call.from_user.id})
+    user = database_user.get()
     if "edit" in user:
         await tg.delete_message(call.message.chat.id, user["edit"]["message_id"])
     result = await tg.send_message(call.message.chat.id, answer, reply_markup=keyboard,)
@@ -482,7 +486,7 @@ async def finish_edit(user, update_dict):
 )
 async def default_duration(call: types.CallbackQuery, state: FSMContext):
     """Repeat default duration."""
-    user = await database.users.find_one({"id": call.from_user.id})
+    user = database_user.get()
     order = await database.orders.find_one({"_id": user["edit"]["order_id"]})
     await call.answer()
     await finish_edit(
@@ -505,7 +509,7 @@ async def default_duration(call: types.CallbackQuery, state: FSMContext):
 )
 async def unset_button(call: types.CallbackQuery, state: FSMContext):
     """React to "Unset" button by unsetting the edit field."""
-    user = await database.users.find_one({"id": call.from_user.id})
+    user = database_user.get()
     field = user["edit"]["field"]
     if field == "price":
         unset_dict = {"price_buy": True, "price_sell": True}
@@ -522,7 +526,7 @@ async def unset_button(call: types.CallbackQuery, state: FSMContext):
 @private_handler(state=states.field_editing)
 async def edit_field(message: types.Message, state: FSMContext):
     """Ask new value of chosen order's field during editing."""
-    user = await database.users.find_one({"id": message.from_user.id})
+    user = database_user.get()
     edit = user["edit"]
     field = edit["field"]
     invert = user.get("invert_order", False)