Log Received Data on Deserialization Errors (#4304)

telegram/_bot.py

@@ -4374,7 +4374,16 @@ class Bot(TelegramObject, AsyncContextManager["Bot"]):
         else:
             self._LOGGER.debug("No new updates found.")
 
+        try:
             return Update.de_list(result, self)
+        except Exception as exc:
+            # This logging is in place mostly b/c we can't access the raw json data in Updater,
+            # where the exception is caught and logged again. Still, it might also be beneficial
+            # for custom usages of `get_updates`.
+            self._LOGGER.critical(
+                "Error while parsing updates! Received data was %r", result, exc_info=exc
+            )
+            raise exc
 
     async def set_webhook(
         self,

telegram/ext/_utils/webhookhandler.py

@@ -168,7 +168,8 @@ class TelegramHandler(tornado.web.RequestHandler):
         except Exception as exc:
             _LOGGER.critical(
                 "Something went wrong processing the data received from Telegram. "
-                "Received data was *not* processed!",
+                "Received data was *not* processed! Received data was: %r",
+                data,
                 exc_info=exc,
             )
             raise tornado.web.HTTPError(

tests/ext/test_updater.py

@@ -1179,6 +1179,7 @@ class TestUpdater:
 
             assert len(caplog.records) == 1
             assert caplog.records[-1].getMessage().startswith("Something went wrong processing")
+            assert "Received data was: {" in caplog.records[-1].getMessage()
             assert caplog.records[-1].name == "telegram.ext.Updater"
             assert response.status_code == 400
             assert response.text == self.response_text.format(

tests/test_bot.py

@@ -535,6 +535,29 @@ class TestBotWithoutRequest:
             123, "text", api_kwargs={"unknown_kwarg_1": 7, "unknown_kwarg_2": 5}
         )
 
+    async def test_get_updates_deserialization_error(self, bot, monkeypatch, caplog):
+        async def faulty_do_request(*args, **kwargs):
+            return (
+                HTTPStatus.OK,
+                b'{"ok": true, "result": [{"update_id": "1", "message": "unknown_format"}]}',
+            )
+
+        monkeypatch.setattr(HTTPXRequest, "do_request", faulty_do_request)
+
+        bot = PytestExtBot(get_updates_request=HTTPXRequest(), token=bot.token)
+
+        with caplog.at_level(logging.CRITICAL), pytest.raises(AttributeError):
+            await bot.get_updates()
+
+        assert len(caplog.records) == 1
+        assert caplog.records[0].name == "telegram.ext.ExtBot"
+        assert caplog.records[0].levelno == logging.CRITICAL
+        assert caplog.records[0].getMessage() == (
+            "Error while parsing updates! Received data was "
+            "[{'update_id': '1', 'message': 'unknown_format'}]"
+        )
+        assert caplog.records[0].exc_info[0] is AttributeError
+
     async def test_answer_web_app_query(self, bot, raw_bot, monkeypatch):
         params = False