Fixes #7406 UnicodeDecodeError in on_tracker_error_alert

src/tribler/core/components/libtorrent/download_manager/download.py

@@ -312,12 +312,12 @@ def on_tracker_reply_alert(self, alert: lt.tracker_reply_alert):
         self.tracker_status[alert.url] = [alert.num_peers, 'Working']
 
     def on_tracker_error_alert(self, alert: lt.tracker_error_alert):
-        self._logger.error(f'On tracker error alert: {alert}')
-
-        # try-except block here is a workaround and has been added to solve
-        # the issue: "UnicodeDecodeError: invalid continuation byte"
+        # The try-except block is added as a workaround to suppress UnicodeDecodeError in `repr(alert)`,
+        # `alert.url` and `alert.msg`. See https://github.com/arvidn/libtorrent/issues/143
         try:
+            self._logger.error(f'On tracker error alert: {alert}')
             url = alert.url
+
             peers = self.tracker_status[url][0] if url in self.tracker_status else 0
             if alert.msg:
                 status = 'Error: ' + alert.msg
@@ -330,8 +330,7 @@ def on_tracker_error_alert(self, alert: lt.tracker_error_alert):
 
             self.tracker_status[url] = [peers, status]
         except UnicodeDecodeError as e:
-            self._logger.exception(e)
-            return
+            self._logger.warning(f'UnicodeDecodeError in on_tracker_error_alert: {e}')
 
     def on_tracker_warning_alert(self, alert: lt.tracker_warning_alert):
         self._logger.warning(f'On tracker warning alert: {alert}')

src/tribler/core/components/libtorrent/tests/test_download.py

@@ -4,6 +4,7 @@
 
 import libtorrent as lt
 import pytest
+from _pytest.logging import LogCaptureFixture
 from ipv8.util import succeed
 from libtorrent import bencode
 
@@ -238,6 +239,14 @@ def test_process_error_alert(test_download):
     assert test_download.tracker_status[url][1] == 'Timeout'
 
 
+def test_tracker_error_alert_unicode_decode_error(test_download: Download, caplog: LogCaptureFixture):
+    exception = UnicodeDecodeError('utf-8', b'\xc3\x28', 0, 1, 'invalid continuation byte')
+    mock_alert = MagicMock(__repr__=Mock(side_effect=exception))
+    test_download.process_alert(mock_alert, 'tracker_error_alert')
+    assert caplog.messages == ["UnicodeDecodeError in on_tracker_error_alert: "
+                               "'utf-8' codec can't decode byte 0xc3 in position 0: invalid continuation byte"]
+
+
 def test_tracker_warning_alert(test_download):
     """
     Test whether a tracking warning alert is processed correctly