cyclic object references aren't checked, leads to RecursionError

[gabroo]

Thanks for stopping by to let us know something could be better!

PLEASE READ: If you have a support contract with Google, please create an issue in the support console instead of filing on GitHub. This will ensure a timely response.

Please run down the following list and make sure you've tried the usual "quick fixes":

• Search the issues already opened: https://github.com/googleapis/python-logging/issues
• Search StackOverflow: https://stackoverflow.com/questions/tagged/google-cloud-platform+python

If you are still having issues, please be sure to include as much information as possible:

Environment details

• OS type and version: macOS 12.2.1
• Python version: python --version 3.8.12
• pip version: pip --version 21.2.4
• google-cloud-logging version: pip show google-cloud-logging 3.0.0

Steps to reproduce

1. pip install google-cloud-logging==3.0.0

Code example

from google.cloud.logging import Client
c = Client()
a = {"foo": "bar"}
a["baz"] = a
c.logger("logs").log(a)

Stack trace

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/cloud/logging_v2/logger.py", line 245, in log
    self.log_struct(message, client=client, **kw)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/cloud/logging_v2/logger.py", line 209, in log_struct
    self._do_log(client, StructEntry, info, **kw)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/cloud/logging_v2/logger.py", line 158, in _do_log
    client.logging_api.write_entries([api_repr])
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/cloud/logging_v2/_gapic.py", line 151, in write_entries
    log_entry_pbs = [_log_entry_mapping_to_pb(entry) for entry in entries]
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/cloud/logging_v2/_gapic.py", line 151, in <listcomp>
    log_entry_pbs = [_log_entry_mapping_to_pb(entry) for entry in entries]
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/cloud/logging_v2/_gapic.py", line 542, in _log_entry_mapping_to_pb
    ParseDict(mapping, entry_pb)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 445, in ParseDict
    parser.ConvertMessage(js_dict, message)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 476, in ConvertMessage
    self._ConvertFieldValuePair(value, message)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 580, in _ConvertFieldValuePair
    self.ConvertMessage(value, sub_message)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 474, in ConvertMessage
    methodcaller(_WKTJSONMETHODS[full_name][1], value, message)(self)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 666, in _ConvertStructMessage
    self._ConvertValueMessage(value[key], message.fields[key])
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 633, in _ConvertValueMessage
    self._ConvertStructMessage(value, message.struct_value)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 666, in _ConvertStructMessage
    self._ConvertValueMessage(value[key], message.fields[key])
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 633, in _ConvertValueMessage
    self._ConvertStructMessage(value, message.struct_value)
  File "/usr/local/google/home/sajeevs/miniconda3/envs/test/lib/python3.8/site-packages/google/protobuf/json_format.py", line 666, in _ConvertStructMessage
    self._ConvertValueMessage(value[key], message.fields[key])

[...]

RecursionError: maximum recursion depth exceeded while calling a Python object

Making sure to follow these steps will guarantee the quickest resolution possible.

Thanks!

[arbrown]

It looks like this is a known issue with the protobuf serialization format used to send log entries to the API. The only surefire solution I can think of would involve rewriting the serialization to do this check for us, and the issue I linked above implies there is little chance of that.

If you need to log such a relationship, you might consider doing so with ids instead of object references:

from google.cloud.logging import Client
c = Client()
a = {"foo": "bar", id: 7}
a["baz_id"] = a.id
c.logger("logs").log(a)

I will close this issue next week, but please let me know if there is a pressing need to log these kinds of cyclic relationships and we can consider looking into it further.

[gabroo]

Thanks for looking into it. I didn't look close enough to realize it's a protobuf error. We have no need to log these types of structs but it was something that popped up when writing tests.