René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"3.12.4 breaks`logging.config.DictConfig` with `logging.handlers.QueueHandler`  on read-only file systems","articleBody":"# Bug report\r\n\r\n### Bug description:\r\n\r\nWhen using `logging.config.dictConfig` to configure a `logging.handlers.QueueHandler` on a read only file system, it works fine in 3.12.3, but crashes in 3.12.4.\r\n\r\n**Reproducing**\r\n\r\n```python\r\n# bug.py\r\nimport logging.config\r\n\r\nlogging.config.dictConfig(\r\n    {\r\n        \"version\": 1,\r\n        \"handlers\": {\r\n            \"queue_listener\": {\r\n                \"class\": \"logging.handlers.QueueHandler\",\r\n                \"queue\": {\"()\": \"queue.Queue\", \"maxsize\": -1},\r\n            },\r\n        },\r\n    }\r\n)\r\n```\r\n\r\n```dockerfile\r\n# Dockerfile\r\nFROM python:3.12.4-slim-bookworm\r\n\r\nCOPY bug.py ./\r\n\r\nCMD [\"python\", \"bug.py\"]\r\n```\r\n\r\nRun `docker run --rm --read-only -it $(docker build -q .)`\r\n\r\n```\r\nProcess SyncManager-1:\r\nTraceback (most recent call last):\r\n  File \"/usr/local/lib/python3.12/multiprocessing/process.py\", line 314, in _bootstrap\r\n    self.run()\r\n  File \"/usr/local/lib/python3.12/multiprocessing/process.py\", line 108, in run\r\n    self._target(*self._args, **self._kwargs)\r\n  File \"/usr/local/lib/python3.12/multiprocessing/managers.py\", line 591, in _run_server\r\n    server = cls._Server(registry, address, authkey, serializer)\r\n             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/managers.py\", line 156, in __init__\r\n    self.listener = Listener(address=address, backlog=128)\r\n                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/connection.py\", line 458, in __init__\r\n    address = address or arbitrary_address(family)\r\n                         ^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/connection.py\", line 77, in arbitrary_address\r\n    return tempfile.mktemp(prefix='listener-', dir=util.get_temp_dir())\r\n                                                   ^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/util.py\", line 149, in get_temp_dir\r\n    tempdir = tempfile.mkdtemp(prefix='pymp-')\r\n              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/tempfile.py\", line 373, in mkdtemp\r\n    prefix, suffix, dir, output_type = _sanitize_params(prefix, suffix, dir)\r\n                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/tempfile.py\", line 126, in _sanitize_params\r\n    dir = gettempdir()\r\n          ^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/tempfile.py\", line 315, in gettempdir\r\n    return _os.fsdecode(_gettempdir())\r\n                        ^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/tempfile.py\", line 308, in _gettempdir\r\n    tempdir = _get_default_tempdir()\r\n              ^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/tempfile.py\", line 223, in _get_default_tempdir\r\n    raise FileNotFoundError(_errno.ENOENT,\r\nFileNotFoundError: [Errno 2] No usable temporary directory found in ['/tmp', '/var/tmp', '/usr/tmp', '/']\r\nTraceback (most recent call last):\r\n  File \"/usr/local/lib/python3.12/logging/config.py\", line 581, in configure\r\n    handler = self.configure_handler(handlers[name])\r\n              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/logging/config.py\", line 792, in configure_handler\r\n    proxy_queue = MM().Queue()\r\n                  ^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/context.py\", line 57, in Manager\r\n    m.start()\r\n  File \"/usr/local/lib/python3.12/multiprocessing/managers.py\", line 566, in start\r\n    self._address = reader.recv()\r\n                    ^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/connection.py\", line 250, in recv\r\n    buf = self._recv_bytes()\r\n          ^^^^^^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/connection.py\", line 430, in _recv_bytes\r\n    buf = self._recv(4)\r\n          ^^^^^^^^^^^^^\r\n  File \"/usr/local/lib/python3.12/multiprocessing/connection.py\", line 399, in _recv\r\n    raise EOFError\r\nEOFError\r\n\r\nThe above exception was the direct cause of the following exception:\r\n\r\nTraceback (most recent call last):\r\n  File \"//bug.py\", line 3, in \u003cmodule\u003e\r\n    logging.config.dictConfig(\r\n  File \"/usr/local/lib/python3.12/logging/config.py\", line 920, in dictConfig\r\n    dictConfigClass(config).configure()\r\n  File \"/usr/local/lib/python3.12/logging/config.py\", line 588, in configure\r\n    raise ValueError('Unable to configure handler '\r\nValueError: Unable to configure handler 'queue_listener'\r\n```\r\n\r\n\u003chr\u003e\r\n\r\nFrom my understanding, this is related to #119819 et al. and the change that caused this was introduced in #120030: It introduces creating ephemeral instances of `multiprocessing.Manager` which, on init, tries to acquire a temporary directory. \r\n\r\nhttps://github.com/python/cpython/blob/879d1f28bb97bcecddca0824276877aaf97f25b3/Lib/logging/config.py#L785\r\n\r\n\r\n\r\n\r\n### CPython versions tested on:\r\n\r\n3.12\r\n\r\n### Operating systems tested on:\r\n\r\nLinux\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-120872\n* gh-121077\n* gh-121078\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/provinzkraut","@type":"Person","name":"provinzkraut"},"datePublished":"2024-06-22T08:52:54.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/120868/cpython/issues/120868"}