René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Bug: Error when running multi-processing populate with tls=False","articleBody":"## Bug Report\n\n### Description\nWhen running  a populate of a table with dj.config.database.use_tls = False, when multiprocessing (e.g. processes=5) it fails. Works with use_tls = True.\n\n### Reproducibility\nminimal example\n\n```\nimport datajoint as dj\ndj.config.database.use_tls = False\ndj.conn() # using datajoint.json\nschema = dj.Schema(\"TEST\")\n\n@schema\nclass Numbers(dj.Lookup):\n    definition = \"\"\"\n    number: int64\n    \"\"\"\n    contents = [(0,), (1,), (2,), (4,), (8,)]\n\n@schema\nclass NumbersSquared(dj.Computed):\n    definition = \"\"\"\n    -\u003e Numbers\n    ---\n    squared: int64\n    \"\"\"\n\n    def make(self, key):\n        self.insert1({**key, \"squared\": key[\"number\"] ** 2})\nNumbersSquared.populate(suppress_errors=True, reserve_jobs=True, processes=5)\n```\n\n\n\nfails with \n```\n---------------------------------------------------------------------------\nAttributeError                            Traceback (most recent call last)\nCell In[1], line 23\n     21     def make(self, key):\n     22         self.insert1({**key, \"squared\": key[\"number\"] ** 2})\n---\u003e 23 NumbersSquared.populate(suppress_errors=True, reserve_jobs=True, processes=5)\n\nFile ~/datajoint-python/src/datajoint/autopopulate.py:366, in AutoPopulate.populate(self, suppress_errors, return_exception_objects, reserve_jobs, max_calls, display_progress, processes, make_kwargs, priority, refresh, *restrictions)\n    363     raise DataJointError(\"Populate cannot be called during a transaction.\")\n    365 if reserve_jobs:\n--\u003e 366     return self._populate_distributed(\n    367         *restrictions,\n    368         suppress_errors=suppress_errors,\n    369         return_exception_objects=return_exception_objects,\n    370         max_calls=max_calls,\n    371         display_progress=display_progress,\n    372         processes=processes,\n    373         make_kwargs=make_kwargs,\n    374         priority=priority,\n    375         refresh=refresh,\n    376     )\n    377 else:\n    378     return self._populate_direct(\n    379         *restrictions,\n    380         suppress_errors=suppress_errors,\n   (...)    385         make_kwargs=make_kwargs,\n    386     )\n\nFile ~/datajoint-python/src/datajoint/autopopulate.py:525, in AutoPopulate._populate_distributed(self, suppress_errors, return_exception_objects, max_calls, display_progress, processes, make_kwargs, priority, refresh, *restrictions)\n    521         # status is False means job was already reserved\n    522 else:\n    523     # spawn multiple processes\n    524     self.connection.close()\n--\u003e 525     del self.connection._conn.ctx  # SSLContext is not pickleable\n    526     with (\n    527         mp.Pool(processes, _initialize_populate, (self, self.jobs, populate_kwargs)) as pool,\n    528         tqdm(desc=\"Processes: \", total=nkeys)\n    529         if display_progress\n    530         else contextlib.nullcontext() as progress_bar,\n    531     ):\n    532         for status in pool.imap(_call_populate1, keys, chunksize=1):\n\nAttributeError: 'Connection' object has no attribute 'ctx'\n```\n\nUbuntu 24.04, python 3.12.11\nMySQL - remotely accessed myslq-latest docker (MySQL Server 9.6.0-1.el9)\nDataJoint Version : DataJoint 2.0.0a27\n\n### Expected Behavior\nDelete ctx only if it  exist\n\n\n```\nif getattr(self.connection._conn, 'ctx', False):\n    del self.connection._conn.ctx\n```\n\n\n","author":{"url":"https://github.com/arturoptophys","@type":"Person","name":"arturoptophys"},"datePublished":"2026-02-03T17:18:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/1374/datajoint-python/issues/1374"}