fix(job): use Optional for parameters defaulting to None [python] - #4908

Port Impact Checklist

• Python – does this change need to be ported or documented in the Python library?
• Elixir – does this change need to be ported or documented in the Elixir library?
• PHP – does this change need to be ported or documented in the PHP library?
• Rust – does this change need to be ported or documented in the Rust library?
• .NET – does this change need to be ported or documented in the .NET library?

Why

Parameters annotated str (or dict/Redis) but defaulting to None are implicit Optional, which PEP 484 and the current typing spec prohibit. When bullmq is used as an external package, type checkers therefore pick job_id: str and hide that None is accepted, so Job(queue, name, data, job_id=None) is reported as an error and Job.id is typed str.

Fixes #4905

How

Annotated these as Optional[...], matching the style already used in the package (e.g. Optional[str] = None in redis_connection.py):

• Job.__init__(job_id) and Job.token
• Queue.upsertJobScheduler(job_name, opts, producer_id)
• Scripts.addJobScheduler and Scripts.updateJobSchedulerNextMillis (producer_id)
• Scripts.extendLock(client)

An AST scan of python/bullmq finds no remaining implicit-Optional parameters.

Additional Notes (Optional)

• Annotations only; no runtime behaviour change apart from the added Optional import.
• Checked with a consumer script type-checked by mypy: before, Job(..., job_id=None) and upsertJobScheduler(job_name=None, opts=None, producer_id=None) produced 4 errors and Job.id was str; after, 0 errors and Job.id is str | None.
• Side effect: Job.id is now honestly Optional[str], so mypy --no-implicit-optional reports a few new "str | None passed where str expected" errors where id is forwarded (e.g. scripts.toKey, moveToFinished, LockManager.track_job). These were latent before; CI installs mypy but does not run it. Happy to follow up with narrowing there if wanted.
• I could not run the pytest suite locally (no Redis available); relying on CI for that. The flake8 gate (E9,F63,F7,F82) passes and the changed files compile.
• Tooling: written with the help of an AI assistant (Claude Code); I reviewed the diff.

🤖 Generated with Claude Code