[CI/Build] Unpin outlines

[br3no]

Unpin the outlines dependency.

FIX #4153

Since work on #4109 will take a bit longer...

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[simon-mo]

I think the reason for the pin is exactly the error here in test...

_________ ERROR collecting tests/entrypoints/test_guided_processors.py _________
--
  | ImportError while importing test module '/vllm-workspace/tests/entrypoints/test_guided_processors.py'.
  | Hint: make sure your test modules/packages have valid Python names.
  | Traceback:
  | /usr/lib/python3.10/importlib/__init__.py:126: in import_module
  | return _bootstrap._gcd_import(name[level:], package, level)
  | entrypoints/test_guided_processors.py:8: in <module>
  | from vllm.model_executor.guided_decoding import (
  | /usr/local/lib/python3.10/dist-packages/vllm/model_executor/guided_decoding/__init__.py:5: in <module>
  | from vllm.model_executor.guided_decoding.lm_format_enforcer_decoding import (
  | /usr/local/lib/python3.10/dist-packages/vllm/model_executor/guided_decoding/lm_format_enforcer_decoding.py:15: in <module>
  | from vllm.model_executor.guided_decoding.outlines_decoding import (
  | /usr/local/lib/python3.10/dist-packages/vllm/model_executor/guided_decoding/outlines_decoding.py:15: in <module>
  | from vllm.model_executor.guided_decoding.outlines_logits_processors import (
  | /usr/local/lib/python3.10/dist-packages/vllm/model_executor/guided_decoding/outlines_logits_processors.py:24: in <module>
  | from outlines.fsm.fsm import CFGFSM, FSM, RegexFSM
  | E   ImportError: cannot import name 'FSM' from 'outlines.fsm.fsm' (/usr/local/lib/python3.10/dist-packages/outlines/fsm/fsm.py)

[br3no]

I have removed the FSM import that made this particular test fail.

The thing is that the underlying implementation is the same as with the Guide interface and the issue reported in outlines-dev/outlines#856 will break tests again.

I'm afraid we'll have to wait for this issue to be fixed.

I'm inclined to close this PR...

[saattrupdan]

I have removed the FSM import that made this particular test fail.

The thing is that the underlying implementation is the same as with the Guide interface and the issue reported in outlines-dev/outlines#856 will break tests again.

I'm afraid we'll have to wait for this issue to be fixed.

I'm inclined to close this PR...

There are several of us who are not using the vllm implementation of outlines, but we are merely using standard vllm with the JSONLogitsProcessor from outlines directly - this works perfectly fine. I don't really see why vllm needs its own "copy" of the outlines code, rather than just importing it? In any case, I would be perfectly happy if all imports from outlines in the vllm code could be packed away in a function, since that's what's blocking me right now.

[br3no]

It's up for the maintainers of vLLM to decide what exactly is to be done here.

We can:

1. wait for Endless generation bug popped up during migration to Guide in vLLM integration outlines-dev/outlines#856 to be fixed and only then unpin outlines
2. unpin outlines and disable the failing test (this is a regression) and re-enable the test once the issue above is fixed
3. make the dependency of outlines optional (@saattrupdan if you feel strongly about this, then I would recommend you open a PR for it...)

[simon-mo]

I don't really see why vllm needs its own "copy" of the outlines code, rather than just importing it?

This is recommended by the outlines maintainers for us to maintain the logits processor interface and keep the interface between libraries at the FSM/Guide level.

[simon-mo]

Hmmm. It's generating '3.5.0.10653515246264', maybe tune the temperature or prompting?
https://buildkite.com/vllm/ci/builds/6481#018f3d50-d8eb-4258-8260-ef486c1466ca/51-578

[br3no]

@simon-mo that’s the regression described in outlines-dev/outlines#856. This is a bug in outlines.

We can either disable the test, or wait for the fix, as I listed above.

[br3no]

I have identified the source of the problem in outlines and am waiting for a PR (outlines-dev/outlines#874) to get merged with the fix. Once this is done, we can move on with the migration to the Guide API.

I'll close this PR in favor of #4109.

[rlouf]

I merged the PR that fixes outlines-dev/outlines#874. Indeed @saattrupdan I think it makes more sense to have the processors in vLLM so Outlines is not concerned with details of the implementation and can focus on structured generation alone.

[saattrupdan]

Indeed @saattrupdan I think it makes more sense to have the processors in vLLM so Outlines is not concerned with details of the implementation and can focus on structured generation alone.

Ah, so the plan is to remove the vLLM integration from the outlines code, and instead ask users to use the one in vLLM?