Cannot import flux.resource

[jwhite242]

Checked this on a couple machines and virtualenviornments to ensure it wasn't a fluke. I am trying to import the resource list (https://flux-framework.readthedocs.io/projects/flux-core/en/stable/python/autogenerated/flux.resource.list.html) to do a little checking/logging on the instance I'm looking to submit some jobs to (also precursor to playing with hierarchical scheduling where i need to know the size to pick one). It returns a module not found error. Simple reproducer below:

In [7]: import flux.resource.list as frl
---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[7], line 1
----> 1 import flux.resource.list as frl

File /path/to/myvenv/lib/python3.11/site-packages/flux/resource/__init__.py:11
      1 ###############################################################
      2 # Copyright 2020 Lawrence Livermore National Security, LLC
      3 # (c.f. AUTHORS, NOTICE.LLNS, COPYING)
   (...)      8 # SPDX-License-Identifier: LGPL-3.0
      9 ###############################################################
---> 11 from flux.resource.Rlist import Rlist
     12 from flux.resource.ResourceSet import ResourceSet
     13 from flux.resource.list import resource_list, SchedResourceList

File /path/to/myvenv//lib/python3.11/site-packages/flux/resource/Rlist.py:15
     12 import socket
     13 from collections.abc import Mapping
---> 15 from _flux._rlist import ffi, lib
     16 from flux.hostlist import Hostlist
     17 from flux.idset import IDset

ModuleNotFoundError: No module named '_flux._rlist'

Note that i can successfully import flux and query brokers for their version (import flux, fh = Flux(), fh.attr_get...), so the bindings are installing ok, just missing something? Tried it on two of the El Cap prototypes in case that matters, one was at flux version 0.70.0, the other at 0.71.0 (no bindings for the latter, but same error so not the cause).

[vsoch]

Please test / compare with the system flux, and look for differences. First, if the system level flux import doesn't work, the issue is there. If there is a difference in the install structure, then we likely need an update to the logic. Let me know what you find.

[jwhite242]

If you mean test this outside of an allocation, that does fail too with the same import error. Apologies for omitting the details of what broker/instance I tested against.

edit: happy to test other python versions as well too; just using the default selection in the lmod setup on the LLNL clusters so far (3.9-3.12 appear available, and in case this difference is interesting: the 3.11 and 3.12 are anaconda installs, vs 3.9/3.10 being spack based. this has made a mess with things like mpi4py in the past, so could be some confounding factors there from anaconda)

[vsoch]

If you are testing this with the system install of flux python (the one that builds alongside flux, and not the external pip install bindings provided here) and the error occurs there, then it needs to be an issue opened on flux-core.

[grondo]

For some reason ~/.local/lib/python3.x/site-packages/_flux/_rlist.so is not available when I pip install flux-python. It is there in the RPM packaged versions, so I'm not sure what's going wrong in the flux-python build.

Also, when doing pip install flux-python is it supposed to install a version matching the installed flux? (I get 0.70.0 on corona, a system running 0.71.0)

[grondo]

Ah, well _rlist.so is specifically disabled:

flux-python/setup.py

Lines 72 to 77 in 6e1c1f3

	# Note that rlist is currently disabled, so this
	# set of metadata doesn't matter
	"rlist": {
	"header": "include/flux/rlist.h",
	"ignore_headers": ["czmq_containers"],
	},

Is this because flux-core doesn't install a librlist.so, and rlist.h headers, since that's internal only?

I'm afraid I don't know enough about how this all works to suggest a solution.

[vsoch]

Hmm I remember there was some issue about making the bindings for rlist - let's ask @trws.

[vsoch]

Also, when doing pip install flux-python is it supposed to install a version matching the installed flux? (I get 0.70.0 on corona, a system running 0.71.0)

No, there is no logic that determines that, you'd need to pip install the exact version. In this case, that is probably just the latest. I provide a script in the repository here that helps to match and then install a specific version, but it's just as easy to manually do it.

[grondo]

Ah, thanks @vsoch!

I wonder if flux-core needs to install a librlist in a non-default path for use in building bindings

[trws]

Ah, well _rlist.so is specifically disabled:

flux-python/setup.py

Lines 72 to 77 in 6e1c1f3

Note that rlist is currently disabled, so this

set of metadata doesn't matter

"rlist": {
"header": "include/flux/rlist.h",
"ignore_headers": ["czmq_containers"],
},
Is this because flux-core doesn't install a librlist.so, and rlist.h headers, since that's internal only?

I'm afraid I don't know enough about how this all works to suggest a solution.

Yeah, this is exactly why. If we want to support resource/rlist in the pip installed bindings that's exactly what we need.