B0FieldIdentifier: some characters should be replaced to set workflow name to avoid crashes in graph creation

[bpinsard]

FMRIPrep version 20.1.0
Not sure if that is in fMRIPrep or SDCFlows that the workflow name is set, but I get the following error if B0FieldIdentifier contains a - , and this will likely occur for other characters (I have no knowledge on dot files syntax though).

  File "/opt/conda/lib/python3.8/site-packages/fmriprep/cli/run.py", line 77, in main
    fmriprep_wf.write_graph(graph2use="colored", format="svg", simple_form=True)
  File "/opt/conda/lib/python3.8/site-packages/nipype/pipeline/engine/workflows.py", line 465, in write_graph
    outfname = format_dot(dotfilename, format=format)
  File "/opt/conda/lib/python3.8/site-packages/nipype/pipeline/engine/utils.py", line 1404, in format_dot
    formatted_dot, _ = _run_dot(dotfilename, format_ext=format)
  File "/opt/conda/lib/python3.8/site-packages/nipype/pipeline/engine/utils.py", line 1420, in _run_dot
    res = CommandLine(cmd, terminal_output="allatonce", resource_monitor=False).run()
  File "/opt/conda/lib/python3.8/site-packages/nipype/interfaces/base/core.py", line 428, in run
    runtime = self._run_interface(runtime)
  File "/opt/conda/lib/python3.8/site-packages/nipype/interfaces/base/core.py", line 822, in _run_interface
    self.raise_exception(runtime)
  File "/opt/conda/lib/python3.8/site-packages/nipype/interfaces/base/core.py", line 749, in raise_exception
    raise RuntimeError(
RuntimeError: Command:
dot -Tsvg -o"...../workdir/fmriprep_wf/graph.svg" ".../workdir/fmriprep_wf/graph.dot"
Standard output:

Standard error:
Error: ..../workdir/fmriprep_wf/graph.dot: syntax error in line 29 near '-'

dot file contains something like fmriprep_wf_single_subject_01_wf_fmap_preproc_wf_in_b0id-test on the offending line.

[bpinsard]

Replaced offending characters in my B0Field* tags and it works now, if that can help anyone encountering that issue.

[effigies]

Ah, thanks for that. I think we assumed it would be a camel case string.

[oesteban]

We use the B0FieldIdentifier as an entity at the output (estimated fieldmaps). But the B0FieldIdentifier can definitely have hyphens, so we probably want to revise the workflow names and the datasinks.