No user feedback when pantsd fails to start

[asherf]

Where there is an issue w/ pantd config, it is only visible if you look at the log file.
Running pants just says that pantsd didn't start:

The error should be sent back to the client and show to the user.

from pantsd log:

00:21:03:034 [INFO] terminating pantsd
00:21:03:036 [WARN] /data/home/asher/.cache/pants/setup/bootstrap-Linux-x86_64/1.29.0.dev1_py38/lib/python3.8/site-packages/pants/base/exception_sink.py:359: DeprecationWarning: PY_SSIZE_T_CLEAN will be required for '#' formats
  process_title=setproctitle.getproctitle(),

00:21:03:036 [ERROR] service failure for <pants.pantsd.service.scheduler_service.SchedulerService object at 0x7ffb836a2940>, shutting down!
NoneType: None
15:08:23:519 [INFO] setting up service <pants.pantsd.service.scheduler_service.SchedulerService object at 0x7ffac4bf2f40>
15:08:23:525 [WARN] /data/home/asher/.cache/pants/setup/bootstrap-Linux-x86_64/1.29.0rc1_py38/lib/python3.8/site-packages/pants/base/exception_sink.py:359: DeprecationWarning: PY_SSIZE_T_CLEAN will be required for '#' formats
  process_title=setproctitle.getproctitle(),

15:08:23:526 [ERROR] 1 Exception encountered:

  Exception: Failed to parse PathGlobs: Failed to parse PathGlobs for globs(["!*.pyc", "!/src/python/curator/", REDACTED])
NoneType: None
15:09:16:908 [INFO] setting up service <pants.pantsd.service.scheduler_service.SchedulerService object at 0x7fc2df2a4cd0>
15:09:16:911 [WARN] /data/home/asher/.cache/pants/setup/bootstrap-Linux-x86_64/1.29.0rc1_py38/lib/python3.8/site-packages/pants/base/exception_sink.py:359: DeprecationWarning: PY_SSIZE_T_CLEAN will be required for '#' formats
  process_title=setproctitle.getproctitle(),

15:09:16:912 [ERROR] 1 Exception encountered:

  Exception: Failed to parse PathGlobs: Failed to parse PathGlobs for globs(["!*.pyc", "!/src/python/curator/", REDACTED])
NoneType: None

@stuhood

[stuhood]

Thanks for the report. This is somewhat specific to that particular option (which is consumed by the daemon itself). This will be addressed in the same cluster of issues as #8200 and #7654.

[asherf]

at the very least, if the pants client fails to talk to pantsd, before exiting it should either point the user to look for errors in the pantsd log file or just read the error from there and show it to the user.

[stuhood]

Mm, yep. Good idea.

[stuhood]

#10035 should fix this issue for 95% of cases, because the client will render Scheduler/service creation errors in the foreground.

I'm going to leave it open to track the last 5%, which should be addressed during #9402.

[stuhood]

Based on messing around with some very broken plugin code, I think that we can call this solved by #10035... it's pretty hard to repro an issue anymore. Huzzah!