Hey Hsin-Fang Chiang —

I understood from the discussion above that it was necessary that all the dependencies of ci_hsc be converted to use pex_logging before it was possible to convert ci_hsc itself. However, I just tried running the tickets/DM-8356 branch of ci_hsc with the latest weekly (w51) of meas_modelfit which pre-dates the logging conversion, and it worked fine!

Can you explain a bit what's going on here? Do dependencies need to be converted or not? How do the logging systems interact?

Thanks!

I said it's possible (not necessary!) that dependent packages need to remove pex_logging first. From my experience, the dependency blocking sometimes happened in c++ codes; mostly it was afw and somehow I couldn't remove downstream pex_logging dependency in c++ while afw still used pex_logging. I suspected it was some SWIG thing but didn't follow through to know exactly why. If you are really curious I may go back to find an example.

On second thought, it's indeed puzzling how meas_modelfit could block ci_hsc. There seems no log passing, and after all, ci_hsc is pure python, right? I didn't try anything practical here. Maybe Perry Gee can say more what he saw?

No, it's not pure python. It runs the pipeline, which calls C++ for most of its measurement algorithms. The problem was occurring in swig I believe, though it has been weeks, and I don't really recall. I never tracked down the smoking gun, nor did I feel motivated to do so when the problem when away. But I will try to reproduce it when I have the time. I may not have been in the build and setup state I thought I was.

Change looks basically fine. Trivial comment on the PR.

As a reminder, our procedure is that the author of the code makes the PR before they submit it for review. See e.g. here.