"Local" plugins

I would like to be able to “locally” register a plugin, within a bounded context. An example would be a library where I know, locally that I would be dealing with “.dat” / “.raw” files which actually have a certain binary format, so I want to register a plugin for these, but I don’t want this plugin to affect the entire Python process (because “.dat”/“.raw” could be anything, and I don’t want to make promises for other modules in the same process that could also be using imageio). IOW, I’d like something like (API names up to bikeshedding)

def my_libs_public_api(path: Path, ...):
    # path can be a .dat/.raw, or perhaps any other format supported by imageio
    imopen_with_extra_plugins = imopen.with_plugins(extra_plugins)  # perhaps instantiated at module level
    with imopen_with_extra_plugins(path, "r") as file: return file.read()

I think this is “mostly” just a matter of having an extra class attribute _instance_plugins, which is checked before _known_plugins, have with_plugins return a new imopen instance with extra entries in _instance_plugins, and check _instance_plugins before _known_plugins in imopen.__call__.

Thoughts?

[FirefoxMetzger]

Awesome.

@almarklein Any objections to extending support of plugin in imopen(..., plugin=...) to allow plugin classes as input?

@anntzer Would you be interested in contributing this feature?

[anntzer]

Not now, but I’ll keep this somewhere in the back of my mind.