[Feature Request]

[jgbos]

🚀 Feature Request

Allow configurable plugins without use of hydra_plugin package. This is especially useful for hydra-zen users.

Motivation

I do not want to create launchers that must be installed as a package, I just want to configure my own function in my repo.

Pitch

Remove the hard runtime error here https://github.com/facebookresearch/hydra/blob/main/hydra/core/plugins.py#L102.

Suggested fix:

if not self.is_in_toplevel_plugins_module(classname):
    # All plugins must be defined inside the approved top level modules.
    # For plugins outside of hydra-core, the approved module is hydra_plugins.
    raise RuntimeError(f"Invalid plugin '{classname}': not the hydra_plugins package")

if classname not in self.class_name_to_class.keys():
    raise RuntimeError(f"Unknown plugin class : '{classname}'")
clazz = self.class_name_to_class[classname]
plugin = instantiate(config=config, _target_=clazz)

to

if self.is_in_toplevel_plugins_module(classname):
      if classname not in self.class_name_to_class.keys():
          raise RuntimeError(f"Unknown plugin class : '{classname}'")
      clazz = self.class_name_to_class[classname]
      plugin = instantiate(config=config, _target_=clazz)
else:
      plugin = instantiate(config=config)