Using Hydra Configuration inside Classes

Question

I am trying to use the hydra tool in my project and would like to use the decorator for class functions

import hydra
from hydra.core.config_store import ConfigStore

from src.config import RecordingConfig

cs = ConfigStore.instance()
cs.store(name="recording_config", node=RecordingConfig)

class HydraClassTest:
    @hydra.main(config_path="../src/conf/", config_name="conf")
    def __init__(self, conf: RecordingConfig):
        print(conf)

def main():
    HydraClassTest()

if __name__ == "__main__":
    main()

But I get the error

TypeError: __init__() missing 1 required positional argument: 'conf'

Is this intended and should I pass the configuration from the outside to the class? (For example by using the decorator on the main function and passing the configuration as a parameter to the initializer, this works)
Or am using the decorator in a wrong way? If it is intended, is there some design reason why one would not want to do it that way?

I have checked whether I used the decorator correctly by passing the configuration through the main function, that worked.

import hydra
from hydra.core.config_store import ConfigStore

from src.config import RecordingConfig

cs = ConfigStore.instance()
cs.store(name="recording_config", node=RecordingConfig)

class HydraClassTest:
    def __init__(self, conf: RecordingConfig):
        print(conf)

@hydra.main(config_path="../src/conf/", config_name="conf")
def main(conf: RecordingConfig):
    HydraClassTest(conf)

if __name__ == "__main__":
    main()

This gives me the expected result.

Answer 1

@hydra.main() is not appropriate for this use case. It's designed to be used once in an application and it has many side effects (changing working directory, configuring logging etc).

Use the Compose API instead.