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Version: 1.2

A simple command-line application

Β Example (Click Here)

This is a simple Hydra application that prints your configuration. The my_app function is a place holder for your code. We will slowly evolve this example to showcase more Hydra features.

The examples in this tutorial are available here.

my_app.py
from omegaconf import DictConfig, OmegaConf
import hydra

@hydra.main(version_base=None)
def my_app(cfg: DictConfig) -> None:
print(OmegaConf.to_yaml(cfg))

if __name__ == "__main__":
my_app()

In this example, Hydra creates an empty cfg object and pass it to the function annotated with @hydra.main.

You can add config values via the command line. The + indicates that the field is new.

$ python my_app.py +db.driver=mysql +db.user=omry +db.password=secret
db:
driver: mysql
user: omry
password: secret
info

See the version_base page for details on the version_base parameter.

See Hydra's command line flags and Basic Override Syntax for more information about the command line.