Version: 1.0

Output/Working directory

Example

Hydra solves the problem of your needing to specify a new output directory for each run, by creating a directory for each run and executing your code within that working directory.

The working directory is used to:

  • Store the output for the application (For example, a database dump file)
  • Store the Hydra output for the run (Configuration, Logs etc)

Every time you run the app, a new working directory is created:

Python file: my_app.py

import os
from omegaconf import DictConfig
@hydra.main()
def my_app(cfg: DictConfig) -> None:
print("Working directory : {}".format(os.getcwd()))
$ python my_app.py
Working directory : /home/omry/dev/hydra/outputs/2019-09-25/15-16-17
$ python my_app.py
Working directory : /home/omry/dev/hydra/outputs/2019-09-25/15-16-19

Let's take a look at one of the working directories:

$ tree outputs/2019-09-25/15-16-17
outputs/2019-09-25/15-16-17
โ”œโ”€โ”€ .hydra
โ”‚ โ”œโ”€โ”€ config.yaml
โ”‚ โ”œโ”€โ”€ hydra.yaml
โ”‚ โ””โ”€โ”€ overrides.yaml
โ””โ”€โ”€ my_app.log

We have the Hydra output directory (.hydra by default) and the application log file. Inside the configuration output directory we have:

  • config.yaml: A dump of the user specified configuration
  • hydra.yaml: A dump of the Hydra configuration
  • overrides.yaml: The command line overrides used

And in the main output directory:

  • my_app.log: A log file created for this run

Disabling output subdir

You can change the .hydra subdirectory name by overriding hydra.output_subdir. You can disable its creation by overriding hydra.output_subdir to null.

Original working directory

You can still access the original working directory if you need to:

import os
from omegaconf import DictConfig
import hydra
@hydra.main()
def my_app(_cfg: DictConfig) -> None:
print(f"Current working directory : {os.getcwd()}")
print(f"Orig working directory : {hydra.utils.get_original_cwd()}")
print(f"to_absolute_path('foo') : {hydra.utils.to_absolute_path('foo')}")
print(f"to_absolute_path('/foo') : {hydra.utils.to_absolute_path('/foo')}")
if __name__ == "__main__":
my_app()
$ python examples/tutorial/8_working_directory/original_cwd.py
Current working directory : /Users/omry/dev/hydra/outputs/2019-10-23/10-53-03
Original working directory : /Users/omry/dev/hydra
to_absolute_path('foo') : /Users/omry/dev/hydra/foo
to_absolute_path('/foo') : /foo

Working directory can be customized.

Last updated on by Omry Yadan