Environment variables

Save constants and secrets to an .env file to make them available to UDFs as environment variables.

First, run a File UDF that sets variables in an .env file in the /mnt/cache/ directory.

@fused.udf
def udf():
    env_vars = """
    MY_ENV_VAR=123
    DB_USER=username
    DB_PASS=******
    """

    # Path to .env file in disk file system
    env_file_path = '/mnt/cache/.env'

    # Write the environment variables to the .env file
    with open(env_file_path, 'w') as file:
        file.write(env_vars)

Now, any UDF can load the values from .env as environment variables with the load_dotenv and access them with os.getenv.

@fused.udf
def udf():
    from dotenv import load_dotenv

    # Load environment variable
    env_file_path = '/mnt/cache/.env'
    load_dotenv(env_file_path, override=True)

    # Access environment variable
    print(f"Updated MY_ENV_VAR: {os.getenv('MY_ENV_VAR')}")