Shell

class shell_logger.shell.Shell(pwd=None, *, login_shell=False)

Bases: object

Manage interactions with the underlying shell.

Spawns a shell subprocess that inherits five unnamed pipes (stdout, stderr, stdin, aux_stdout, aux_stderr).

login_shell

Whether or not the spawned shell should be a login shell.

Type:

bool

aux_stdin_rfd

The read file descriptor for stdin.

Type:

int

aux_stdin_wfd

The write file descriptor for stdin.

Type:

int

aux_stdout_rfd

The read file descriptor for stdout.

Type:

int

aux_stdout_wfd

The write file descriptor for stdout.

Type:

int

aux_stderr_rfd

The read file descriptor for stderr.

Type:

int

aux_stderr_wfd

The write file descriptor for stderr.

Type:

int

shell_subprocess

The subprocess for interacting with the shell.

Type:

Popen[str]

Initialize a Shell object.

Parameters:

• pwd (Optional[Path]) – The directory to change to when starting the Shell.

• login_shell (bool) – Whether or not the spawned shell should be a login shell.

auxiliary_command(**kwargs)

Run auxiliary commands like umask, pwd, env, etc.

Parameters:

**kwargs – Additional arguments.

Note: This is effectively the same as run(), but:

1. The stdout and stderr get redirected to the auxiliary file descriptors.

2. You don’t tee the stdout or stderr.

Todo

• Maybe combine this with run() with extra flags.

• Replace **kwargs with function arguments.

Return type:

Tuple[Optional[str], Optional[str]]

Returns:

The stdout and stderr of the command run.

cd(path)

Change to the given directory.

Parameters:

path (Path) – The directory to change to.

Return type:

None

pwd()

Get the current working directory.

Return type:

str

Returns:

The current working directory.

run(command, **kwargs)

Run a command in the underlying shell.

Write a command to the Shell class’ shell subprocess’ stdin, and pull the stdout and stderr.

Parameters:

• command (str) – The command to run in the shell subprocess.

• **kwargs – Any additional arguments to pass to tee().

Return type:

SimpleNamespace

Returns:

The command run, along with its return code, stdout, stderr, start/stop time, and duration.

static tee(stdout, stderr, **kwargs)

Write output/error streams to multiple files.

Split stdout and stderr file objects to write to multiple files.

Parameters:

• stdout (Optional[IO[bytes]]) – The stdout file object to be split.

• stderr (Optional[IO[bytes]]) – The stderr file object to be split.

• **kwargs – Additional arguments.

Return type:

SimpleNamespace

Returns:

The stdout and stderr as strings.

Todo

• Replace **kwargs with function arguments.