interactive

Interactive module.

exception wmflib.interactive.InputError

Bases: wmflib.exceptions.WmflibError

Custom exception class raised on invalid input from the user in interactive mode.

exception wmflib.interactive.AbortError

Bases: wmflib.exceptions.WmflibError

Custom exception class raised when an action is manually aborted.

wmflib.interactive.ask_input(message: str, choices: Sequence[str]) → str

Ask the user for input in interactive mode.

Examples

>>> choices = ['A', 'B']
>>> response = ask_input(f'Choose a door between {choices}', choices)
==> Choose a door between ['A', 'B']
> a
==> Invalid response, please type one of: A,B. After 3 wrong answers the task will be aborted.
> A
>>> response
'A'

Parameters

• message (str) – the message to be printed before asking for confirmation.

• choices (sequence) – the available choices of possible answers that the user can give. Values must be strings.

Returns

the selected choice.

Return type

str

Raises

wmflib.interactive.InputError – if not in a TTY or on too many invalid answers.

wmflib.interactive.ask_confirmation(message: str) → None

Ask the use for confirmation in interactive mode.

Examples

>>> ask_confirmation('Ready to continue?')
==> Ready to continue?
Type "go" to proceed or "abort" to interrupt the execution
> go
>>> ask_confirmation('Ready to continue?')
==> Ready to continue?
Type "go" to proceed or "abort" to interrupt the execution
> abort
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/wmflib/interactive.py", line 69, in ask_confirmation
    raise AbortError('Confirmation manually aborted')
wmflib.interactive.AbortError: Confirmation manually aborted

Parameters

message (str) – the message to be printed before asking for confirmation.

Raises

• wmflib.interactive.InputError – if not in a TTY or on too many invalid answers.

• wmflib.interactive.AbortError – if manually aborted.

wmflib.interactive.confirm_on_failure(func: Callable, *args: Any, **kwargs: Any) → Any

Execute a function asking for confirmation to retry, abort or skip.

Examples

>>> def test(fail=False):
...     if fail:
...         raise RuntimeError('Failed')
...
>>> confirm_on_failure(test)
>>> confirm_on_failure(test, fail=True)
Failed to run __main__.test: Failed
==> What do you want to do? "retry" the last command, manually fix the issue and "skip" the last command to
    continue the execution or completely "abort" the execution.
> retry
Failed to run __main__.test: Failed
==> What do you want to do? "retry" the last command, manually fix the issue and "skip" the last command to
    continue the execution or completely "abort" the execution.
> skip
>>>

Parameters

• func (callable) – the function/method to execute.

• *args (mixed) – all the positional arguments to pass to the function/method.

• *kwargs (mixed) – all the keyword arguments to pass to the function/method.

Returns

what the called function returns, or None if the execution should continue skipping this step because has been manually fixed.

Return type

mixed

Raises

wmflib.interactive.AbortError – on manually aborted tasks.

wmflib.interactive.get_username() → str

Detect and return the name of the effective running user even if run as root.

Examples

>>> get_username()
'user'

Returns

the name of the effective running user or - if unable to detect it.

Return type

str

wmflib.interactive.ensure_shell_is_durable() → None

Ensure it is running either in non-interactive mode or in a screen/tmux session, raise otherwise.

Examples

>>> ensure_shell_is_durable()  # Will raise if not in a tmux/screen session
>>>

Raises

wmflib.exceptions.WmflibError – if in a non-durable shell session.

wmflib.interactive.get_secret(title: str, *, confirm: bool = False) → str

Ask the user for a secret e.g. password.

Examples

>>> secret = get_secret('Secret key')
Secret key:
Secret must be at least 6 characters. try again:
>>> secret = get_secret('Secret key', confirm=True)  # Will raise if the confirmation doesn't match
Secret key:
Again, just to be sure:
>>>

Parameters

• title (str) – The message to show the user.

• confirm (bool, optional) – If True ask the user to confirm the password.

Returns

the secret.

Return type

str

Raises

wmflib.exceptions.WmflibError – if the password confirmation does not match and confirm is True.