import logging
import signal
import sys
-from typing import List
+from typing import List, Optional
import readchar # type: ignore
def single_keystroke_response(
- valid_responses: List[str],
+ valid_responses: Optional[List[str]], # None = accept anything
*,
prompt: str = None,
default_response: str = None,
timeout_seconds: int = None,
-) -> str:
+) -> Optional[str]: # None if timeout w/o keystroke
"""Get a single keystroke response to a prompt."""
def _handle_timeout(signum, frame) -> None:
raise exceptions.TimeoutError()
def _single_keystroke_response_internal(
- valid_responses: List[str], timeout_seconds=None
+ valid_responses: Optional[List[str]], timeout_seconds: int = None
) -> str:
os_special_keystrokes = [3, 26] # ^C, ^Z
if timeout_seconds is not None:
while True:
response = readchar.readchar()
logger.debug('Keystroke: 0x%x', ord(response))
- if response in valid_responses:
+ if not valid_responses or response in valid_responses:
break
if ord(response) in os_special_keystrokes:
break
if timeout_seconds is not None:
signal.alarm(0)
+ response = None
if prompt is not None:
print(prompt, end="")
sys.stdout.flush()
except exceptions.TimeoutError:
if default_response is not None:
response = default_response
- if prompt is not None:
+ if prompt and response:
print(response)
return response
-def yn_response(prompt: str = None, *, timeout_seconds=None) -> str:
+def yn_response(prompt: str = None, *, timeout_seconds=None) -> Optional[str]:
"""Get a Y/N response to a prompt."""
- return single_keystroke_response(
+ yn = single_keystroke_response(
["y", "n", "Y", "N"], prompt=prompt, timeout_seconds=timeout_seconds
- ).lower()
+ )
+ if yn:
+ yn = yn.lower()
+ return yn
+
+
+def press_any_key(
+ prompt: str = "Press any key to continue...", *, timeout_seconds=None
+) -> Optional[str]:
+ """Press any key to continue..."""
+
+ return single_keystroke_response(None, prompt=prompt, timeout_seconds=timeout_seconds)
def keystroke_helper() -> None: