Files
Jackify/jackify/frontends/cli/ui/indeterminate_status.py
2026-03-13 14:43:25 +00:00

71 lines
2.2 KiB
Python

"""Single-line CLI pulser for indeterminate background stages."""
from __future__ import annotations
import itertools
import sys
import threading
import time
from typing import Optional
class CliIndeterminateStatus:
"""Render one in-place pulsing status line for long-running CLI steps."""
def __init__(self, output=None, interval: float = 0.12):
self._output = output or sys.stdout
self._interval = interval
self._interactive = bool(getattr(self._output, "isatty", lambda: False)())
self._message: Optional[str] = None
self._printed_message: Optional[str] = None
self._stop_event = threading.Event()
self._lock = threading.Lock()
self._thread: Optional[threading.Thread] = None
def set(self, message: str) -> None:
"""Start or update the active pulsing message."""
cleaned = (message or "").strip()
if not cleaned:
self.stop()
return
if not self._interactive:
if cleaned != self._printed_message:
print(cleaned, file=self._output, flush=True)
self._printed_message = cleaned
return
with self._lock:
self._message = cleaned
if self._thread and self._thread.is_alive():
return
self._stop_event.clear()
self._thread = threading.Thread(target=self._run, daemon=True)
self._thread.start()
def stop(self) -> None:
"""Stop the pulser and clear its terminal line."""
if not self._interactive:
return
self._stop_event.set()
if self._thread and self._thread.is_alive():
self._thread.join(timeout=0.5)
self._thread = None
with self._lock:
self._message = None
self._output.write("\r\033[2K")
self._output.flush()
def close(self) -> None:
self.stop()
def _run(self) -> None:
for frame in itertools.cycle("|/-\\"):
if self._stop_event.wait(self._interval):
return
with self._lock:
message = self._message
if not message:
continue
self._output.write(f"\r\033[2K{message} {frame}")
self._output.flush()