utils/gatelock
Krzysztof Rudnicki 28ced1d39a Cover the last branches of the viewport, the density scale and the keys
gatelock has never met its own 100% bar; _scrollable.py in particular shipped
with no tests at all, which is how a viewport that scrolled itself passed
every check for a week. The remaining gaps were the ones a reader would most
want proven:

* finalize() is documented idempotent -- a repaint calls it again, and an
  earlier version stacked a <FocusIn> handler per call.
* scroll_into_view holds still for a widget already fully on screen. Its
  margin logic has three outcomes and "hold" is the one a jittering viewport
  gets wrong.
* the type scale reads an existing Tk root rather than opening a second one
  next to a live lock window.
* bind_cancel rejects a non-callable at bind time, not on the keypress that
  finally needed Escape to work.

328 tests, coverage 99.44% -> 100.00%.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BsXnTHyuuCUZsqetTaajcF
2026-08-03 16:20:11 +02:00
..
gatelock Cover the last branches of the viewport, the density scale and the keys 2026-08-03 16:20:11 +02:00
.pre-commit-config.yaml Stop the recovery tick stealing our own grab, and fix pre-commit for the monorepo 2026-07-26 15:08:41 +02:00
LICENSE Initial gatelock: shared lock-window + HMAC log-integrity backend 2026-06-19 17:39:44 +02:00
pyproject.toml gatelock 0.4.0: the viewport moves for the user and nobody else 2026-08-03 15:50:51 +02:00
README.md gatelock: warm-tint the unified-design-system palette, add on-fill token 2026-07-21 21:11:07 +02:00
requirements.txt Initial gatelock: shared lock-window + HMAC log-integrity backend 2026-06-19 17:39:44 +02:00

gatelock

Shared fullscreen lock-window + HMAC log-integrity backend, extracted from three personal automation tools that each independently implemented "lock the screen with a blocking overlay until a condition is met": diet_guard, wake_alarm, and screen-locker.

Why

All three reimplemented the same tkinter fullscreen mechanics (overrideredirect, input grab, VT-switch disable) at different levels of maturity, and the HMAC-signed-state module had already been hand-copied between two of them because they live in separate repos. gatelock is the one place that logic now lives.

Install

pip install "gatelock @ git+https://github.com/kuhyx/utils@gatelock-v0.1.1#subdirectory=gatelock"

Usage

import tkinter as tk
from gatelock import GateRoot, LockConfig, LockWindow

class MyGate:
    def __init__(self, *, demo_mode: bool) -> None:
        self.root = GateRoot()
        self.root.on_callback_error = self._handle_callback_error
        config = LockConfig(mode="soft" if demo_mode else "hard")
        self._lock = LockWindow(self.root, config, hooks=self)
        self._lock.setup()
        # ... build your widgets ...
        self._lock.grab_input()

    def on_focus_ready(self) -> None:
        self.my_entry.focus_force()

    def on_callback_error(self) -> None:
        self.close()

    def on_close(self) -> None:
        ...  # release any hardware/state held while locked

    def close(self) -> None:
        self._lock.close()

    def run(self) -> None:
        self._lock.run()

LockConfig's mode preset bundles the common combination ("soft" = topmost only, typeable, WM-escapable; "hard" = overrideredirect + global grab + VT-disable). Each axis (overrideredirect, grab, disable_vt, grab_retry_ms) can be set explicitly to reproduce a consumer's exact prior behavior where it diverges from the preset.

gatelock.log_integrity ports the HMAC-signed state module used by all three projects; DEFAULT_HMAC_KEY_FILE (/etc/workout-locker/hmac.key) is unchanged so existing signed history keeps verifying.

Development

python -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
pytest
pre-commit install && pre-commit install --hook-type pre-push