nightlight

A CLI for configuring "Night Shift" on macOS 🌕🌖🌗🌘🌑

This crate also doubles as a Rust library. 🦀

Why?

The "Night Shift" feature on macOS is a convenient, built-in feature that can theoretically accomplish most of what third-party alternatives (like f.lux®) are capable of. However, as of now, there is no way to programmatically configure Night Shift (without entering the system preferences GUI), making its current usage more limited.

This nightlight CLI aims to enable such access via a few simple commands. (Or, alternatively, via library access for other Rust tools.)

Installing

via Homebrew

brew tap smudge/smudge
brew install nightlight

via Cargo

Set up Rust/Cargo and install from crates.io by running:

cargo install nightlight

Usage

First, make sure you are running macOS Sierra or newer.

Command-Line Interface

Manual On/Off:

Turn Night Shift on (until tomorrow/sunrise):

nightlight on

Turn Night Shift off:

nightlight off

View current on/off status:

nightlight status

Controlling the Temperature:

View current temperature setting:

nightlight temp

Set color temperature (a number from 0 to 100):

nightlight temp 70

Scheduling:

View the current schedule:

nightlight schedule

Start schedule from sunset to sunrise:

nightlight schedule start

Start a custom schedule (in 12 or 24-hour time format):

nightlight schedule 19:45 6:00
nightlight schedule 7:45pm 6am

Stop the current schedule:

nightlight schedule off

Rust API

In addition to a CLI, nightlight can be pulled-in as a dependency for other Rust crates:

nightlight = "0.2.0"

Here's an example fn that toggles Night Shift off, changes the schedule and color temperature preference, and then toggles the feature back on:

extern crate nightlight;

use nightlight::{NightLight, Schedule};

fn main() {
    let night_light = NightLight::new();

    if night_light.status().is_on() {
        night_light.off().unwrap(),
    }

    println!("Setting schedule and temperature...");
    night_light.set_schedule(Schedule::SunsetToSunrise).unwrap();
    night_light.set_temp(70).unwrap();

    println!("Turning Night Shift on...");
    night_light.on().unwrap();
}

Todo:

• Ability to see current status of Night Shift
• Ability to enable/disable sunrise/sundown schedule
• Ability to enable/disable custom schedules
• Ensure that changing schedule doesn't affect on/off state.
• Make time display as properly-formatted 12-hour time
• Use system config for time parse/format (12 vs 24).
• API improvements
• Consider command outputs: concise, human-readable, machine-parsable.
• Full lib documentation
• Test coverage of schedule/time parsing.
• Tests that use fake/stub ObjC library.
• Support for "Automatically adjust brightness" feature.
• Other release mechanisms (like brew)
• Cross-platform support (e.g. Windows' "Night Light")

Contributing

• Check the issue tracker and consider creating a new issue.
• Fork the project and create a new branch for your contribution.
• Write, commit, and push your contribution to your branch.
• Make sure the project builds (cargo build) and functionality still works as expected.
• Submit a pull request.

Thanks To:

• The team at Apple for introducing this feature in macOS Sierra
• GitHub user jenghis for the (now archived) nshift repo/CLI
• The maintainers of the Rust objc crate
• Carol Nichols and Steve Klabnik for the official book on Rust
• ABH, AF, CB, JP, and MK for brainstorming crate names with me

License

nightlight is released under the MIT License.