nwg-hello

nwg-hello

This program is a part of the nwg-shell project.

Nwg-hello is a GTK3-based greeter for the greetd daemon, written in python. It is meant to work under a Wayland compositor, like niri, sway or Hyprland (also see: Running on Debian and labwc). The greeter has been developed for the nwg-iso project, but it may be configured for standalone use.

The screen layout is heavily inspired by Sugar Candy SDDM theme by Marian Arlt.

Background

I was in need of a good login manager for the nwg-iso project. I first used SDDM with the Sugar Candy theme, and it worked pretty well. However, it brings QT dependencies, and my stuff is all GTK-based. Also, I know nothing about the QT framework, so couldn't adjust the greeter to my taste. The next choice was LightDM with my modification of the LightDM Elephant Greeter by Maximilian Moser. It looked well, but LightDM would happen to hang way too often. Then I gave a try to greetd, and that was it. I only needed a nice graphical greeter based on GTK3. Since there was no such thing, I had to develop one.

Features

• Multi-monitor support with gtk-layer-shell;
• multi-language support;
• background and style customization with CSS;
• automatic selection of the last used session and user;
• avatar (user picture) support;
• sound theme & login sound support (synchronized with nwg-look);
• support for setting environment variables.

Dependencies

• python >= 3.6;
• greetd;
• gtk3;
• gtk-layer-shell;
• some Wayland compositor (on my side tested on sway, Hyprland, Niri, and Mango;
• gnome-themes-extra.

Make dependencies

• python-build
• python-installer
• python-wheel
• python-setuptools

Optional dependencies

• mugshot: to set the user picture;
• gsound: for login sound playback support;
• sound-theme-freedesktop (or any GTK sound theme): system login sounds.

Installation


First, you need to install and start greetd.

The greeter can be installed as a package for your Linux distribution, or by cloning this repository and executing the install.sh script (make sure you installed dependencies first).

Then you need to edit the /etc/greetd/config.toml file (or greetd.conf - see the tip below).

[terminal]
# The VT to run the greeter on. Can be "next", "current" or a number
# designating the VT.
vt = 1

# The default session, also known as the greeter.
[default_session]

# `agreety` is the bundled agetty/login-lookalike. You can replace `/bin/sh`
# with whatever you want started, such as `sway`.
command = "agreety --cmd /bin/sh"

# The user to run the command as. The privileges this user must have depends
# on the greeter. A graphical greeter may for example require the user to be
# in the `video` group.
user = "greeter"

Replace the line:

command = "agreety --cmd /bin/sh"

with

command = "/usr/bin/start-hyprland -- -c /etc/nwg-hello/hyprland.conf"

if you want to use Hyprland, or this line if you prefer niri:

command = "niri -c /etc/nwg-hello/niri.kdl"

or this if you use mango:

command = "mango -c /etc/nwg-hello/mango.conf"

or this line if you prefer sway:

command = "sway -c /etc/nwg-hello/sway-config"

NOTE: you may need sway --unsupported-gpu for Nvidia. Also, if you'd like to make some additional configuration (e.g., monitor layout), edit /etc/nwg-hello/hyprland.conf, /etc/nwg-hello/niri.kdl, or /etc/nwg-hello/sway-config, or /etc/nwg-hello/mango.conf respectively.

Do not change the user = "greeter" line, or some file-related functions won't work.

Tip

During the greetd package upgrades, the config.toml file may be overwritten with the default one. E.g., on Arch Linux your modified file gets renamed to config.toml.pacsave. This will restore the agreety greeter on your system. To avoid such a situation, you may use the alternative greetd.conf file. This has not been mentioned in docs, but greetd looks for this file first. Just copy config.toml to greetd.conf and make changes to the copy.

Configuration

Copy /etc/nwg-hello/nwg-hello-default.json to /etc/nwg-hello/nwg-hello.json and make your changes there.

{
  "session_dirs": [
    "/usr/share/wayland-sessions",
    "/usr/share/xsessions"
  ],
  "custom_sessions": [
    {
      "name": "Shell",
      "exec": "/usr/bin/bash"
    }
  ],
  "monitor_nums": [],
  "form_on_monitors": [],
  "delay_secs": 1,
  "cmd-sleep": "systemctl suspend",
  "cmd-reboot": "systemctl reboot",
  "cmd-poweroff": "systemctl poweroff",
  "gtk-theme": "Adwaita",
  "gtk-icon-theme": "",
  "gtk-cursor-theme": "",
  "prefer-dark-theme": true,
  "template-name": "",
  "time-format": "%H:%M:%S",
  "date-format": "%A, %d. %B",
  "layer": "overlay",
  "keyboard-mode": "on_demand",
  "lang": "",
  "avatar-show": false,
  "avatar-size": 100,
  "avatar-border-width": 1,
  "avatar-border-color": "#eee",
  "avatar-corner-radius": 15,
  "avatar-circle": false,
  "play-login-sound-once": true,
  "login-sound-volume": "-10",
  "env-vars": []
}

• "session_dirs": comma-separated paths to session directories. Modify only if you know well what you're doing.
• "custom_sessions": greetd can run whatever starts from the command line. This way we can add bash, zsh or something else here. The "name" field is the display name. The "exec" field is a command.
• "monitor_nums": leave as is to see the greeter on all monitors. Set e.g. [0, 2] for it to appear on the 1st and 3rd one.
• "form_on_monitors": which of above monitors to display the login form on (just the wallpaper on the rest).
• "delay_secs": some monitors take longer to turn on. In the meantime the greeter may behave oddly on other monitors. If it happens to restart/blink, increase this value. If you only have one monitor and no discrete GPU, you may probably set 0 here.
• "cmd-sleep", "cmd-reboot", and "cmd-poweroff" are pre-defined for systemd-based systems. Use whatever works for you.
• "gtk-theme", "gtk-icon-theme" and "gtk-cursor-theme" are of little importance as long, as you use classes and IDs from the default css style sheet.
• "prefer-dark-theme" should remain true, unless you need to turn it off for use with your own background and/or styling.
• "template-name" allows use of own templates: find the built-in /usr/lib/python3.xx/site-packages/nwg_hello-x.y.z-py3.xx.egg/nwg_hello/template.glade file, copy to a folder somewhere in ~/, edit and place as /etc/nwg-hello/file-name.glade. Do not change widget IDs. Set your file-name.glade as the "template-name" value. Leave blank to use the built-in template.
• "time-format": string to format clock with the strftime() function (see: https://www.man7.org/linux/man-pages/man3/strftime.3.html).
• "date-format": string to format date with the strftime() function (see: https://www.man7.org/linux/man-pages/man3/strftime.3.html).
• "layer": allows choosing gtk-layer-shell layer: 'background', 'bottom', 'top', 'overlay'; 'overlay' will be used if no value given.
• "keyboard-mode": allows choosing gtk-layer-shell keyboard mode: 'none', 'exclusive', 'on_demand'; 'exclusive' will be used if no value given.
• "lang" allows you to force the use of a specific language, regardless of the $LANG system variable. Check if we have the translation in the langs directory.
• "avatar-show": determines whether to display the user's profile picture.
• "avatar-size": avatar image size in pixels.
• "avatar-border-width": avatar border width in pixels.
• "avatar-border-color": a hexadecimal value of avatar border color ("#rgb" or "#rrggbb").
• "avatar-corner-radius": corner radius for rectangular avatar image,
• "avatar-circle": draw avatar as a circle (corner radius ignored),
• "play-login-sound-once": set true to ensure the sound only plays once per boot session,
• "login-sound-volume": volume level in decibels (dB) as a string (e.g. "0" for standard volume, "-10" for lower volume (default)),
• "env-vars" allows to pass an array of environment variables. Use like this: ["MY_VAR=value", "OTHER_VAR=value1"].

Styling

Copy /etc/nwg-hello/nwg-hello-default.css to /etc/nwg-hello/nwg-hello.css and make your changes there.

Custom icons

If you'd like to use your own icons, do not replace /usr/share/nwg-hello/*-default.svg files. Place your poweroff.svg, reboot.svg, sleep.svg and avatar.svg files in the same directory. Attention: the avatar.svg file is not your profile picture, but a generic user image!

Own language files

You can't translate labels in the .glade file, as the program replaces the values with what's defined in language files. Since the 0.2.4 version, however, you can copy your lang file to /etc/nwg-hello/ and make desired changes there, see https://github.com/nwg-piotr/nwg-hello/issues/19. Be careful with syntax, the JSON format is unforgiving. Test your lang file by running nwg-hello -t -d from terminal.

User avatar

New in version 0.4.0. Disabled in default config. Set "avatar-show": true to enable.

The feature displays user's profile picture from /var/lib/AccountsService/icons/$USERNAME, stored by gnome-control-center or some other tool (Mugshot does the job perfectly well). See Configuration for related values.

Styling: no CSS is applicable here. You can set shape- and border-related values in config.

NOTE: if you use your customized /etc/nwg-hello/nwg-hello.json file, remember to copy all avatar-* key-value pairs from /etc/nwg-hello/nwg-hello-default.json.

Login sound

New in version 0.5.0. Requires nwg-look 1.2.1.

nwg-hello can play a startup sound based on your GTK sound theme preferences configured in nwg-look.

How it works:

1. When you click Apply in nwg-look, it exports your current sound theme name (gtk-sound-theme-name) and event sound toggle (gtk-enable-event-sounds) to /var/cache/nwg-hello/sound.json.
2. On startup, nwg-hello reads this file. If event sounds are enabled, it searches system-wide directories (/usr/share/sounds, /usr/local/share/sounds) for a desktop-login or service-login sound file (.oga, .ogg, .wav) matching the selected GTK theme (falling back to freedesktop).
3. If found, the sound is played once via GSound.

Note: Sound themes installed in user-local directories (such as ~/.local/share/sounds or ~/.sounds) will not work, as the greeter user runs in its own system context and has no access to individual user home directories. Only system-wide sound themes are supported.

Configuration in nwg-hello.json:

You can adjust the volume in /etc/nwg-hello/nwg-hello.json:

• "login-sound-volume": volume level in decibels (dB) as a string (e.g. "0" for standard volume, "-10" for lower volume (default)).
• "play-login-sound-once": true (default) to ensure the sound only plays once per boot session.

Note for packagers: /var/cache/nwg-hello/sound.json should be initialized via tmpfiles.d with 0666 permissions so nwg-look (running as a normal user) can write to it seamlessly.

Running on Debian and labwc

Submitted by @01micko.

configs

/etc/greetd/greetd.conf

[terminal]
# The VT to run the greeter on. Can be "next", "current" or a number
# designating the VT.
vt = 7

# The default session, also known as the greeter.
[default_session]

command = "labwc --config-dir /etc/nwg-hello/labwc-config"

# The user to run the command as. The privileges this user must have depends
# on the greeter. A graphical greeter may for example require the user to be
# in the `video` group.
user = "_greetd"

NOTE: The user _greetd is a debian thing, even though it isn't set up correctly. You have to manually add to 'video' group and chown all the files in /etc/greetd.

/etc/nwg-hello/labwc-config/autostart

# start nwg-hello - full paths aren't required, but saves lookup time
exec /usr/bin/nwg-hello; /usr/bin/labwc --exit

/etc/nwg-hello/labwc-config/rc.xml (optional)

• only if you want a screenshot (using PrtScr key) of nwg-hello saved to /etc/greetd/

 <?xml version="1.0" ?>
<labwc_config>

  <keyboard>
    <default />
    <keybind key="Print"><action name="Execute" command="grim" /></keybind>
  </keyboard>

</labwc_config>

Session files on NixOS

On NixOS it may be necessary to add "/share/wayland-sessions" and/or "/share/xsessions" to environment.pathsToLink to ensure that the session files are available in the correct location.

Acknowledgments

• @milisarge for the snippet that let me know how things work;
• Marian Arlt for inspiring look of the Sugar Candy SDDM theme.