WSL Windows Toolbar Launcher

This script will create a Windows toolbar launcher for an underlying WSL install which can be used to fire up linux native applications directly from Windows via the standard Windows toolbar, like this:

It's particularly cool because WSL 2 is coming which is unlocking unprecedented performance and compatibility improvements, so this will literally bring the full suite of Linux GUI applications directly to Windows UI.

Prerequisites

The script expects to be run within the WSL execution environment with:

A complete WSL install ready with bash and python3 installed.
An X11 Server running on your windows host (e.g. X410, Xming etc). This server must be reachable from your WSL env (test with something like wsl.exe -- source ~/.bashrc ; xterm"). If this fails, check your DISPLAY variable (more details in troubleshooting).
A desktop environment which has a freedesktop menu installed (e.g. gnome / xfce).

And optionally (but recommended):

An installation of cairosvg if works on your distro (pip install cairosvg)
Imagemagick installed (sudo apt install imagemagick / dnf install imagemagick etc)

Installing and Running

To install:

pip install wsl-windows-toolbar

To run:

wsl-windows-toolbar

After installation, right click on your toolbar, go to Toolbars -> New toolbar... and select %USERPROFILE%\.config\wsl-windows-toolbar-launcher\menus\WSL as the target folder (unless you selected an alternative directory).

Note there are many options available with --help if you'd prefer to use alternative locations.

Updating

If new software has been installed in the WSL environment, simply run the script again from the WSL environment to pick the new GUIs up.

Notable changes:

Change in 0.3: Command is now wsl-windows-toolbar without the trailing .py.

Advanced Usage / Options

$ python wsl-windows-toolbar.py  --help
Usage: wsl_windows_toolbar.py [OPTIONS]

Options:
  -i, --install-directory PATH    Install the launchers here [default:
                                  /c/Users/$USER/.config/wsl-windows-toolbar-
                                  launcher/metadata]
  -m, --metadata-directory PATH   Install any metadata here [default:
                                  /c/Users/$USER/.config/wsl-windows-toolbar-
                                  launcher/metadata]
  -d, --distribution TEXT         WSL Distro to generate shortcuts for
                                  [default: $WSL_DISTRO_NAME]
  -u, --user TEXT                 WSL Distro's user to launch programs as
                                  [default: $USER]
  -y, --confirm-yes               Assume the answer to all confirmation
                                  prompts is 'yes'  [default: False]
  -f, --menu-file FILENAME        The *.menu menu file to parse  [default:
                                  /etc/xdg/menus/gnome-applications.menu]
  -w, --wsl-executable TEXT       Path to the WSL executable relative to the
                                  windows installation  [default:
                                  C:\Windows\System32\wsl.exe]
  -n, --target-name TEXT          Name to give to the created installation
                                  (will be displayed in toolbar menu)
                                  [default: WSL]
  -t, --preferred-theme TEXT      Preferred menu theme to use  [default:
                                  Adwaita]
  -T, --alternative-theme TEXT    Alternative menu themes to consider (pass
                                  multiple times)  [default: Papirus,
                                  Humanity, elementary-xfce]
  -j, --jinja-template-batch FILENAME
                                  Optional Jinja template to use instead of
                                  the inbuilt default (advanced users only)
  -J, --jinja-template-shell FILENAME
                                  Optional Jinja template to use instead of
                                  the inbuilt default (advanced users only)
  -r, --rc-file FILENAME          Optional rc file to source prior to
                                  launching the command instead of ~/.bashrc
  -D, --launch-directory DIRECTORY
                                  Optional default linux path to open
                                  applications relative to (defaults to ~)
  --help                          Show this message and exit.

Advanced Launcher Behaviour

The launcher process is fairly broken down to separate responsibilities and allow customizations at several layers. It looks like this:

lnk -> vbscript (sometimes) -> bat -> wsl bash -> app

The .lnk is the shortcut with the icon etc. The vbscript exists only to launch the batch file without a terminal window appearing. The batch file bootstraps the wsl bash script using wsl.exe which in turn (finally) launches the app. It may seem convoluted but I have found this is the easiest way to break it down to allow flexibility and ease of maintenance at each layer.

Note the vbscript is only called if run_in_terminal is set to false (as it tends to be for most applications). The templates which define the batch and bash files are used may be overridden by -j and -J respectively, though you shouldn't usually need to override this behaviour.

The default templates used are wsl-windows-toolbar-template.bat.j2 and wsl-windows-toolbar-template.sh.j2. The following possible variables passed through from the script:

distribution: The distribution selected in the script
user: The user selected in the script
command: The individual command for each launcher entry in WSL environment (e.g. xterm)
wsl: The wsl executable discovered
rcfile: The rc file (e.g. .bashrc) to source prior to launch selected in the script
launch_script: The path of the linux launcher script
exec_dir: The directory in which this command will be run (linux path)
run_in_terminal: Boolean specifying whether or not this app expects to run in a terminal

Troubleshooting

No applications launching

If no applications are launching at all, it's most likely an issue with either:

DISPLAY not being set correctly
DISPLAY being set fine, but its destination is not accessible from the WSL environment
The X11 server isn't set up to allow access from external hosts (how to configure this will depend on your X11 server so please refer to their documentation)

Note that for this section, you can check which version of WSL you're using with:

wsl.exe -l --verbose

Check WSL1 `$DISPLAY` variable

If you're running WSL1, the DISPLAY variable for WSL1 should simply be localhost:0.0 if this is the default distribution.

Check WSL2 `$DISPLAY` variable

Unfortunately for WSL2, it's a little more complicated for now, though I think they're planning on fixing this. You'll need something like this to extract the correct host:

export DISPLAY=$(grep -m 1 nameserver /etc/resolv.conf | awk '{print $2}'):0.0

Firewall Rules

Then you need to worry about the firewall. WSL comes up as a public network, but I wouldn't recommend allowing all public network traffic to access your X server. So instead, you can go ahead and select defaults when this sort of prompt comes up:

Now, irritatingly this will actively add a block rule (rather than simply not add an allow rule) for public networks which you will need to disable for the next step by going into Windows Defender Firewall -> Inbound Rules and disabling this block rule for TCP on the Public Network.

If you don't do the above step, the Block rule will take precedence over the Allow allow rule and you won't get through.

Now, right click on Inbound Rules and select New Rule..., select TCP port 6000 (most likely) and select defaults. This will open up your public network for this port... which is also not what you want. What you want is to only allow traffic from the WSL subnet. So refresh the list, scroll to your recently created name, right click and go to properties. Now under Scope, go to Remote IP address, Select These IP addresses and add in 172.16.0.0/12 to limit the subnets which can access this port to the WSL subnet. It should look something like this:

Alternatively you could just disable the entire firewall for WSL, but that adds a firewall warning that constantly irritates me:

powershell.exe -Command "Set-NetFirewallProfile -DisabledInterfaceAliases \"vEthernet (WSL)\""

Application X not working

Does the application use dbus? If so, it's recommended to put something like this in your .bashrc to satisfy the many applications which depend on dbus to function:

dbus_status=$(service dbus status)
if [[ $dbus_status = *"is not running"* ]]; then
  sudo service dbus --full-restart
fi

Also check that the .bashrc tweaks are added before any nastiness like this in your .bashrc which would prevent DISPLAY from being set:

# If not running interactively, don't do anything
[ -z "$PS1" ] && return

You can do similar with docker or any other service which you will need access to, but won't necessarily already be running in a vanilla WSL installation.

To debug further, you can run the shortcut directly from the command line from a cmd shell:

wsl.exe -d <your-wsl-distro> -u <your-wsl-user> -- source ~/.bashrc ; env; xterm

Replacing xterm with whatever command you're trying to launch. Note the env command will print out all environment variables set before running xterm in this example, so this should help you double check if DISPLAY is really set correctly.

Raising Issues

Issues may be raised in github issues. Before raising an issue though:

Verify that you have an X Server running on windows 10. Popular options include X410 or Xming.
Verify that you can actually launch X applications from a WSL terminal (e.g. try running xterm).

If an issue is to be required, please prepare the log output from the command and details on your execution environment. Ideally try and find the .desktop file relating to the failing software as well.

suikwasha/wsl-windows-toolbar-launcher