One-click launch setup

1. Save this as openjk-url.ps1 (edit the $GameExe path to your client):

param([string]$Url)
# EDIT: full path to your JKA multiplayer client (TaystJK / OpenJK / EternalJK):
$GameExe = "C:\Games\TaystJK\eternaljk.x86_64.exe"

# openjk://<host>:<port>[/<code>] — strict validation is the security boundary.
if ($Url -notmatch '^openjk://([A-Za-z0-9.-]{1,253}):([0-9]{1,5})(?:/([A-Za-z0-9]{1,32}))?/?$') { exit 1 }
$h = $Matches[1]; $p = $Matches[2]; $code = $Matches[3]
$gameArgs = @()
if ($code) { $gameArgs += @('+set','password',$code) }
$gameArgs += @('+connect', "${h}:${p}")
Start-Process -FilePath $GameExe -ArgumentList $gameArgs

2. Save this as openjk.reg — edit the path to match where you put the .ps1 — then double-click it to import (no admin needed, it's per-user):

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Classes\openjk]
@="URL:OpenJK Protocol"
"URL Protocol"=""

[HKEY_CURRENT_USER\Software\Classes\openjk\shell\open\command]
@="powershell -NoProfile -ExecutionPolicy Bypass -File \"C:\\Games\\TaystJK\\openjk-url.ps1\" \"%1\""

3. Click a Launch in game button and allow the browser prompt. Done.

1. Save as ~/.local/bin/openjk-url.sh (edit GAME), then chmod +x it:

#!/usr/bin/env bash
# EDIT: path to your JKA multiplayer client binary (or set $OPENJK_GAME):
GAME="${OPENJK_GAME:-$HOME/games/TaystJK/eternaljk.x86_64}"

url="$1"
# openjk://<host>:<port>[/<code>] — strict validation is the security boundary.
re='^openjk://([A-Za-z0-9.-]{1,253}):([0-9]{1,5})(/([A-Za-z0-9]{1,32}))?/?$'
[[ "$url" =~ $re ]] || { command -v notify-send >/dev/null && notify-send "OpenJK" "Invalid link"; exit 1; }
host="${BASH_REMATCH[1]}"; port="${BASH_REMATCH[2]}"; code="${BASH_REMATCH[4]}"
if [[ -n "$code" ]]; then exec "$GAME" +set password "$code" +connect "$host:$port"
else exec "$GAME" +connect "$host:$port"; fi

2. Save as ~/.local/share/applications/openjk.desktop (edit the Exec path):

[Desktop Entry]
Type=Application
Name=OpenJK URL Handler
Exec=/home/YOUR_USER/.local/bin/openjk-url.sh %u
MimeType=x-scheme-handler/openjk;
NoDisplay=true

3. Register it:

xdg-mime default openjk.desktop x-scheme-handler/openjk
update-desktop-database ~/.local/share/applications

1. Open Script Editor, paste this (edit gameExe), and Export as an Application named e.g. OpenJK URL.app:

-- EDIT: path to your client binary inside the .app (or a standalone binary):
property gameExe : "/Applications/TaystJK.app/Contents/MacOS/eternaljk"

on open location this_URL
	-- strict validation is the security boundary
	set ok to do shell script "echo " & quoted form of this_URL & " | grep -Eq '^openjk://[A-Za-z0-9.-]{1,253}:[0-9]{1,5}(/[A-Za-z0-9]{1,32})?/?$' && echo ok || true"
	if ok is not "ok" then return
	set body to text 10 thru -1 of this_URL -- drop 'openjk://'
	set AppleScript's text item delimiters to "/"
	set parts to text items of body
	set hostport to item 1 of parts
	set theCode to ""
	if (count of parts) is greater than 1 then set theCode to item 2 of parts
	set AppleScript's text item delimiters to ""
	if theCode is not "" then
		do shell script quoted form of gameExe & " +set password " & quoted form of theCode & " +connect " & quoted form of hostport & " > /dev/null 2>&1 &"
	else
		do shell script quoted form of gameExe & " +connect " & quoted form of hostport & " > /dev/null 2>&1 &"
	end if
end open location

2. Add this to the app's Info.plist (right-click the .app → Show Package Contents → Contents/Info.plist), inside the top-level <dict>:

<key>CFBundleURLTypes</key>
<array><dict>
  <key>CFBundleURLName</key><string>pro.playja.openjk</string>
  <key>CFBundleURLSchemes</key><array><string>openjk</string></array>
</dict></array>

3. Launch the app once so macOS registers the scheme, then use the buttons.