Integrate lua-language-server (LuaLS) with Monaco editor in Electron app

build-scripts/download-lua-ls.js

@@ -0,0 +1,199 @@
+#!/usr/bin/env node
+/**
+ * Downloads the appropriate lua-language-server binary for the current
+ * (or target) platform and extracts it into resources/lua-language-server/.
+ *
+ * Usage:
+ *   node build-scripts/download-lua-ls.js
+ *   node build-scripts/download-lua-ls.js --version 3.13.6
+ *   node build-scripts/download-lua-ls.js --platform win32 --arch x64
+ *
+ * The script is intentionally self-contained (no extra npm deps beyond
+ * Node built-ins + node-fetch which is already a project dependency).
+ */
+
+"use strict";
+
+const https = require("https");
+const http = require("http");
+const fs = require("fs");
+const path = require("path");
+const os = require("os");
+const { execSync } = require("child_process");
+
+// ── Configuration ────────────────────────────────────────────────────────────
+
+const LUA_LS_VERSION =
+  parseArg("--version") || process.env.LUA_LS_VERSION || "3.13.6";
+
+const platform = parseArg("--platform") || process.platform; // win32 | darwin | linux
+const arch = parseArg("--arch") || process.arch; // x64 | arm64
+
+const OUTPUT_DIR = path.resolve(
+  __dirname,
+  "..",
+  "resources",
+  "lua-language-server",
+);
+
+// ── Platform → asset name mapping ───────────────────────────────────────────
+
+/** Maps Node.js platform/arch to the GitHub release asset suffix. */
+function getAssetName(platform, arch, version) {
+  const platformMap = {
+    win32: { x64: `win32-x64` },
+    darwin: { x64: `darwin-x64`, arm64: `darwin-arm64` },
+    linux: { x64: `linux-x64` },
+  };
+
+  const key = (platformMap[platform] || {})[arch];
+  if (!key) {
+    throw new Error(
+      `Unsupported platform/arch combination: ${platform}/${arch}`,
+    );
+  }
+
+  const ext = platform === "win32" ? "zip" : "tar.gz";
+  return `lua-language-server-${version}-${key}.${ext}`;
+}
+
+/** Returns the download URL for the given version and asset name. */
+function getDownloadUrl(version, assetName) {
+  return `https://github.com/LuaLS/lua-language-server/releases/download/${version}/${assetName}`;
+}
+
+// ── Helpers ──────────────────────────────────────────────────────────────────
+
+function parseArg(name) {
+  const idx = process.argv.indexOf(name);
+  return idx !== -1 ? process.argv[idx + 1] : null;
+}
+
+function mkdirp(dir) {
+  fs.mkdirSync(dir, { recursive: true });
+}
+
+/** Follow HTTP redirects and return the final response. */
+function fetch(url) {
+  return new Promise((resolve, reject) => {
+    const protocol = url.startsWith("https") ? https : http;
+    protocol.get(url, (res) => {
+      if (res.statusCode === 301 || res.statusCode === 302) {
+        fetch(res.headers.location).then(resolve).catch(reject);
+      } else if (res.statusCode !== 200) {
+        reject(
+          new Error(
+            `HTTP ${res.statusCode} while downloading ${url}`,
+          ),
+        );
+      } else {
+        resolve(res);
+      }
+    }).on("error", reject);
+  });
+}
+
+/** Download url → destPath, showing a simple progress counter. */
+async function download(url, destPath) {
+  console.log(`  Downloading: ${url}`);
+  const res = await fetch(url);
+  const total = parseInt(res.headers["content-length"] || "0", 10);
+  let received = 0;
+
+  return new Promise((resolve, reject) => {
+    const out = fs.createWriteStream(destPath);
+    res.on("data", (chunk) => {
+      received += chunk.length;
+      if (total > 0) {
+        const pct = Math.round((received / total) * 100);
+        process.stdout.write(`\r  Progress: ${pct}%`);
+      }
+    });
+    res.pipe(out);
+    out.on("finish", () => {
+      process.stdout.write("\n");
+      resolve();
+    });
+    out.on("error", reject);
+    res.on("error", reject);
+  });
+}
+
+/** Extract a .tar.gz archive using the system tar command. */
+function extractTarGz(archivePath, destDir) {
+  mkdirp(destDir);
+  execSync(`tar -xzf "${archivePath}" -C "${destDir}"`);
+}
+
+/** Extract a .zip archive using the system unzip / PowerShell. */
+function extractZip(archivePath, destDir) {
+  mkdirp(destDir);
+  if (process.platform === "win32") {
+    execSync(
+      `powershell -Command "Expand-Archive -Force '${archivePath}' '${destDir}'"`,
+    );
+  } else {
+    execSync(`unzip -o "${archivePath}" -d "${destDir}"`);
+  }
+}
+
+// ── Main ─────────────────────────────────────────────────────────────────────
+
+async function main() {
+  console.log(
+    `\nlua-language-server downloader  (v${LUA_LS_VERSION}  ${platform}/${arch})\n`,
+  );
+
+  const assetName = getAssetName(platform, arch, LUA_LS_VERSION);
+  const url = getDownloadUrl(LUA_LS_VERSION, assetName);
+
+  // Check if already present
+  const binaryName =
+    platform === "win32"
+      ? "lua-language-server.exe"
+      : "lua-language-server";
+  const binaryPath = path.join(OUTPUT_DIR, "bin", binaryName);
+
+  if (fs.existsSync(binaryPath)) {
+    console.log(`  Already installed: ${binaryPath}`);
+    console.log("  Delete resources/lua-language-server/ to force re-download.");
+    return;
+  }
+
+  // Download
+  const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), "lua-ls-"));
+  const archivePath = path.join(tmpDir, assetName);
+
+  try {
+    await download(url, archivePath);
+
+    // Extract into OUTPUT_DIR
+    console.log(`  Extracting to: ${OUTPUT_DIR}`);
+    if (archivePath.endsWith(".tar.gz")) {
+      extractTarGz(archivePath, OUTPUT_DIR);
+    } else {
+      extractZip(archivePath, OUTPUT_DIR);
+    }
+
+    if (!fs.existsSync(binaryPath)) {
+      throw new Error(
+        `Extraction succeeded but binary not found at: ${binaryPath}`,
+      );
+    }
+
+    // Make executable on POSIX
+    if (platform !== "win32") {
+      fs.chmodSync(binaryPath, 0o755);
+    }
+
+    console.log(`  ✓ lua-language-server ready: ${binaryPath}`);
+  } finally {
+    // Clean up temp dir
+    fs.rmSync(tmpDir, { recursive: true, force: true });
+  }
+}
+
+main().catch((err) => {
+  console.error("\n✗ Failed to download lua-language-server:", err.message);
+  process.exit(1);
+});

electron-builder-config.js

@@ -32,6 +32,15 @@ const config = {
       from: "src/renderer/assets/**/*",
       to: "assets",
     },
+    {
+      // lua-language-server binary — downloaded by `node build-scripts/download-lua-ls.js`
+      // before running electron-builder. The directory is only included when it exists
+      // (i.e. the download script has been run); builds without it still work but LuaLS
+      // features will be unavailable at runtime.
+      from: "resources/lua-language-server",
+      to: "lua-language-server",
+      filter: ["**/*"],
+    },
   ],
   files: ["**/*"],
   win: {

package.json

@@ -78,13 +78,14 @@
     "yauzl": "^3.2.0"
   },
   "scripts": {
+    "download-lua-ls": "node build-scripts/download-lua-ls.js",
     "e:builder": "cross-env VITE_BUILD_TARGET=electron NOTARIZE=true electron-builder --config electron-builder-config.js --publish onTagOrDraft",
     "e:builder:nightly": "cross-env VITE_BUILD_ENV=nightly VITE_BUILD_TARGET=electron NOTARIZE=true DEBUG=electron-notarize* electron-builder --config electron-builder-config.js --publish never",
     "e:builder:local": "cross-env VITE_BUILD_ENV=nightly VITE_BUILD_TARGET=electron DEBUG=electron-builder DEBUG=electron-notarize* electron-builder --config electron-builder-config.js --publish never",
-    "export": "cross-env VITE_BUILD_ENV=production run-s s:build e:builder",
-    "export:nightly": "run-s s:build e:builder:nightly",
-    "export:alpha": "cross-env VITE_BUILD_ENV=alpha run-s s:build e:builder",
-    "export:local": "run-s clean-up s:build e:builder:local",
+    "export": "cross-env VITE_BUILD_ENV=production run-s download-lua-ls s:build e:builder",
+    "export:nightly": "run-s download-lua-ls s:build e:builder:nightly",
+    "export:alpha": "cross-env VITE_BUILD_ENV=alpha run-s download-lua-ls s:build e:builder",
+    "export:local": "run-s clean-up download-lua-ls s:build e:builder:local",
     "clean-up": "rm -rf dist && rm -rf dist-web && rm -rf build",
     "rebuild": "./node_modules/.bin/electron-rebuild.cmd",
     "s:build": "electron-vite build",

src/electron/main.ts

@@ -86,6 +86,7 @@ import {
 } from "./src/profiles";
 import { fetchReleaseNotes, fetchUrlJSON } from "./src/fetch";
 import { getLatestVideo } from "./src/youtube";
+import { getLuaLanguageServer } from "./src/lua-language-server";
 
 log.info("App starting...");
 log.info("BUILD ENVS:", import.meta.env);
@@ -94,6 +95,9 @@ log.info("BUILD ENVS:", import.meta.env);
 // be closed automatically when the JavaScript object is garbage collected.
 let mainWindow;
 
+// LuaLS WebSocket proxy port (0 = not started / binary not found)
+let luaLsPort = 0;
+
 // Bootloader detection service state
 let bootloaderDetectionTimeout: NodeJS.Timeout | null = null;
 let bootloaderDetectionRunning = false;
@@ -356,6 +360,28 @@ if (!gotTheLock) {
       create_tray();
     }
     createWindow();
+
+    // Start the LuaLS proxy server. The port is exposed to the renderer via
+    // the "getLuaLsPort" IPC channel (see preload.ts).
+    const annotationsDir = path.resolve(
+      __dirname,
+      "..",
+      "..",
+      "renderer",
+      "assets",
+      "lua",
+      "annotations",
+    );
+    getLuaLanguageServer()
+      .start({ annotationsDir })
+      .then((port) => {
+        luaLsPort = port;
+        log.info(`[LuaLS] Proxy started on port ${port}`);
+      })
+      .catch((err) => {
+        log.warn("[LuaLS] Failed to start proxy:", err);
+      });
+
     protocol.handle("package", (req) => {
       let requestPath = req.url.substring("package://".length);
 
@@ -1001,6 +1027,10 @@ ipcMain.on("get-app-path", (event) => {
   event.returnValue = app.getAppPath();
 });
 
+ipcMain.on("getLuaLsPort", (event) => {
+  event.returnValue = luaLsPort;
+});
+
 ipcMain.on("analytics_uuid", (event) => {
   event.returnValue = store.get("userId");
 });
@@ -1085,4 +1115,5 @@ app.on("activate", () => {
 app.on("before-quit", (evt) => {
   log.info("before-quit evt", evt);
   app.quitting = true;
+  getLuaLanguageServer().stop();
 });

src/electron/preload.ts

@@ -113,6 +113,9 @@ contextBridge.exposeInMainWorld("electron", {
   appLoaded: () => appLoadedPromiseResolve(undefined),
   showQuitDialog: (callback) => ipcRenderer.on("showQuitDialog", callback),
   quitDialogResult: (result) => ipcRenderer.send("quitDialogResult", result),
+  luaLanguageServer: {
+    getPort: () => ipcRenderer.sendSync("getLuaLsPort") as number,
+  },
 });
 
 let appLoadedPromiseResolve: (any) => any;