refactor(updatenotification): replace pm2 usage with node logic (#4134)

We can rely on PM2's native restart-on-exit behavior instead of the
programmatic pm2 API.

Fixes
https://github.com/MagicMirrorOrg/MagicMirror/security/dependabot/82 by
removing pm2.

Note: Originally this PR was intended to update pm2, but after
discussion, we decided to replace it instead. See the discussion below.

defaultmodules/updatenotification/node_helper.js

@@ -49,7 +49,6 @@ module.exports = NodeHelper.create({
 			case "CONFIG":
 				this.config = payload;
 				this.updateHelper = new UpdateHelper(this.config);
-				await this.updateHelper.check_PM2_Process();
 				break;
 			case "MODULES":
 				// if this is the 1st time thru the update check process

defaultmodules/updatenotification/update_helper.js

@@ -1,6 +1,5 @@
 const Exec = require("node:child_process").exec;
 const Spawn = require("node:child_process").spawn;
-const fs = require("node:fs");
 
 const Log = require("logger");
 
@@ -47,8 +46,6 @@ class Updater {
 		this.autoRestart = config.updateAutorestart;
 		this.moduleList = {};
 		this.updating = false;
-		this.usePM2 = false; // don't use pm2 by default
-		this.PM2Id = null; // pm2 process number
 		this.version = global.version;
 		this.root_path = global.root_path;
 		Log.info("Updater Class Loaded!");
@@ -122,7 +119,7 @@ class Updater {
 					Result.updated = true;
 					if (this.autoRestart) {
 						Log.info("Update done");
-						setTimeout(() => this.restart(), 3000);
+						setTimeout(() => this.nodeRestart(), 3000);
 					} else {
 						Log.info("Update done, don't forget to restart MagicMirror!");
 						Result.needRestart = true;
@@ -133,23 +130,6 @@ class Updater {
 		});
 	}
 
-	// restart rules (pm2 or node --run start)
-	restart () {
-		if (this.usePM2) this.pm2Restart();
-		else this.nodeRestart();
-	}
-
-	// restart MagicMirror with "pm2": use PM2Id for restart it
-	pm2Restart () {
-		Log.info("[PM2] restarting MagicMirror...");
-		const pm2 = require("pm2");
-		pm2.restart(this.PM2Id, (err) => {
-			if (err) {
-				Log.error("[PM2] restart Error", err);
-			}
-		});
-	}
-
 	// restart MagicMirror with "node --run start"
 	nodeRestart () {
 		Log.info("Restarting MagicMirror...");
@@ -160,58 +140,6 @@ class Updater {
 		process.exit();
 	}
 
-	// Check using pm2
-	check_PM2_Process () {
-		Log.info("Checking PM2 using...");
-		return new Promise((resolve) => {
-			if (fs.existsSync("/.dockerenv")) {
-				Log.info("[PM2] Running in docker container, not using PM2 ...");
-				resolve(false);
-				return;
-			}
-
-			if (process.env.unique_id === undefined) {
-				Log.info("[PM2] You are not using pm2");
-				resolve(false);
-				return;
-			}
-
-			Log.debug(`[PM2] Search for pm2 id: ${process.env.pm_id} -- name: ${process.env.name} -- unique_id: ${process.env.unique_id}`);
-
-			const pm2 = require("pm2");
-			pm2.connect((err) => {
-				if (err) {
-					Log.error("[PM2]", err);
-					resolve(false);
-					return;
-				}
-				pm2.list((err, list) => {
-					if (err) {
-						Log.error("[PM2] Can't get process List!");
-						resolve(false);
-						return;
-					}
-					list.forEach((pm) => {
-						Log.debug(`[PM2] found pm2 process id: ${pm.pm_id} -- name: ${pm.name} -- unique_id: ${pm.pm2_env.unique_id}`);
-						if (pm.pm2_env.status === "online" && process.env.name === pm.name && +process.env.pm_id === +pm.pm_id && process.env.unique_id === pm.pm2_env.unique_id) {
-							this.PM2Id = pm.pm_id;
-							this.usePM2 = true;
-							Log.info(`[PM2] You are using pm2 with id: ${this.PM2Id} (${pm.name})`);
-							resolve(true);
-						} else {
-							Log.debug(`[PM2] pm2 process id: ${pm.pm_id} don't match...`);
-						}
-					});
-					pm2.disconnect();
-					if (!this.usePM2) {
-						Log.info("[PM2] You are not using pm2");
-						resolve(false);
-					}
-				});
-			});
-		});
-	}
-
 	// check if module is MagicMirror
 	isMagicMirror (module) {
 		if (module === "MagicMirror") return true;

package.json

@@ -105,7 +105,6 @@
 		"moment-timezone": "^0.6.2",
 		"node-ical": "^0.26.0",
 		"nunjucks": "^3.2.4",
-		"pm2": "^6.0.14",
 		"socket.io": "^4.8.3",
 		"suncalc": "^1.9.0",
 		"systeminformation": "^5.31.5",

tests/unit/functions/update_helper_spec.js

@@ -0,0 +1,90 @@
+import { mkdtempSync, mkdirSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+describe("UpdateHelper", () => {
+	const originalEnv = { ...process.env };
+	const tempRoots = [];
+
+	beforeEach(() => {
+		vi.resetModules();
+		process.env = { ...originalEnv };
+		global.version = "test";
+		global.root_path = process.cwd();
+	});
+
+	afterEach(() => {
+		process.env = originalEnv;
+		vi.useRealTimers();
+		vi.restoreAllMocks();
+		for (const tempRoot of tempRoots) {
+			rmSync(tempRoot, { recursive: true, force: true });
+		}
+		tempRoots.length = 0;
+	});
+
+	/**
+	 * Creates a temporary MagicMirror-like root with a module directory.
+	 * @param {string} moduleName - Name of the module directory to create.
+	 * @returns {{ root: string, modulePath: string }} Created paths.
+	 */
+	function createTempModuleRoot (moduleName) {
+		const root = mkdtempSync(join(tmpdir(), "mm-updater-"));
+		const modulePath = join(root, "modules", moduleName);
+		mkdirSync(modulePath, { recursive: true });
+		tempRoots.push(root);
+		return { root, modulePath };
+	}
+
+	/**
+	 * Creates a fresh UpdateHelper instance for testing.
+	 * @param {object} config - Optional config overrides.
+	 * @returns {Promise<object>} Resolved UpdateHelper instance.
+	 */
+	async function createUpdater (config = {}) {
+		const updateHelperModule = await import("../../../defaultmodules/updatenotification/update_helper");
+		const UpdateHelper = updateHelperModule.default || updateHelperModule;
+		return new UpdateHelper({ updates: [], updateTimeout: 1000, updateAutorestart: false, ...config });
+	}
+
+	it("marks update as requiring manual restart when autoRestart is disabled", async () => {
+		const moduleName = "MMM-Test";
+		const { root } = createTempModuleRoot(moduleName);
+		global.root_path = root;
+
+		const updater = await createUpdater({ updateAutorestart: false });
+		const result = await updater.updateProcess({
+			name: moduleName,
+			updateCommand: `"${process.execPath}" -p 1`
+		});
+
+		expect(result.error).toBe(false);
+		expect(result.updated).toBe(true);
+		expect(result.needRestart).toBe(true);
+	});
+
+	it("schedules node restart when autoRestart is enabled", async () => {
+		vi.useFakeTimers();
+
+		const moduleName = "MMM-Test";
+		const { root } = createTempModuleRoot(moduleName);
+		global.root_path = root;
+
+		const updater = await createUpdater({ updateAutorestart: true });
+		const nodeRestartSpy = vi.spyOn(updater, "nodeRestart").mockImplementation(() => {});
+
+		const result = await updater.updateProcess({
+			name: moduleName,
+			updateCommand: `"${process.execPath}" -p 1`
+		});
+
+		expect(result.error).toBe(false);
+		expect(result.updated).toBe(true);
+		expect(result.needRestart).toBe(false);
+		expect(nodeRestartSpy).not.toHaveBeenCalled();
+
+		vi.advanceTimersByTime(3000);
+		expect(nodeRestartSpy).toHaveBeenCalledTimes(1);
+	});
+});