feat(exit-hook): new package (#22)

README.md

@@ -14,6 +14,7 @@ Here is a brief overview of the included libraries:
 8. [`nano-build`](./packages/nano-build/README.md): This is a tool for building/bundling ECMAScript, TypeScript, and JavaScript libraries. It's user-friendly, requires no setup, follows best practices, has no dependencies, and uses esbuild for improved performance.
 9. [`type-helper`](./packages/type-helper/README.md): Collection of useful typescript type helpers.
 10. [`wait`](./packages/wait/README.md): Comprehensive toolkit for managing asynchronous operations.
+11. [`exit-hook`](./packages/exit-hook/README.md): A utility for registering exit handlers in Node.js.
 <!-- 9. [`async-queue`](./packages/async-queue/README.md): This is a utility for managing asynchronous operations in a queue. -->
 
 For more detailed information and guidelines on how to use each package, please refer to to each package's README.

packages/exit-hook/README.md

@@ -0,0 +1,21 @@
+# Exit Hook
+
+A utility for registering exit handlers in Node.js.
+
+## Installation
+
+```bash
+yarn add @alwatr/exit-hook
+```
+
+## Usage
+
+```typescript
+import {exitHook} from '@alwatr/exit-hook';
+
+const saveAllData = () => {
+ // save all data
+};
+
+exitHook(saveAllData);
+```

packages/exit-hook/package.json

@@ -0,0 +1,74 @@
+{
+ "name": "@alwatr/exit-hook",
+ "version": "0.0.0",
+ "description": "A utility for registering exit handlers in Node.js.",
+ "author": "S. Ali Mihandoost <[email protected]>",
+ "keywords": [
+ "exit-hook",
+ "hook",
+ "exit",
+ "cross-platform",
+ "ECMAScript",
+ "typescript",
+ "javascript",
+ "node",
+ "nodejs",
+ "esm",
+ "module",
+ "utility",
+ "util",
+ "utils",
+ "nanolib",
+ "alwatr"
+ ],
+ "type": "module",
+ "main": "./dist/main.cjs",
+ "module": "./dist/main.mjs",
+ "types": "./dist/main.d.ts",
+ "exports": {
+ ".": {
+ "import": "./dist/main.mjs",
+ "require": "./dist/main.cjs",
+ "types": "./dist/main.d.ts"
+ }
+ },
+ "license": "MIT",
+ "files": [
+ "**/*.{js,mjs,cjs,map,d.ts,html,md}",
+ "!demo/**/*"
+ ],
+ "publishConfig": {
+ "access": "public"
+ },
+ "repository": {
+ "type": "git",
+ "url": "https:/Alwatr/nanolib",
+ "directory": "packages/exit-hook"
+ },
+ "homepage": "https:/Alwatr/nanolib/tree/next/packages/exit-hook#readme",
+ "bugs": {
+ "url": "https:/Alwatr/nanolib/issues"
+ },
+ "prettier": "@alwatr/prettier-config",
+ "scripts": {
+ "b": "yarn run build",
+ "w": "yarn run watch",
+ "c": "yarn run clean",
+ "cb": "yarn run clean && yarn run build",
+ "d": "yarn run build:es && ALWATR_DEBUG=1 yarn node",
+ "build": "yarn run build:ts & yarn run build:es",
+ "build:es": "nano-build --preset=module",
+ "build:ts": "tsc --build",
+ "watch": "yarn run watch:ts & yarn run watch:es",
+ "watch:es": "yarn run build:es --watch",
+ "watch:ts": "yarn run build:ts --watch --preserveWatchOutput",
+ "clean": "rm -rfv dist *.tsbuildinfo"
+ },
+ "devDependencies": {
+ "@alwatr/nano-build": "workspace:^",
+ "@alwatr/prettier-config": "workspace:^",
+ "@alwatr/tsconfig-base": "workspace:^",
+ "@types/node": "^20.10.6",
+ "typescript": "^5.3.3"
+ }
+}

packages/exit-hook/src/main.ts

@@ -0,0 +1,76 @@
+/**
+ * Array of callback functions to be called when the process is exiting.
+ */
+const callbacks: (() => void)[] = [];
+
+/**
+ * True whether the process is exiting to prevent calling the callbacks more than once.
+ */
+let exiting = false;
+
+/**
+ * Add a callback function to be called when the process is exiting.
+ *
+ * @param callback The callback function to be called when the process is exiting.
+ *
+ * @example
+ * ```typescript
+ * const saveAllData = () => {
+ * // save all data
+ * };
+ *
+ * existHook(saveAllData);
+ * ```
+ */
+export function existHook(callback: () => void): void {
+ callbacks.push(callback);
+}
+
+/**
+ * A once callback to be called on process exit event.
+ */
+function onExit_() {
+ if (exiting === true) return;
+ exiting = true;
+
+ for (const callback of callbacks) {
+ try {
+ callback();
+ }
+ catch (error) {
+ console.error('Error in exit hook callback:', error);
+ }
+ }
+}
+
+/**
+ * This event emitted when Node.js empties its event loop and has no additional work to schedule.
+ * Normally, the Node.js process will exit when there is no work scheduled,
+ * but a listener registered on the 'beforeExit' event can make asynchronous calls, and thereby cause the Node.js process to continue.
+ *
+ * @see https://nodejs.org/api/process.html#event-beforeexit
+ */
+process.once('beforeExit', onExit_);
+
+/**
+ * This event is emitted when the Node.js process is about to exit as a result of either:
+ * 1- The `process.exit()` method being called explicitly.
+ * 2- The Node.js event loop no longer having any additional work to perform.
+ *
+ * @see https://nodejs.org/api/process.html#event-exit
+ */
+process.once('exit', onExit_);
+
+/**
+ * This event is emitted in terminal mode before exiting with code 128 + signal number.
+ *
+ * @see https://nodejs.org/api/process.html#signal-events
+ */
+process.once('SIGTERM', onExit_);
+
+/**
+ * This event is emitted when `Ctrl+C` is pressed.
+ *
+ * @see https://nodejs.org/api/process.html#signal-events
+ */
+process.once('SIGINT', onExit_);

packages/exit-hook/tsconfig.json

@@ -0,0 +1,10 @@
+{
+ "extends": "@alwatr/tsconfig-base/tsconfig.json",
+ "compilerOptions": {
+ "rootDir": "src",
+ "outDir": "dist",
+ "emitDeclarationOnly": true,
+ "composite": true,
+ },
+ "include": ["src/**/*.ts"]
+}

yarn.lock

@@ -45,6 +45,18 @@ __metadata:
  languageName: unknown
  linkType: soft
 
+"@alwatr/exit-hook@workspace:packages/exit-hook":
+ version: 0.0.0-use.local
+ resolution: "@alwatr/exit-hook@workspace:packages/exit-hook"
+ dependencies:
+ "@alwatr/nano-build": "workspace:^"
+ "@alwatr/prettier-config": "workspace:^"
+ "@alwatr/tsconfig-base": "workspace:^"
+ "@types/node": "npm:^20.10.6"
+ typescript: "npm:^5.3.3"
+ languageName: unknown
+ linkType: soft
+
 "@alwatr/flat-string@workspace:packages/flat-string":
  version: 0.0.0-use.local
  resolution: "@alwatr/flat-string@workspace:packages/flat-string"