Why won't node.js kill the process?

Question

Node.js

Why doesn't node.js kill the process on the port when I get an error and it stays there? Or I want to restart the server, I press trl + c in the terminal, then I start it again and it says to me that the port is already busy?

Here is my server on ts

import express, { Application } from 'express';
import path from 'path';
import * as dotenv from 'dotenv';
dotenv.config();

import router from './routes/index';
import errorrHandler from './middlewares/ErrorHandlingMiddleware';
import img from './models/imgModel';
import db from './db';

const PORT = process.env.PORT || 5000;

const app: Application = express();

// middlewares
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(express.static(path.resolve(__dirname, 'static')));

app.use('/', router);

app.use(errorrHandler);

async function start() {
  try {
    await db.authenticate();
    await db.sync();
    app.listen(PORT, () => console.log(`Server started on port ${PORT}`));
  } catch (err) {
    console.log(err);
  }
}

start();

Here is the json

{
  "name": "test-task-by-komah-ihor",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "node dist/app.js",
    "dev": "nodemon src/app.ts",
    "build": "tsc -p .",
    "lint": "eslint . --ext .ts"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@types/sharp": "^0.28.4",
    "axios": "^0.21.1",
    "cors": "^2.8.5",
    "del": "^6.0.0",
    "dotenv": "^10.0.0",
    "express": "^4.17.1",
    "lokijs": "^1.5.12",
    "multer": "^1.4.2",
    "pg": "^8.6.0",
    "pg-hstore": "^2.3.4",
    "reflect-metadata": "^0.1.13",
    "sequelize": "^6.6.5",
    "sequelize-typescript": "^2.1.0",
    "sharp": "^0.28.3",
    "sqlite": "^4.0.23"
  },
  "devDependencies": {
    "@types/bluebird": "^3.5.36",
    "@types/del": "^4.0.0",
    "@types/express": "^4.17.13",
    "@types/lokijs": "^1.5.5",
    "@types/multer": "^1.4.7",
    "@types/node": "^16.0.1",
    "@types/sequelize": "^4.28.10",
    "@types/validator": "^13.6.3",
    "@typescript-eslint/eslint-plugin": "^4.28.2",
    "@typescript-eslint/parser": "^4.28.2",
    "eslint": "^7.30.0",
    "eslint-config-airbnb-typescript": "^12.3.1",
    "eslint-plugin-import": "^2.23.4",
    "nodemon": "^2.0.9",
    "sequelize-cli": "^6.2.0",
    "ts-node": "^10.0.0",
    "typescript": "^4.3.5"
  }
}

Here is typescript config

{
  "compilerOptions": {
    /* Visit https://aka.ms/tsconfig.json to read more about this file */

    /* Basic Options */
    // "incremental": true,                         /* Enable incremental compilation */
    "target": "es6",                                /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', 'ES2021', or 'ESNEXT'. */
    "module": "commonjs",                           /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */
    // "lib": [],                                   /* Specify library files to be included in the compilation. */
    // "allowJs": true,                             /* Allow javascript files to be compiled. */
    // "checkJs": true,                             /* Report errors in .js files. */
    // "jsx": "preserve",                           /* Specify JSX code generation: 'preserve', 'react-native', 'react', 'react-jsx' or 'react-jsxdev'. */
    // "declaration": true,                         /* Generates corresponding '.d.ts' file. */
    // "declarationMap": true,                      /* Generates a sourcemap for each corresponding '.d.ts' file. */
    // "sourceMap": true,                           /* Generates corresponding '.map' file. */
    // "outFile": "./",                             /* Concatenate and emit output to single file. */
     "outDir": "./dist",                              /* Redirect output structure to the directory. */
     "rootDir": "./src",                             /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
    // "composite": true,                           /* Enable project compilation */
    // "tsBuildInfoFile": "./",                     /* Specify file to store incremental compilation information */
    // "removeComments": true,                      /* Do not emit comments to output. */
    // "noEmit": true,                              /* Do not emit outputs. */
    // "importHelpers": true,                       /* Import emit helpers from 'tslib'. */
    // "downlevelIteration": true,                  /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
    // "isolatedModules": true,                     /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
    /* Strict Type-Checking Options */
    "strict": true,                                 /* Enable all strict type-checking options. */
    // "noImplicitAny": true,                       /* Raise error on expressions and declarations with an implied 'any' type. */
    // "strictNullChecks": true,                    /* Enable strict null checks. */
    "noImplicitAny": false,
    // "strictFunctionTypes": true,                 /* Enable strict checking of function types. */
    // "strictBindCallApply": true,                 /* Enable strict 'bind', 'call', and 'apply' methods on functions. */
    // "strictPropertyInitialization": true,        /* Enable strict checking of property initialization in classes. */
    // "noImplicitThis": true,                      /* Raise error on 'this' expressions with an implied 'any' type. */
    // "alwaysStrict": true,                        /* Parse in strict mode and emit "use strict" for each source file. */

    /* Additional Checks */
    // "noUnusedLocals": true,                      /* Report errors on unused locals. */
    // "noUnusedParameters": true,                  /* Report errors on unused parameters. */
    // "noImplicitReturns": true,                   /* Report error when not all code paths in function return a value. */
    // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
    // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
    // "noImplicitOverride": true,                  /* Ensure overriding members in derived classes are marked with an 'override' modifier. */
    // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */

    /* Module Resolution Options */
     "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
    // "baseUrl": "./",                             /* Base directory to resolve non-absolute module names. */
    // "paths": {},                                 /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
    // "rootDirs": [],                              /* List of root folders whose combined content represents the structure of the project at runtime. */
    // "typeRoots": [],                             /* List of folders to include type definitions from. */
    // "types": [],                                 /* Type declaration files to be included in compilation. */
    // "allowSyntheticDefaultImports": true,        /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
    "esModuleInterop": true,                        /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
    // "preserveSymlinks": true,                    /* Do not resolve the real path of symlinks. */
    // "allowUmdGlobalAccess": true,                /* Allow accessing UMD globals from modules. */

    /* Source Map Options */
    // "sourceRoot": "",                            /* Specify the location where debugger should locate TypeScript files instead of source locations. */
    // "mapRoot": "",                               /* Specify the location where debugger should locate map files instead of generated locations. */
    // "inlineSourceMap": true,                     /* Emit a single file with source maps instead of having a separate file. */
    // "inlineSources": true,                       /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */

    /* Experimental Options */
    // "experimentalDecorators": true,              /* Enables experimental support for ES7 decorators. */
    // "emitDecoratorMetadata": true,               /* Enables experimental support for emitting type metadata for decorators. */

    /* Advanc ed Options */
    "skipLibCheck": true,                           /* Skip type checking of declaration files. */
    "forceConsistentCasingInFileNames": true        /* Disallow inconsistently-cased references to the same file. */
  }, 
  "exclude": ["node_modules"]
}

I also realized that the process dies only after some error in the code during nodemon pre-start

Answer 1

I think it's impossible to answer here without a concrete example. But if you want to kill a process, you can look at its PID and do kill - 9 PID. Then the process will be killed and the port closed