basic typescript migration

Author: Keimeno

express-main-example/.gitignore

@@ -1,2 +1,3 @@
 node_modules
 *.sqlite
+dist

express-main-example/express/routes/instruments.js

@@ -1,20 +1,26 @@
 {
-  "name": "express-main-example",
-  "version": "0.0.0",
-  "description": "This is an example of how to setup Sequelize and Express together in a project for NodeJS 10 and above.",
-  "main": "index.js",
-  "scripts": {
-    "start": "node index.js",
-    "setup-example-db": "node sqlite-example-database/setup.js"
-  },
-  "engines": {
-    "node": ">=10"
-  },
-  "license": "MIT",
-  "dependencies": {
-    "body-parser": "^1.19.0",
-    "express": "^4.17.1",
-    "sequelize": "^6.3.3",
-    "sqlite3": "^5.0.0"
-  }
+	"name": "express-main-example",
+	"version": "0.0.0",
+	"description": "This is an example of how to setup Sequelize and Express together in a project for NodeJS 10 and above.",
+	"main": "index.js",
+	"scripts": {
+		"start": "tsc-watch --onSuccess \"node dist/index.js\"",
+		"setup-example-db": "tsc && node dist/sqlite-example-database/setup.js"
+	},
+	"engines": {
+		"node": ">=10"
+	},
+	"license": "MIT",
+	"dependencies": {
+		"body-parser": "^1.19.0",
+		"express": "^4.17.1",
+		"sequelize": "^6.3.3",
+		"sqlite3": "^5.0.0"
+	},
+	"devDependencies": {
+		"@types/body-parser": "^1.19.0",
+		"@types/express": "^4.17.11",
+		"tsc-watch": "^4.2.9",
+		"typescript": "^4.2.3"
+	}
 }

express-main-example/express/routes/orchestras.js

@@ -1,22 +1,28 @@
-const express = require('express');
-const bodyParser = require('body-parser');
+import express, { NextFunction, Request, Response } from "express";
+import { json, urlencoded } from "body-parser";
 
 const routes = {
-	users: require('./routes/users'),
-	instruments: require('./routes/instruments'),
-	orchestras: require('./routes/orchestras'),
+	users: require("./routes/users"),
+	instruments: require("./routes/instruments"),
+	orchestras: require("./routes/orchestras"),
 	// Add more routes here...
 	// items: require('./routes/items'),
 };
 
 const app = express();
 
-app.use(bodyParser.json());
-app.use(bodyParser.urlencoded({ extended: true }));
+app.use(json());
+app.use(urlencoded({ extended: true }));
+
+type Handler = (
+	req?: Request,
+	res?: Response,
+	next?: NextFunction
+) => Promise<void> | void;
 
 // We create a wrapper to workaround async errors not being transmitted correctly.
-function makeHandlerAwareOfAsyncErrors(handler) {
-	return async function(req, res, next) {
+function makeHandlerAwareOfAsyncErrors(handler: Handler) {
+	return async function (req: Request, res: Response, next: NextFunction) {
 		try {
 			await handler(req, res);
 		} catch (error) {
@@ -26,7 +32,7 @@ function makeHandlerAwareOfAsyncErrors(handler) {
 }
 
 // We provide a root route just as an example
-app.get('/', (req, res) => {
+app.get("/", (req: Request, res: Response) => {
 	res.send(`
 		<h2>Hello, Sequelize + Express!</h2>
 		<p>Make sure you have executed <b>npm run setup-example-db</b> once to have a populated example database. Otherwise, you will get <i>'no such table'</i> errors.</p>
@@ -69,4 +75,4 @@ for (const [routeName, routeController] of Object.entries(routes)) {
 	}
 }
 
-module.exports = app;
+export default app;

express-main-example/express/routes/users.js

@@ -1,11 +1,11 @@
+import { Request } from "express";
+
 // A helper function to assert the request ID param is valid
 // and convert it to a number (since it comes as a string by default)
-function getIdParam(req) {
+export function getIdParam(req: Request) {
 	const id = req.params.id;
 	if (/^\d+$/.test(id)) {
 		return Number.parseInt(id, 10);
 	}
 	throw new TypeError(`Invalid ':id' param: "${id}"`);
 }
-
-module.exports = { getIdParam };