Passport.js is a flexible authentication middleware for Node.js. It can be used to authenticate users using a variety of strategies, including username and password, Facebook, Twitter, and more.
TypeScript is a superset of JavaScript that adds static type-checking and other features. TypeScript is widely used in large applications, and its support for modules, classes, and interfaces makes it a good choice for working with Passport.js.
In this article, we'll look at how to use TypeScript with Passport.js to build a user authentication system. We'll start by setting up a project with TypeScript and Express.js. Then we'll install Passport.js and configure it for use with TypeScript. Finally, we'll add some TypeScript code to implement a simple username and password authentication strategy.
To get started, we need to create a new TypeScript project. We'll use the Express.js web framework and the [TypeScript Node Starter](https://github.com/ Microsoft/TypeScript-Node-Starter) project template.
First, install the TypeScript compiler and the Express.js framework. We'll also need a few other modules:
npm install -g typescript
npm install express
npm install @types/express -D
Next, create a new project using the TypeScript Node Starter template:
npx tsc --init
This will create a tsconfig.json
file in your project. Open this file and add the following settings:
{
"compilerOptions": {
"target": "es6",
"module": "commonjs",
"outDir": "dist",
"strict": true
}
}
These settings will compile our TypeScript code to ES6 JavaScript, which is compatible with Express.js. The compiled code will be output to the dist
directory.
Now that we have a project set up, we can install Passport.js. Run the following command:
npm install passport
This will install the Passport.js module and add it to the package.json
file.
Passport.js uses a modular approach, with different "strategies" for authenticating users. There are strategies for authenticating with a username and password, with Facebook, with Twitter, and more. In this article, we'll focus on the username and password authentication strategy.
To use a Passport.js strategy, we need to install the corresponding module. For the username and password strategy, we'll use the passport-local module. Run the following command to install it:
npm install passport-local
Once the module is installed, we need to configure Passport.js to use it. We'll do this in the app.ts
file. First, we need to import the passport-local
module:
import passportLocal from "passport-local";
Next, we need to configure Passport.js to use the passport-local
strategy. We'll do this in the configurePassport
function:
function configurePassport(passport: passport.Passport) {
passport.use(new passportLocal.Strategy());
}
This configures Passport.js to use the passport-local
strategy. The passport-local
strategy authenticates users using a username and password.
Now that we have Passport.js configured, we can start implementing authentication. We'll do this in the app.ts
file.
First, we need to import the passport-local
module:
import passportLocal from "passport-local";
Next, we need to configure Passport.js to use the passport-local
strategy. We'll do this in the configurePassport
function:
function configurePassport(passport: passport.Passport) {
passport.use(new passportLocal.Strategy());
}
This configures Passport.js to use the passport-local
strategy. The passport-local
strategy authenticates users using a username and password.
Once we have Passport.js configured, we can write the code to authenticate a user. We'll do this in the login
function:
async function login(req: express.Request, res: express.Response) {
passport.authenticate("local", (err, user, info) => {
if (err) {
// Handle errors
}
if (!user) {
// Redirect to login page
}
// Login successful, redirect to home page
})(req, res);
}
This code authenticates a user using the passport-local
strategy. If the authentication is successful, the user will be redirected to the home page. Otherwise, they will be redirected to the login page.