Unlocking Secure Authentication with Deno and JSON Web Tokens
What is Deno?
Deno is a modern, secure runtime for JavaScript and TypeScript that utilizes V8 and is built in Rust. Unlike Node.js, Deno boasts built-in support for TypeScript, ensuring security by default. Moreover, Deno leverages third-party packages with browser-compatible URLs to manage modules, eliminating the need for local caching.
Demystifying JSON Web Tokens
JSON Web Tokens (JWTs) are an internet standard for creating data with optional signatures and/or encryption, containing JSON payloads that assert various claims. In essence, JWTs are used for authentication. When a user logs into an application, the application generates a JWT and sends it back to the user. Most Deno use cases involving JWTs involve implementing authentication systems, requiring users to log in to access specific data.
Getting Started with JWT in Deno
To integrate JWT into our Deno application, we’ll utilize the djwt package. Prerequisites:
- Solid understanding of JavaScript
- A text editor (we’ll use VS Code)
- POSTMAN installed on your local machine
Setting Up the Project
Create a new directory for our application and inside it, create an index.ts file. We’ll write our code here. The djwt library doesn’t handle authentication or authorization; its sole purpose is to generate and validate valid JSON web tokens.
Importing the djwt Library
To use djwt, we need to import it into our application:
typescript
import { validateJwt, makeJwt, setExpiration, Payload, Jose } from 'https://deno.land/x/[email protected]/mod.ts';
The validateJwt method checks token validity, makeJwt generates a valid JWT, and setExpiration sets an expiration time for the token. Payload is a TypeScript interface for the JWT payload or data, while Jose indicates the algorithm and type of the token.
Generating a JSON Web Token
To work with JWT, we need to set a secret key, payload, and header. This is a basic JWT configuration. We’ll store these configs in a variable:
typescript
const config = {
secretKey: 'y_secret_key',
payload: {
name: 'John Doe',
},
header: {
alg: 'HS256',
typ: 'JWT',
},
};
The payloader method gets the payload as a parameter and sets the expiration data duration to 2021-01-01. We’ll return the payload object to use it in the makeJwt method.
Validating the JSON Web Token
We can use the imported validateJwt to check whether a token is valid or not. This method takes in the token, key, and algorithm as parameters. We’ll use the token received from the makeJwt method for testing.
Testing the Endpoint
Let’s test our endpoint using POSTMAN. Sending a post request to the /generate route and passing a name as a body will generate a token for that user.
Adding Authentication to Deno Applications
Integrating authentication into Deno applications is crucial for security. JWT is widely used across different technologies, making it an excellent choice for implementing authorization and authentication.