Welcome on ExpressAPI !

ExpressAPI is a small, simple, and ultrafast library for building web APIs, built on Web Standards for Deno.

     

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✨ Features

• Minimal and intuitive API inspired by Express.js
• Built-in routing with support for all HTTP methods
• Middleware support
• Typed request and response objects
• Built-in file serving, redirection, and JSON handling
• Simple JWT-like token generation and verification
• Cryptographic helper utilities
• Secure random string generation

📦 Installation

deno add jsr:@webtools/expressapi

🧠 Usage Example

import { HttpMethods, HttpServer } from "jsr:@webtools/expressapi";

const server = new HttpServer(3000);

server.get("/hello", (req, res) => {
	return res.status(200).json({ message: "Hello, world!" });
});

server.post("/echo", (req, res) => {
	return res.json({ received: req.body });
});

🧱 Core Classes

HttpServer

Main entry point to create and start a web server.

Usage

const server = new HttpServer(5050);
server.get("/test", (req, res) => res.json({ success: true }));

Methods

• .get(url, handler, middlewares?)
• .post(url, handler, middlewares?)
• .put(url, handler, middlewares?)
• .patch(url, handler, middlewares?)
• .delete(url, handler, middlewares?)
• .use(middleware)
• .setEndpointNotFoundFunction(handler)

HttpRequest

Encapsulates the incoming HTTP request.

Properties

• .url: string
• .method: HttpMethods
• .headers: Headers
• .body: any (parsed JSON, text, form-data, etc.)
• .query: object with URL query parameters
• .params: object with URL path parameters
• .cookies: parsed cookie values
• .ip: client IP if available
• .raw: raw Request object

HttpResponse

Utility class to build and send responses.

Methods

• .status(code: number)
• .setHeader(name, value)
• .type(mime: string) — auto-detects MIME type
• .json(data: any) — sets JSON content type
• .sendFile(path: string) — serves local file
• .redirect(url: string, code = 307)
• .send(body: BodyInit | null)

HttpMethods

enum HttpMethods {
	GET = "GET",
	POST = "POST",
	PUT = "PUT",
	PATCH = "PATCH",
	DELETE = "DELETE",
}

Use this enum for routing and method comparisons.

🔐 Token & Security

JsonToken

A lightweight JWT-like utility to sign and verify JSON payloads using SHA-256 and a shared secret.

const jwt = new JsonToken("my-secret");

const token = await jwt.sign({ userId: 123 });
const data = await jwt.verify(token);

console.log(data); // { userId: 123 }

CryptoHelper

Cryptographic utility functions for hashing and randomness.

await CryptoHelper.sha256("password"); // SHA-256 hash
CryptoHelper.secureRandom(); // returns a cryptographically secure random float between 0 and 1

Available methods:

• .md5(payload)
• .sha256(payload)
• .sha512(payload)
• .secureRandom()

🔤 String Utilities

StringHelper

Random string generator based on pattern.

const key = StringHelper.generateRandomString("XXXX-XXXX", "ABC123");
console.log(key); // e.g., "1AC2-B3CA"

📚 API Overview

interface Route

interface Route {
	url: string;
	method: HttpMethods;
	middlewares: RequestListener[];
	requestListener: RequestListener;
}

type RequestListener

type RequestListener = (
	req: HttpRequest,
	res: HttpResponse,
) => Response | Promise<Response | void> | void;

✅ Built-in Middleware Support

You can register global or per-route middleware:

server.use(async (req, res) => {
	console.log(`[${req.method}] ${req.url}`);
});

server.get("/secure", async (req, res) => {
	if (!req.headers.get("authorization")) {
		return res.status(401).json({ error: "Unauthorized" });
	}
});

License

Distributed under the MIT License. See LICENSE for more information.