Fair simple decorator based router, with GET/POST and middleware support.

live demo: https://yieldray-decorator_router_demo.web.val.run/

Create val
import { get, post, all, use, registered, handler, type Context } from "https://esm.town/v/yieldray/decorator_router";
import { parseBearerAuth, transformResponse } from "https://esm.sh/serve-router@1.1.0/utils";

interface User {
    id: number;
    name: string;
}

const users: User[] = [
    { id: 0, name: "Alice" },
    { id: 1, name: "Ray" },
];

class _Server {
    /**
     * Decorator @get: Parses URLSearchParams into an object as the first parameter.
     */

    @get("/users")
    getAllUsers() {
        return users; // Automatically wrapped in a Response.json
    }

    @get("/getUserByName") // GET /getUserByName?name=Alice
    getUserByName({ name }: Record<string, string>) {
        const user = users.find((u) => u.name === name);
        if (user) {
            return user; // Automatically wrapped as Response.json(user)
        }

        // Optionally, manually return a Response object
        return Response.json({ error: "not found" }, { status: 404 });
    }

    @get("/user/:id") // GET /user/123
    user(_: unknown, { params: { id } }: Context) {
        return users.find((u) => u.id === Number(id));
    }

    /**
     * Decorator @post: Parses the request body into an object as the first parameter.
     */

    @post("/user") // POST /user
    async createUser(user: User) {
        if (users.find((u) => u.id === user.id)) {
            return { error: "already exists!" };
        }
        await users.push(user); // Assume insertion into a database
        return { ok: true, users };
    }

    @post("/user/:id") // POST /user/123
    async updateUser(user: User, { params: { id }, request }: Context) {
        const token = parseBearerAuth(request.headers.get("Authorization")!);
        // Additional logic here...
    }

    @all("/")
    home({ request }: { request: Request }) {
        return {
            registered,
            method: request.method,
            url: request.url,
            headers: Object.fromEntries(request.headers.entries()),
        };
    }

    @use("/*")
    async corsMiddleware({ next, request }: Context) {
        const resp = await next();
        return transformResponse(resp, {
            headers: {
                "Access-Control-Allow-Origin": request.headers.get("origin") || "*",
            },
        });
    }
}

// For Deno:
Deno.serve(handler);
// For val.town:
export default handler;