How do you access the url query params in nodejs?

Question

How do you access the url query params in nodejs with typescript? What I tried is here?

    /**
 * My Server app
 */
import * as Http from "http";
import * as url from "url";
import { HttpServer } from "./HttpServer";
import { TaxCalculator } from "./TaxCalculator";
export interface myReq extends Http.IncomingMessage {
  amount: string;
  rate: string;
}
/**
 * MyServer class
 * Create MyServer from HttpServer
 */
class MyServer extends HttpServer {
  /**
   * Create a new NodeServer object
   * @param port Port number of the server
   * @param name Name of the server
   */
  constructor(port: number, name: string) {
    super(port, name);
  }
  /**
   * Handle the Request in request nad populate the response to response
   * @param request Incoming Request
   * @param response Outgoing Response
   */
  onRequest(request: myReq, response: Http.ServerResponse): void {
    response.writeHead(200, {"Content-Type": "text/plain"});
// const { amount, rate } = url.parse(request.url, true).query;
    const query = url.parse(request.url, true).query;
    const tc = new TaxCalculator();
    const tax = tc.calculate(query.amount, query.rate);
    response.end(JSON.stringify(tax));
  }
}

// Create a server instance
const port = 8080;
new MyServer(port, "Test server");

The error is Argument of type 'string | string[]' is not assignable to parameter of type 'n umber'.

Answer 1

Inside your route handling middleware there are the req, res, next parameters of the router callback. You are looking for req.query.[your query param].

For typescript, you'll want to create an interface that extends express.Request and add your query param there. Then assign that type to your request param.

interface myReq extends express.Request {
    query: {
        [Whatever params you have in your route]: string;
    }
}

router.get("/", (req: myReq, res, next) => {
  ...
})

Youll also have to import express in the file if you havent already