Not found path not work with express router

[sergebesson]

Describe the bug
if using an express router instead of app express, a path not defined does not return the Not Found error

Examples and context
example with code bug_openapi.js

const express = require("express");
const { OpenApiValidator } = require("express-openapi-validator");

async function execute() {

	const router = express.Router();
	await new OpenApiValidator({
		apiSpec: {
			openapi: "3.0.0",
			info: { version: "1.0.0", title: "test bug OpenApiValidator" },
			servers: [{ url: "http://localhost:8080/api/" }],
			paths: {
				"/": {get: {responses: {200: {description: "home api"}}}}
			},
		},
	}).install(router);

	router.get("/", (req, res) => res.status(200).send("home api\n"));
	router.get("/notDefined", (req, res) => res.status(200).send("url api not defined\n"));

	const app = express();
	app.get('/', (req, res) => res.status(200).send("home\n"));
	app.use("/api", router);

	app.listen(3000);
	console.log("server start port 3000");

}

execute().catch((error) => console.error(error.stack));

node bug_openapi.js to start server
curl http://localhost:3000/api/notDefined return 200 - url api not defined.
however, a path is not defined in apiSpec. The return should have been 404 Not Found

[cdimascio]

@sergebesson thanks for the issue. will get this fixed

[cdimascio]

@sergebesson this is fixed in v3.16.1

[cdimascio]

thank you for the reproducible code snippet. i used it as the test here

[sergebesson]

thank you for fix :-)