'use strict'; const express = require('express'); const app = express(); app.get('/api/p1', p1); app.get('/api/p2', p2); app.get('/api/p3', p3); app.use(errorHandler); app.listen(3000); function p1(request, response) { try { throw new Error('p1'); } catch (error) { response.status(500).send(error.toString()); } } function p2(request, response) { try { throw new Error('p2'); } catch (error) { response.status(500).send(error.toString()); } } function p3(request, response) { throw new Error('p3'); } function errorHandler(error, request, response, next) { // there must be 4 arguments response.status(500).send(error.toString()); }