Chapter 10

1. An error handler is used to catch errors in an application, and logging is a strategy used to grab pieces of information throughout runtimes, such as errors or relevant information.
2. You can define them all at the end of the app.use definition, as follows:

import * as bodyParser from 'body-parser'
import * as express from 'express'
import * as mongoose from 'mongoose'
import { APIRoute } from '../src/routes/api'
import { OrderRoute } from '../src/routes/order'
import { UserRoute } from '../src/routes/user'
import * as errorHandler from '../src/utility/errorHandler'

class App {
  public app: express.Application
  public userRoutes: UserRoute = new UserRoute()
  public apiRoutes: APIRoute = new APIRoute()
  public orderRoutes: OrderRoute = new OrderRoute()
  public mongoUrl: string = 'mongodb://localhost...