862b40b1fb
* added code * removed cdk code * added code examples * added ts files * added code * updated code * error handling code * Update nodejs/errorhandling/js/index.js Co-authored-by: Pratik Das <pratikd2001@gmail.com> Co-authored-by: Tom Hombergs <tom.hombergs@gmail.com>
126 lines
3.2 KiB
TypeScript
126 lines
3.2 KiB
TypeScript
import express, { Request, Response, NextFunction } from 'express'
|
|
import axios from 'axios'
|
|
|
|
const app = express()
|
|
const port:number = 3000
|
|
|
|
|
|
interface Product {
|
|
|
|
name: string
|
|
price: number
|
|
brand: string
|
|
category?: string
|
|
}
|
|
|
|
interface ProductCreationResponse {
|
|
productID: string
|
|
result: string
|
|
}
|
|
|
|
|
|
class AppError extends Error{
|
|
statusCode: number;
|
|
|
|
constructor(statusCode: number, message: string) {
|
|
super(message);
|
|
|
|
Object.setPrototypeOf(this, new.target.prototype);
|
|
this.name = Error.name;
|
|
this.statusCode = statusCode;
|
|
Error.captureStackTrace(this);
|
|
}
|
|
}
|
|
|
|
const requestLogger = (request: Request, response: Response, next: NextFunction) => {
|
|
console.log(`${request.method} url:: ${request.url}`);
|
|
next()
|
|
}
|
|
|
|
app.use(express.static('images'))
|
|
app.use(express.static('htmls'))
|
|
app.use(requestLogger)
|
|
|
|
app.use('/products', express.json({ limit: 100 }))
|
|
|
|
// Error handling Middleware functions
|
|
const errorLogger = (error: Error, request: Request, response: Response, next: NextFunction) => {
|
|
console.log( `error ${error.message}`)
|
|
next(error) // calling next middleware
|
|
}
|
|
|
|
const errorResponder = (error: AppError, request: Request, response: Response, next: NextFunction) => {
|
|
response.header("Content-Type", 'application/json')
|
|
|
|
const status = error.statusCode || 400
|
|
response.status(status).send(error.message)
|
|
}
|
|
|
|
const invalidPathHandler = (request: Request, response: Response, next: NextFunction) => {
|
|
response.status(400)
|
|
response.send('invalid path')
|
|
}
|
|
|
|
|
|
// handle post request for path /products
|
|
app.post('/products', (request: Request, response: Response) => {
|
|
const products = []
|
|
|
|
const name = request.body.name
|
|
|
|
const brand = request.body.brand
|
|
|
|
const category = request.body.category
|
|
|
|
if(name == null){
|
|
response.status(500).json({ message: "Mandatory field name is missing. " })
|
|
}else{
|
|
console.log(name + " " + brand)
|
|
|
|
products.push({name: request.body.name, brand: request.body.brand, price: request.body.price})
|
|
|
|
const productCreationResponse = {productID: "12345", result: "success"}
|
|
response.json(productCreationResponse)
|
|
}
|
|
})
|
|
|
|
app.get('/products', async (request: Request, response: Response, next: NextFunction)=>{
|
|
try{
|
|
const apiResponse = await axios.get("http://localhost:3001/products")
|
|
|
|
const jsonResponse = apiResponse.data
|
|
console.log("response "+jsonResponse)
|
|
|
|
response.send(jsonResponse)
|
|
}catch(error){
|
|
next(error)
|
|
}
|
|
|
|
})
|
|
|
|
app.get('/product', (request: Request, response: Response, next: NextFunction)=>{
|
|
|
|
axios.get("http://localhost:3001/product")
|
|
.then(jsonresponse=>response.send(jsonresponse))
|
|
.catch(next)
|
|
})
|
|
|
|
app.get('/productswitherror', (request, response) => {
|
|
let error:AppError = new AppError(400, `processing error in request at ${request.url}`)
|
|
error.statusCode = 400
|
|
throw error
|
|
})
|
|
|
|
app.get('/productswitherror', (request: Request, response: Response) => {
|
|
let error: AppError = new AppError(400, `processing error in request at ${request.url}`)
|
|
|
|
throw error
|
|
})
|
|
|
|
app.use(errorLogger)
|
|
app.use(errorResponder)
|
|
app.use(invalidPathHandler)
|
|
|
|
app.listen(port, () => {
|
|
console.log(`Server listening at port ${port}.`)
|
|
}) |