examples/typescript/http-server-pool/express-worker_threads/src/main.ts

   1 import { exit } from 'node:process'
   2
   3 import express, { type Express, type Request, type Response } from 'express'
   4
   5 import { requestHandlerPool } from './pool.js'
   6
   7 /**
   8  * The goal of this example is to show how to use the poolifier library to create a pool of workers that can handle HTTP requests.
   9  * The request handler pool can also be used as a middleware in the express stack: application or router level.
  10  *
  11  * The express server is still single-threaded, but the request handler pool is multi-threaded.
  12  */
  13
  14 const port = 8080
  15 const expressApp: Express = express()
  16
  17 const emptyFunction = (): void => {
  18   /* Intentional */
  19 }
  20
  21 // Parse only JSON requests body
  22 expressApp.use(express.json())
  23
  24 expressApp.all('/api/echo', (req: Request, res: Response) => {
  25   requestHandlerPool
  26     .execute({ body: req.body }, 'echo')
  27     .then(response => {
  28       return res.send(response.body).end()
  29     })
  30     .catch(emptyFunction)
  31 })
  32
  33 expressApp.get('/api/factorial/:number', (req: Request, res: Response) => {
  34   const { number } = req.params
  35   requestHandlerPool
  36     .execute({ body: { number: parseInt(number) } }, 'factorial')
  37     .then(response => {
  38       return res.send(response.body).end()
  39     })
  40     .catch(emptyFunction)
  41 })
  42
  43 try {
  44   expressApp.listen(port, () => {
  45     console.info(
  46       `⚡️[express server]: Express server is started at http://localhost:${port}/`
  47     )
  48   })
  49 } catch (err) {
  50   console.error(err)
  51   exit(1)
  52 }