CSP - distribute expensive tasks to workers - A contrived example to show the strength and flexibility of CSP when compared to FRP.

csp-distribute.js

import {go, chan, put, take, buffers, putAsync, CLOSED} from 'js-csp'

const BUFFER_LIMIT = 100
const NUM_OF_WORKERS = 4

var inputChannel = csp.chan(buffers.dropping(BUFFER_LIMIT))

function fakeDataGenerator(){
  putAsync(Math.random())
  setTimeout(fakeDataGenerator, Math.random() * 2000)
}
fakeDataGenerator()

for(var i = 0; i < NUM_OF_WORKERS; i++){
  
  // imagine task.js takes a number and posts a response after an expensive computation.
  let worker = new Worker('task.js');
  let workerResponse = chan()
  worker.addEventListener('message', function(e) {
    putAsync(workerResponse, e.data)
  }, false);

  go(function*(){
    while(true){
      var value = yield take(inputChannel)
      if(value === CLOSED){
        workerResponse.close()
        worker.terminate()
        return;
      }
      worker.postMessage(value)
      var response = yield take(workerResponse)
      console.log(response)
    }
  })
}