phpengine/watcher.js

const fs = require('fs');
const {exec} = require('child_process');

// this is for fix because the event fire twice
let twiceFix = false;

function compileAll(event, fname) {
  console.log(`${fname} as changed`);
  if (event == 'change' && twiceFix) {
    twiceFix = false;
    exec('npx sass ui/css/omlink.scss:ui/css/omlink.css', (error, out, err) => {
      console.log('------------------------------ CSS built ------------------------------');
      if (error) {
        console.log(error);
        return;
      }
      exec('npm run build', (error, out, err) => {
        console.log('------------------------------ Bundle JS/CSS ------------------------------');
        if (error) {
          console.log(error);
          return;
        }
      });
    });
  }
  twiceFix = true;
}

console.log('Adding watcher for ui/css/omlink.scss');
fs.watch('ui/css/omlink.scss', function (event, fname) {
  compileAll(event, fname);
});

console.log('Adding watcher for ui/js/onlink.js');
fs.watch('ui/js/omlink.js', function (event, fname) {
  compileAll(event, fname);
});