nodejs - await async in loop

node.js

res.write('start');
    var files = searchRecursive(config.app.publicPath, '.scss');
    //foreach is not promise-aware. so use map
    //map return promises
    var promises = await files.map(async(scss)=>{
      var css = scss.replace('.scss','.min.css');
      var map = scss.replace('.scss','.min.css.map');
      
      var result = await sassAsyncRender(scss,css,map);
      res.write(JSON.stringify({result}));
    });
    await Promise.all(promises); //wait for all promise to complete
 
    res.write('end');
    res.end();