function asyncInsertMagFromFile(file, resolve) {
            //some asynchronous processing with file
            resolve();
          }

let magRequests = fs.readdirSync(storeDir).map(function(file) {
            return new Promise(resolve => {
              asyncInsertMagFromFile(file, resolve);
            });
          });

(async function loop() {
            fs.readdirSync(storeDir).forEach(function(file) {
              await new Promise(resolve =>
                asyncInsertMagFromFile(file, resolve)
              );
            });

          })();