I am trying to use server action to save file, but i dont understand, how i get file Buffer from formdata.

client call-> 

  const handleUpload = async () => {
    setLoading(true);
    const formData = new FormData();
    formData.append('file', file);
    const uploadResponse = await uploadFile(formData); // server action
    setLoading(false);
    inputFile.current.value = null;
    setFile(undefined);
  }; 

server action -> 

export const uploadFile = async (formData: FormData) => {
  const file = formData.get('file');
  console.log('uploadFile');
  console.log(file);
  /**
    File {
      size: 612726,
      type: 'application/pdf',
      name: '2952940407.pdf',
      lastModified: 1716839583344
    }
   */
  fs.writeFile('./tmp/'+file.name, file.data, (err: any): any => {
    if (err) throw err;
    console.log('Results Received');
  });
  return;
};

Server action isnt working like that?