export async function fileAsBase64(f: File) {
  const reader = new FileReader();
  reader.readAsArrayBuffer(f);
  return new Promise<string>((resolve, reject) => {
    reader.onload = () => {
      const result = reader.result as ArrayBuffer;
      const buffer = Buffer.from(result);
      resolve(buffer.toString("base64"));
    };
    reader.onerror = () => reject(reader.error);
  });
}