Gzip compress using native browser libraries

gzip.ts

export async function gzip(input: Uint8Array|string): Promise<Uint8Array> {
  if (typeof input === 'string') {
    const encoder = new TextEncoder();
    input = encoder.encode(input);
  }
  const cs = new CompressionStream('gzip');
  const buffer = new Response(cs.readable).arrayBuffer();
  const writer = cs.writable.getWriter();
  await writer.write(input);
  await writer.close();
  return new Uint8Array(await buffer);
}