Streaming bz2 decompression in browser (newline delimited JSON)

streaming-decompress-bz2.html

<script src="https://unpkg.com/unbzip2-stream@1.2.5/dist/unbzip2-stream.min.js"></script>
<script>
async function loadBzipJson(url, cb) {
  let text = "";
  let bz2 = window.unbzip2Stream();
  bz2.on('data', (d) => {
    text += new TextDecoder('utf-8').decode(d);
    while(text.includes("\n")) {
      cb(JSON.parse(text.slice(0, text.indexOf("\n"))));
      text = text.slice(text.indexOf("\n")+1);
    }
  });
  let reader = await fetch(url).then(r => r.body.getReader())
  let r;
  while(r = await reader.read(), !r.done) {
    bz2.write( r.value );
  }
}

let i = 0;
loadBzipJson("https://files.pushshift.io/reddit/comments/RC_2017-11.bz2", (obj) => {
  console.log(obj);
});
</script>