Function receiveText

web/app.js:205–235

(conn, li, progress)

// receiveText reads the whole incoming stream into memory and shows
// it as copyable text under the connection's list item.
async function receiveText(conn, li, progress) {
  try {
    const chunks = [];
    let n = 0;
    for (let chunk; (chunk = await conn.read()) !== null; ) {
      chunks.push(chunk);
      n += chunk.length;
      progress.textContent = `${n} bytes`;
    }
    conn.close();
    const all = new Uint8Array(n);
    let off = 0;
    for (const c of chunks) {
      all.set(c, off);
      off += c.length;
    }
    const text = new TextDecoder().decode(all);
    const box = document.createElement("code");
    box.className = "recv-text";
    box.textContent = text;
    const copyBtn = document.createElement("button");
    copyBtn.textContent = "Copy";
    copyBtn.onclick = () => navigator.clipboard.writeText(text);
    li.append(box, copyBtn);
    progress.textContent = `done, ${n} bytes`;
  } catch (err) {
    conn.close();
    progress.textContent = "failed: " + err.message;
    window.tcTest.errors.push(String(err));
  }
}

// hashSink is the test-mode receiver: instead of the file picker
// (which needs a user gesture that headless Chrome can't provide), it