capnwasm chat

capnwasm

// Browser
const r = cap.callBuilder(IFC, M_POST, PostParamsBuilder);
r.params.author = author;
r.params.text   = text;
await r.send().promise;

// WebSocket subscribe
for await (const chunk of sub.updates) {
  const m = openChatMessage(cpp, chunk);
  render({ id: Number(m.id), author: m.author, text: m.text });
}

// REST poll
await r.send({
  resultsReader: ChatMessageListReader,
  extract: (rdr) => { for (let i = 0; i < rdr.items.length; i++) ... },
}).promise;

Schema-driven binary frames, fields read from wasm linear memory by precomputed offset, no JSON in the chat path.

capnweb

// Browser
const main = newWebSocketRpcSession("/capnweb-chat-ws");
//        OR newHttpBatchRpcSession("/capnweb-chat-http");
await main.post(author, text);

// WebSocket subscribe (callback stub)
class Sub extends RpcTarget {
  onMessage(m) { render(m); }
}
await main.subscribe(new Sub());

// REST poll
const items = await main.getMessagesSince(cursor);

JSON-shaped messages, server holds callback.dup() and invokes onMessage per broadcast — the cap-passing pattern.