7. Async¶

submitRaw() / submit<T>() / download(sink) all return a Promise. In Node, async/await plays the role of a coroutine.

Non-Blocking Guarantee¶

undici uses asynchronous sockets based on the libuv event loop. So while waiting for a response, the event loop thread is not blocked. The runtime's asynchronous I/O provides this, so no separate worker scheduler is needed.

async function notifyMatchResult(client: ZLinkHttpClient, result: MatchResult): Promise<void> {
  const response = await client.post(`/matches/${result.matchId}/result`)
    .body(result)
    .submit<AckRes>();

  if (!response.body.accepted) {
    throw new ZLinkFrameworkException(ZLinkFrameworkErrorKind.RequestFailed, 'match result was not accepted');
  }
}

Only DNS resolution (getaddrinfo) is blocking at the OS level, but Node offloads it to a background thread pool, so the event loop isn't blocked.

Continuation Resume Location¶

Node has a single event loop, so there's no concept of injecting a continuation resume location. The .coroutines() builder item doesn't exist — only standard Promise/await are provided.

No Blocking Path¶

Node has no synchronous blocking HTTP access. It provides no blocking submit path — every submit is awaited.

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