StreamingBeta

Functions can stream a response so the first bytes reach the user before the work is finished. Streaming is on by default for every runtime.

export default {
  fetch() {
    const enc = new TextEncoder();
    return new Response(new ReadableStream({
      async start(c) {
        for (const w of ['one', 'two', 'three']) {
          c.enqueue(enc.encode(w + '\n'));
          await new Promise((r) => setTimeout(r, 300));
        }
        c.close();
      },
    }));
  },
};

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