流式输出

1. Token生成 → 2. 批量组装 → 3. 流式传输 → 4. 客户端渲染

HTTP/1.1 200 OK
Content-Type: text/event-stream
Cache-Control: no-cache

data: {"id":"msg-001","type":"content_block_delta","delta":{"text":"Hello"}}
data: {"id":"msg-001","type":"content_block_delta","delta":{"text":" world"}}
data: {"id":"msg-001","type":"content_block_stop"}
data: [DONE]

const eventSource = new EventSource('/api/stream');
eventSource.onmessage = (event) => {
  if (event.data === '[DONE]') {
    eventSource.close();
    return;
  }
  const chunk = JSON.parse(event.data);
  displayContent(chunk.delta.text);
};

class StreamBuffer:
    def __init__(self, size=5):  # 2025标准：5-10 tokens
        self.buffer = []
        self.size = size
    
    def add(self, token):
        self.buffer.append(token)
        if len(self.buffer) >= self.size:
            return self.flush()
        return None
    
    def flush(self):
        content = self.buffer
        self.buffer = []
        return content

async def stream_with_retry(prompt, max_retries=3):
    for attempt in range(max_retries):
        try:
            async for chunk in generate_stream(prompt):
                yield chunk
            break
        except StreamError as e:
            if attempt == max_retries - 1:
                yield {"error": str(e)}
            await asyncio.sleep(2 ** attempt)