SSE 推送

r := znet.New()

r.GET("/sse", func(c *znet.Context) {
    if !c.IsSSE() {
      return
    }

    sse := znet.NewSSE(c, func(lastID string, opts *znet.SSEOption) {
      opts.RetryTime = 1000
      opts.HeartbeatsTime = 60000
    })

    go func() {
			for i := 0; i < 2; i++ {
				_ = sse.Send(ztype.ToString(i), "内容:" + ztype.ToString(i))
			}
			time.Sleep(time.Second / 2)
			sse.Stop()
    }()
		sse.Push()
	})