}

			end, err = strconv.ParseInt(endStr, 10, 64)
			if err != nil {
				log.Printf("failed to parse end parameter %q: %v", endStr, err)
				return
			}
		}

		c := traceviewer.ViewerDataTraceConsumer(w, start, end)
		if err := generateTrace(parsed, opts, c); err != nil {
			log.Printf("failed to generate trace: %v", err)
		}
	})
}

	ConsumeViewerFrame func(key string, f format.Frame)
	Flush              func()
}

// ViewerDataTraceConsumer returns a TraceConsumer that writes to w. The
// startIdx and endIdx are used for splitting large traces. They refer to
// indexes in the traceEvents output array, not the events in the trace input.
func ViewerDataTraceConsumer(w io.Writer, startIdx, endIdx int64) TraceConsumer {
	allFrames := make(map[string]format.Frame)