Function invokeVisualizer

internal/driver/commands.go:410–448

(suffix string, visualizers []string)

}

func invokeVisualizer(suffix string, visualizers []string) PostProcessor {
	return func(input io.Reader, output io.Writer, ui plugin.UI) error {
		tempFile, err := newTempFile(os.TempDir(), "pprof", "."+suffix)
		if err != nil {
			return err
		}
		deferDeleteTempFile(tempFile.Name())
		if _, err := io.Copy(tempFile, input); err != nil {
			return err
		}
		tempFile.Close()
		// Try visualizers until one is successful
		for _, v := range visualizers {
			// Separate command and arguments for exec.Command.
			args := strings.Split(v, " ")
			if len(args) == 0 {
				continue
			}
			viewer := exec.Command(args[0], append(args[1:], tempFile.Name())...)
			viewer.Stderr = os.Stderr
			if err = viewer.Start(); err == nil {
				// Wait for a second so that the visualizer has a chance to
				// open the input file. This needs to be done even if we're
				// waiting for the visualizer as it can be just a wrapper that
				// spawns a browser tab and returns right away.
				defer func(t <-chan time.Time) {
					<-t
				}(time.After(time.Second))
				// On interactive mode, let the visualizer run in the background
				// so other commands can be issued.
				if !interactiveMode {
					return viewer.Wait()
				}
				return nil
			}
		}
		return err
	}
}

// stringToBool is a custom parser for bools. We avoid using strconv.ParseBool
// to remain compatible with old pprof behavior (e.g., treating "" as true).