Kibana plugin install process ignored a js file

[bbking]

Hi all! I have the following file structure for a custome Kibana plugin. The constants.js contains some constants that are shared between front and back end. Once I create a distributable archive file and install the plugin using bin/kibana-plugin install file://[path], it shows FATAL Error: Cannot find module '../../../constants'.
I checked that in plugins folder, the contants.js file is not there.
Does anyone have any ideas about it? Why does the file not show up when I install the plugin?

public/
server/
index.js
constants.js
package.json

[nickpeihl]

Your constants module may not be exporting anything or the relative path may be incorrect.