How to get FileDescriptor and id from filename

Hi Team,

I'm using nodejs for the chatbot, when i upload a file, i can get filename printed with the "content"

nodeSDK.im.sendMessageToJid(content, from.jid);

Can you please help me, how can i get a FileDescriptor and id for that file?

Also what is the URL of the location that file is uploaded?

Thanks,

Rajesh.