elem.firstChild.setAttribute is not a function

[anandguna]

Hi,

As per our requirement we need to send PDF file as stream. Is it possible use ws.js.

when i am using the below line of code i am getting an error "elem.firstChild.setAttribute is not a function"
I am passing file relative path in tempPath.
ws.addAttachment(ctx, "request", "//*[local-name(.)='Envelope']", tempPath, "application/pdf")

Regards,
Anand