Multipart File Upload in Ruby

Answer 1

There are several solutions here and here

Answer 2

Long problem, short answer: I was missing the binary mode for reading the image under Windows.

f = File.new(filename, File::RDWR)

had to be

f = File.new(filename, "rb")

Answer 3

Several options are discussed here:

http://stackoverflow.com/questions/184178/ruby-how-to-post-a-file-via-http-as-multipart-form-data