How to post a file via HTTP as multipart/form-data to Facebook?

I would like to post a new photo to a user using Net::HTTP::multipart
from a Heroku application to Facebook.

I have the following JSON object:

{"message"=>"My message",

“image”=>#<ActionDispatch::Http::UploadedFile:0x00000004242490
@original_filename=“neEZYMAnBI.jpg”,
@content_type=“application/octet-stream”, @headers=“Content-Disposition:
form-data; name=“image”;
filename=”/home/user/public/direct/fb_images/neEZYMAnBI.jpg"\r\nContent-Type:
application/octet-stream\r\n",
@tempfile=#<File:/app/tmp/RackMultipart20110818-1-18qnwtj>>,
“method”=>“post”, “access_token”=>“my_access_token”, “format”=>“json”}

I tried to use:

require 'net/http/post/multipart'

url =

URI.parse(‘https://graph.facebook.com/me/photos?access_token=#{params[:access_token]}’)
File.open(params[@tempfile]) do |jpg|
req = Net::HTTP::Post::Multipart.new url.path,
“file” => UploadIO.new(jpg, “image/jpeg”, “image.jpg”)
res = Net::HTTP.start(url.host, url.port) do |http|
http.request(req)
end
end

But:

  1. It is not sending the data.
  2. I cannot find how to send the params[:message] with the file in
    order to have a caption for the image.

Can someone suggest a solution?

Thanks

I think that this can help :

class FbPhotoUploader
require ‘net/http/post/multipart’ # multipart-post gem
require ‘mime/types’ #mime-types gem
require ‘net/https’

def upload(path, access_token, options={})
photo = File.open(path)
params = {:access_token => access_token}
params.merge!(options)
url = URI.parse(“https://graph.facebook.com/me/photos”)

req = Net::HTTP::Post::Multipart.new 

“#{url.path}?#{params.to_query}”,
“file” => UploadIO.new(photo, mime_for_file(photo), photo.path)

n = Net::HTTP.new(url.host, url.port)
n.use_ssl = true
n.verify_mode = OpenSSL::SSL::VERIFY_NONE
n.start do |http|
  http.request(req)
end

end

private
def mime_for_file(f)
m = MIME::Types.type_for(f.path.split(’’).last)
m.empty? ? “application/octet-stream” : m.to_s
end
end