Create a CURL multipart/form-data request

My company needs a PHP function that creates this HTTP request: --a7V4kRcFA8E79pivMuV2tukQ85cmNKeoEgJgq Content-Type:application/json; charset=UTF-8 Content-Disposition: form-data; name="json" { "desc":"A new file", "title":"a_new_file" } --a7V4kRcFA8E79pivMuV2tukQ85cmNKeoEgJgq Content-Disposition: form-data; name="fileData"; filename="foo" Content-Type: application/octet-stream; charset=ISO-8859-1 --a7V4kRcFA8E79pivMuV2tukQ85cmNKeoEgJgq--