Since Heroku does not allow saving dynamic files to disk, I've run into a dilemma that I am hoping you can help me overcome. I have a text file that I can create in RAM. The problem is that I cannot find a gem or function that would allow me to stream the file to another FTP server. The Net/FTP gem I am using requires that I save the file to disk first. Any suggestions?
ftp = Net::FTP.new(domain)
ftp.passive = true
ftp.login(username, password)
ftp.chdir(path_on_server)
ftp.puttextfile(path_to_web_file)
ftp.close
The ftp.puttextfile function is what is requiring a physical file to exist.
StringIO.new provides an object that acts like an opened file. It's easy to create a method like puttextfile, by using StringIO object instead of file.
require 'net/ftp'
require 'stringio'
class Net::FTP
def puttextcontent(content, remotefile, &block)
f = StringIO.new(content)
begin
storlines("STOR " + remotefile, f, &block)
ensure
f.close
end
end
end
file_content = <<filecontent
<html>
<head><title>Hello!</title></head>
<body>Hello.</body>
</html>
filecontent
ftp = Net::FTP.new(domain)
ftp.passive = true
ftp.login(username, password)
ftp.chdir(path_on_server)
ftp.puttextcontent(file_content, path_to_web_file)
ftp.close
David at Heroku gave a prompt response to a support ticket I entered there.
You can use APP_ROOT/tmp for temporary file output. The existence of files created in this dir is not guaranteed outside the life of a single request, but it should work for your purposes.
Hope this helps,
David