From: Andrew Stewart <boss@...>
Date: 2006-11-09T02:28:03+09:00
Subject: Net::SSH Data Stream Problem

Hello,

I am trying to copy a file from my local machine to a remote machine  
using Net::SSH.  The copy fails part way leaving the file partly  
written on the remote machine.  The size of the remote file portion  
is always 131072 bytes (128 kB).  My local file is ~1.2MB.  This  
leads me to suspect that the data are being fed in chunks and  
something is going wrong after the first chunk -- though that's a guess.

Here's the output:

Copying /path/to/my/file.zip to /path/to/remote/directory/ 
file.zip...done.
/usr/local/lib/ruby/gems/1.8/gems/net-ssh-1.0.9/lib/net/ssh/transport/ 
session.rb:256:in `wait_for_message': disconnected: Received data for  
nonexistent channel 0. (2) (Net::SSH::Transport::Disconnect)
         from /usr/local/lib/ruby/gems/1.8/gems/net-ssh-1.0.9/lib/net/ 
ssh/transport/session.rb:240:in `wait_for_message'
         from /usr/local/lib/ruby/gems/1.8/gems/net-ssh-1.0.9/lib/net/ 
ssh/connection/driver.rb:148:in `process'
         from /usr/local/lib/ruby/gems/1.8/gems/net-ssh-1.0.9/lib/net/ 
ssh/connection/driver.rb:138:in `loop'
         from /usr/local/lib/ruby/gems/1.8/gems/net-ssh-1.0.9/lib/net/ 
ssh/service/process/popen3.rb:66:in `popen3'
[snipped rest of trace]

Interestingly the 'puts "...done."' line is executed before the error  
is thrown.  Since session.process.popen3 is synchronous, does that  
not imply that the copy has finished?

And here's the code (based on Ruby Cookbook recipe 14.11):

require 'rubygems'
require 'net/ssh'

host = 'xyz.com'
user = 'me'
upload_dir = '/path/to/remote/directory/'
my_file = '/path/to/my/file.zip'

def copy_file(session, source_path, destination_path=nil)
   destination_path ||= source_path
   cmd = %{cat > "#{destination_path.gsub('"', '\"')}"}
   session.process.popen3 cmd do |stdin, stdout, stderr|
     print "Copying #{source_path} to #{destination_path}..."
     open(source_path) { |f| stdin.write f.read }
     puts "done."
   end
end

Net::SSH.start(host, :username => user) do |session|
   copy_file session, my_file, my_file.sub(/^.*\//, "#{upload_dir}")
end

I would greatly appreciate any help.

Thanks and regards,
Andy Stewart