A general purpose uploader module for Net::SFTP. It can upload IO objects, files, and even entire directory trees via SFTP, and provides a flexible progress reporting mechanism.

To upload a single file to the remote server, simply specify both the local and remote paths:

  uploader = sftp.upload("/path/to/local.txt", "/path/to/remote.txt")

By default, this operates asynchronously, so if you want to block until the upload finishes, you can use the ‘bang’ variant:

  sftp.upload!("/path/to/local.txt", "/path/to/remote.txt")

Or, if you have multiple uploads that you want to run in parallel, you can employ the wait method of the returned object:

  uploads = %w(file1 file2 file3).map { |f| sftp.upload(f, "remote/#{f}") }
  uploads.each { |u| u.wait }

To upload an entire directory tree, recursively, simply pass the directory path as the first parameter:

  sftp.upload!("/path/to/directory", "/path/to/remote")

This will upload "/path/to/directory", it‘s contents, it‘s subdirectories, and their contents, recursively, to "/path/to/remote" on the remote server.

If you want to send data to a file on the remote server, but the data is in memory, you can pass an IO object and upload it‘s contents:

  require 'stringio'
  io = StringIO.new(data)
  sftp.upload!(io, "/path/to/remote")

The following options are supported:

• :progress - either a block or an object to act as a progress callback. See the discussion of "progress monitoring" below.
• :requests - the number of pending SFTP requests to allow at any given time. When uploading an entire directory tree recursively, this will default to 16, otherwise it will default to 2. Setting this higher might improve throughput. Reducing it will reduce throughput.
• :read_size - the maximum number of bytes to read at a time from the source. Increasing this value might improve throughput. It defaults to 32,000 bytes.
• :name - the filename to report to the progress monitor when an IO object is given as local. This defaults to "<memory>".

Progress Monitoring

Sometimes it is desirable to track the progress of an upload. There are two ways to do this: either using a callback block, or a special custom object.

Using a block it‘s pretty straightforward:

  sftp.upload!("local", "remote") do |event, uploader, *args|
    case event
    when :open then
      # args[0] : file metadata
      puts "starting upload: #{args[0].local} -> #{args[0].remote} (#{args[0].size} bytes}"
    when :put then
      # args[0] : file metadata
      # args[1] : byte offset in remote file
      # args[2] : data being written (as string)
      puts "writing #{args[2].length} bytes to #{args[0].remote} starting at #{args[1]}"
    when :close then
      # args[0] : file metadata
      puts "finished with #{args[0].remote}"
    when :mkdir then
      # args[0] : remote path name
      puts "creating directory #{args[0]}"
    when :finish then
      puts "all done!"
  end

However, for more complex implementations (e.g., GUI interfaces and such) a block can become cumbersome. In those cases, you can create custom handler objects that respond to certain methods, and then pass your handler to the uploader:

  class CustomHandler
    def on_open(uploader, file)
      puts "starting upload: #{file.local} -> #{file.remote} (#{file.size} bytes)"
    end

    def on_put(uploader, file, offset, data)
      puts "writing #{data.length} bytes to #{file.remote} starting at #{offset}"
    end

    def on_close(uploader, file)
      puts "finished with #{file.remote}"
    end

    def on_mkdir(uploader, path)
      puts "creating directory #{path}"
    end

    def on_finish(uploader)
      puts "all done!"
    end
  end

  sftp.upload!("local", "remote", :progress => CustomHandler.new)

If you omit any of those methods, the progress updates for those missing events will be ignored. You can create a catchall method named "call" for those, instead.