class Net::SFTP::Session

The Session class encapsulates a single SFTP channel on a Net::SSH connection. Instances of this class are what most applications will interact with most, as it provides access to both low-level (mkdir, rename, remove, symlink, etc.) and high-level (upload, download, etc.) SFTP operations.

Although Session makes it easy to do SFTP operations serially, you can also set up multiple operations to be done in parallel, too, without needing to resort to threading. You merely need to fire off the requests, and then run the event loop until all of the requests have completed:

handle1 = sftp.open!("/path/to/file1")
handle2 = sftp.open!("/path/to/file2")

r1 = sftp.read(handle1, 0, 1024)
r2 = sftp.read(handle2, 0, 1024)
sftp.loop { [r1, r2].any? { |r| r.pending? } }

puts "chunk #1: #{r1.response[:data]}"
puts "chunk #2: #{r2.response[:data]}"

By passing blocks to the operations, you can set up powerful state machines, to fire off subsequent operations. In fact, the Net::SFTP::Operations::Upload and Net::SFTP::Operations::Download classes set up such state machines, so that multiple uploads and/or downloads can be running simultaneously.

The convention with the names of the operations is as follows: if the method name ends with an exclamation mark, like read!, it will be synchronous (e.g., it will block until the server responds). Methods without an exclamation mark (e.g. read) are asynchronous, and return before the server has responded. You will need to make sure the SSH event loop is run in order to process these requests. (See loop.)

Constants

HIGHEST_PROTOCOL_VERSION_SUPPORTED

The highest protocol version supported by the Net::SFTP library.

Attributes

channel[R]

The Net::SSH::Connection::Channel object that the SFTP session is being processed by.

pending_requests[R]

The hash of pending requests. Any requests that have been sent and which the server has not yet responded to will be represented here.

protocol[R]

The protocol instance being used by this SFTP session. Useful for querying the protocol version in effect.

session[R]

A reference to the Net::SSH session object that powers this SFTP session.

state[R]

The state of the SFTP connection. It will be :opening, :subsystem, :init, :open, or :closed.

Public Class Methods

new(session, &block) click to toggle source

Creates a new Net::SFTP instance atop the given Net::SSH connection. This will return immediately, before the SFTP connection has been properly initialized. Once the connection is ready, the given block will be called. If you want to block until the connection has been initialized, try this:

sftp = Net::SFTP::Session.new(ssh)
sftp.loop { sftp.opening? }
# File lib/net/sftp/session.rb, line 78
def initialize(session, &block)
  @session    = session
  @input      = Net::SSH::Buffer.new
  self.logger = session.logger
  @state      = :closed

  connect(&block)
end

Public Instance Methods

block(handle, offset, length, mask) → request click to toggle source
block(handle, offset, length, mask) { |response| ... } → request

Creates a byte-range lock on the file specified by the given handle. This operation is only available in SFTP protocol versions 6 and higher. The lock may be either mandatory or advisory.

The handle parameter is a file handle, as obtained by the open method.

The offset and length parameters describe the location and size of the byte range.

The mask describes how the lock should be defined, and consists of some combination of the following bit masks:

  • 0x0040 - Read lock. The byte range may not be accessed for reading by via any other handle, though it may be written to.

  • 0x0080 - Write lock. The byte range may not be written to via any other handle, though it may be read from.

  • 0x0100 - Delete lock. No other handle may delete this file.

  • 0x0200 - Advisory lock. The server need not honor the lock instruction.

Once created, the lock may be removed via the unblock method.

# File lib/net/sftp/session.rb, line 691
def block(handle, offset, length, mask, &callback)
  request :block, handle, offset, length, mask, &callback
end
block!(handle, offset, length, mask, &callback) click to toggle source

Identical to block, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

# File lib/net/sftp/session.rb, line 698
def block!(handle, offset, length, mask, &callback)
  wait_for(block(handle, offset, length, mask, &callback))
end
close(handle) → request click to toggle source
close(handle) { |response| ... } → request

Closes an open handle, whether obtained via open, or opendir. Returns immediately with a Request object. If a block is given, it will be invoked when the server responds.

sftp.open("/path/to/file") do |response|
  raise "fail!" unless response.ok?
  sftp.close(response[:handle])
end
sftp.loop
# File lib/net/sftp/session.rb, line 207
def close(handle, &callback)
  request :close, handle, &callback
end
close!(handle, &callback) click to toggle source

Identical to close, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it returns the Response object for this request.

sftp.close!(handle)
# File lib/net/sftp/session.rb, line 216
def close!(handle, &callback)
  wait_for(close(handle, &callback))
end
close_channel() click to toggle source

Closes the SFTP connection, but not the SSH connection. Blocks until the session has terminated. Once the session has terminated, further operations on this object will result in errors. You can reopen the SFTP session via the connect method.

# File lib/net/sftp/session.rb, line 727
def close_channel
  return unless open?
  channel.close
  loop { !closed? }
end
closed?() click to toggle source

Returns true if the connection has been closed.

# File lib/net/sftp/session.rb, line 739
def closed?
  state == :closed
end
connect(&block) click to toggle source

Attempts to establish an SFTP connection over the SSH session given when this object was instantiated. If the object is already open, this will simply execute the given block (if any), passing the SFTP session itself as argument. If the session is currently being opened, this will add the given block to the list of callbacks, to be executed when the session is fully open.

This method does not block, and will return immediately. If you pass a block to it, that block will be invoked when the connection has been fully established. Thus, you can do something like this:

sftp.connect do
  puts "open!"
end

If you just want to block until the connection is ready, see the connect! method.

# File lib/net/sftp/session.rb, line 766
def connect(&block)
  case state
  when :open
    block.call(self) if block
  when :closed
    @state = :opening
    @channel = session.open_channel(&method(:when_channel_confirmed))
    @packet_length = nil
    @protocol = nil
    @on_ready = Array(block)
  else # opening
    @on_ready << block if block
  end

  self
end
connect!(&block) click to toggle source

Same as the connect method, but blocks until the SFTP connection has been fully initialized.

# File lib/net/sftp/session.rb, line 785
def connect!(&block)
  connect(&block)
  loop { opening? }
  self
end
dir() click to toggle source

Returns a Net::SFTP::Operations::Dir instance, which can be used to conveniently iterate over and search directories on the remote server.

sftp.dir.glob("/base/path", "*   /*.rb") do |entry|
  p entry.name
end

See Net::SFTP::Operations::Dir for a more detailed discussion of how to use this.

# File lib/net/sftp/session.rb, line 153
def dir
  @dir ||= Operations::Dir.new(self)
end
download(remote, local, options={}, &block) click to toggle source

Initiates a download from remote to local, asynchronously. This method will return a new Net::SFTP::Operations::Download instance, and requires that the event loop be run in order for the download to progress. See Net::SFTP::Operations::Download for a full discussion of hos this method can be used.

download = sftp.download("/remote/path", "/local/path")
download.wait
# File lib/net/sftp/session.rb, line 114
def download(remote, local, options={}, &block)
  Operations::Download.new(self, local, remote, options, &block)
end
download!(remote, local=nil, options={}, &block) click to toggle source

Identical to download, but blocks until the download is complete. If local is omitted, downloads the file to an in-memory buffer and returns the result as a string; otherwise, returns the Net::SFTP::Operations::Download instance.

# File lib/net/sftp/session.rb, line 122
def download!(remote, local=nil, options={}, &block)
  require 'stringio' unless defined?(StringIO)
  destination = local || StringIO.new
  result = download(remote, destination, options, &block).wait
  local ? result : destination.string
end
file() click to toggle source

Returns an Net::SFTP::Operations::FileFactory instance, which can be used to mimic synchronous, IO-like file operations on a remote file via SFTP.

sftp.file.open("/path/to/file") do |file|
  while line = file.gets
    puts line
  end
end

See Net::SFTP::Operations::FileFactory and Net::SFTP::Operations::File for more details.

# File lib/net/sftp/session.rb, line 140
def file
  @file ||= Operations::FileFactory.new(self)
end
fsetstat(handle, attrs, &callback) click to toggle source

The fsetstat method is identical to the setstat method, with the exception that it takes a handle as the first parameter, such as would be obtained via the open or opendir methods. (See the setstat method for full documentation.)

# File lib/net/sftp/session.rb, line 378
def fsetstat(handle, attrs, &callback)
  request :fsetstat, handle, attrs, &callback
end
fsetstat!(handle, attrs, &callback) click to toggle source

Identical to the fsetstat method, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

sftp.fsetstat!(handle, :permissions => 0644)
# File lib/net/sftp/session.rb, line 387
def fsetstat!(handle, attrs, &callback)
  wait_for(fsetstat(handle, attrs, &callback))
end
fstat(handle, flags=nil, &callback) click to toggle source

The fstat method is identical to the stat and lstat methods, with the exception that it takes a handle as the first parameter, such as would be obtained via the open or opendir methods. (See the lstat method for full documentation).

# File lib/net/sftp/session.rb, line 327
def fstat(handle, flags=nil, &callback)
  request :fstat, handle, flags, &callback
end
fstat!(handle, flags=nil, &callback) click to toggle source

Identical to the fstat method, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the attribute object describing the path.

puts sftp.fstat!(handle).permissions
# File lib/net/sftp/session.rb, line 336
def fstat!(handle, flags=nil, &callback)
  wait_for(fstat(handle, flags, &callback), :attrs)
end
loop(&block) click to toggle source

Runs the SSH event loop while the given block returns true. This lets you set up a state machine and then “fire it off”. If you do not specify a block, the event loop will run for as long as there are any pending SFTP requests. This makes it easy to do thing like this:

sftp.remove("/path/to/file")
sftp.loop
# File lib/net/sftp/session.rb, line 800
def loop(&block)
  block ||= Proc.new { pending_requests.any? }
  session.loop(&block)
end
Also aliased as: loop_forever
loop_forever(&block)
Alias for: loop
lstat(path, flags=nil) → request click to toggle source
lstat(path, flags=nil) { |response| ... } → request

This method is identical to the stat method, with the exception that it will not follow symbolic links (thus allowing you to stat the link itself, rather than what it refers to). The flags parameter is not used in SFTP protocol versions prior to 4, and will be ignored in those versions of the protocol that do not use it. For those that do, however, you may provide hints as to which file proprties you wish to query (e.g., if all you want is permissions, you could pass the Net::SFTP::Protocol::V04::Attributes::F_PERMISSIONS flag as the value for the flags parameter).

The method returns immediately with a Request object. If a block is given, it will be invoked when the server responds. The :attrs property of the response will contain an Attributes instance appropriate for the the protocol version (see Protocol::V01::Attributes, Protocol::V04::Attributes, and Protocol::V06::Attributes).

request = sftp.lstat("/path/to/file") do |response|
  raise "fail!" unless response.ok?
  puts "permissions: %04o" % response[:attrs].permissions
end
request.wait
# File lib/net/sftp/session.rb, line 310
def lstat(path, flags=nil, &callback)
  request :lstat, path, flags, &callback
end
lstat!(path, flags=nil, &callback) click to toggle source

Identical to the lstat method, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the attribute object describing the path.

puts sftp.lstat!("/path/to/file").permissions
# File lib/net/sftp/session.rb, line 319
def lstat!(path, flags=nil, &callback)
  wait_for(lstat(path, flags, &callback), :attrs)
end
mkdir(path, attrs={}) → request click to toggle source
mkdir(path, attrs={}) { |response| ... } → request

Creates the named directory on the remote server. If an attribute hash is given, it must map to the set of attributes supported by the version of the SFTP protocol in use. (See Protocol::V01::Attributes, Protocol::V04::Attributes, and Protocol::V06::Attributes.)

sftp.mkdir("/path/to/directory", :permissions => 0550).wait
# File lib/net/sftp/session.rb, line 488
def mkdir(path, attrs={}, &callback)
  request :mkdir, path, attrs, &callback
end
mkdir!(path, attrs={}, &callback) click to toggle source

Identical to mkdir, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

sftp.mkdir!("/path/to/directory", :permissions => 0550)
# File lib/net/sftp/session.rb, line 497
def mkdir!(path, attrs={}, &callback)
  wait_for(mkdir(path, attrs, &callback))
end
open(path, flags="r", options={}) → request click to toggle source
open(path, flags="r", options={}) { |response| ... } → request

Opens a file on the remote server. The flags parameter determines how the flag is open, and accepts the same format as IO#open (e.g., either a string like “r” or “w”, or a combination of the IO constants). The options parameter is a hash of attributes to be associated with the file, and varies greatly depending on the SFTP protocol version in use, but some (like :permissions) are always available.

Returns immediately with a Request object. If a block is given, it will be invoked when the server responds, with a Response object as the only parameter. The :handle property of the response is the handle of the opened file, and may be passed to other methods (like close, read, write, and so forth).

sftp.open("/path/to/file") do |response|
  raise "fail!" unless response.ok?
  sftp.close(response[:handle])
end
sftp.loop
# File lib/net/sftp/session.rb, line 181
def open(path, flags="r", options={}, &callback)
  request :open, path, flags, options, &callback
end
open!(path, flags="r", options={}, &callback) click to toggle source

Identical to open, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the handle of the newly opened file.

handle = sftp.open!("/path/to/file")
# File lib/net/sftp/session.rb, line 190
def open!(path, flags="r", options={}, &callback)
  wait_for(open(path, flags, options, &callback), :handle)
end
open?() click to toggle source

Returns true if the connection has been initialized.

# File lib/net/sftp/session.rb, line 734
def open?
  state == :open
end
opendir(path) → request click to toggle source
opendir(path) { |response| ... } → request

Attempts to open a directory on the remote host for reading. Once the handle is obtained, directory entries may be retrieved using the readdir method. The method returns immediately with a Request object. If a block is given, it will be invoked when the server responds.

sftp.opendir("/path/to/directory") do |response|
  raise "fail!" unless response.ok?
  sftp.close(response[:handle])
end
sftp.loop
# File lib/net/sftp/session.rb, line 405
def opendir(path, &callback)
  request :opendir, path, &callback
end
opendir!(path, &callback) click to toggle source

Identical to opendir, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return a handle to the given path.

handle = sftp.opendir!("/path/to/directory")
# File lib/net/sftp/session.rb, line 414
def opendir!(path, &callback)
  wait_for(opendir(path, &callback), :handle)
end
opening?() click to toggle source

Returns true if the connection is in the process of being initialized (e.g., it is not closed, but is not yet fully open).

# File lib/net/sftp/session.rb, line 745
def opening?
  !(open? || closed?)
end
read(handle, offset, length) → request click to toggle source
read(handle, offset, length) { |response| ... } → request

Requests that length bytes, starting at offset bytes from the beginning of the file, be read from the file identified by handle. (The handle should be a value obtained via the open method.) Returns immediately with a Request object. If a block is given, it will be invoked when the server responds.

The :data property of the response will contain the requested data, assuming the call was successful.

request = sftp.read(handle, 0, 1024) do |response|
  if response.eof?
    puts "end of file reached before reading any data"
  elsif !response.ok?
    puts "error (#{response})"
  else
    print(response[:data])
  end
end
request.wait

To read an entire file will usually require multiple calls to read, unless you know in advance how large the file is.

# File lib/net/sftp/session.rb, line 246
def read(handle, offset, length, &callback)
  request :read, handle, offset, length, &callback
end
read!(handle, offset, length, &callback) click to toggle source

Identical to read, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. If the end of the file was reached, nil will be returned. Otherwise, it returns the data that was read, as a String.

data = sftp.read!(handle, 0, 1024)
# File lib/net/sftp/session.rb, line 256
def read!(handle, offset, length, &callback)
  wait_for(read(handle, offset, length, &callback), :data)
end
readdir(handle) → request click to toggle source
raeddir(handle) { |response| ... } → request

Reads a set of entries from the given directory handle (which must have been obtained via opendir). If the response is EOF, then there are no more entries in the directory. Otherwise, the entries will be in the :names property of the response:

loop do
  request = sftp.readdir(handle).wait
  break if request.response.eof?
  raise "fail!" unless request.response.ok?
  request.response[:names].each do |entry|
     puts entry.name
  end
end

See also Protocol::V01::Name and Protocol::V04::Name for the specific properties of each individual entry (which vary based on the SFTP protocol version in use).

# File lib/net/sftp/session.rb, line 439
def readdir(handle, &callback)
  request :readdir, handle, &callback
end
readdir!(handle, &callback) click to toggle source

Identical to readdir, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return nil if there were no more names to read, or an array of name entries.

while (entries = sftp.readdir!(handle)) do
  entries.each { |entry| puts(entry.name) }
end
# File lib/net/sftp/session.rb, line 451
def readdir!(handle, &callback)
  wait_for(readdir(handle, &callback), :names)
end
realpath(path) → request click to toggle source
realpath(path) { |response| ... } → request

Tries to canonicalize the given path, turning any given path into an absolute path. This is primarily useful for converting a path with “..” or “.” segments into an identical path without those segments. The answer will be in the response's :names attribute, as a one-element array.

request = sftp.realpath("/path/../to/../directory").wait
puts request[:names].first.name
# File lib/net/sftp/session.rb, line 534
def realpath(path, &callback)
  request :realpath, path, &callback
end
realpath!(path, &callback) click to toggle source

Identical to realpath, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return a name object identifying the path.

puts(sftp.realpath!("/path/../to/../directory"))
# File lib/net/sftp/session.rb, line 543
def realpath!(path, &callback)
  wait_for(realpath(path, &callback), :names).first
end
remove(filename) → request click to toggle source
remove(filename) { |response| ... } → request

Attempts to remove the given file from the remote file system. Returns immediately with a Request object. If a block is given, the block will be invoked when the server responds, and will be passed a Response object.

sftp.remove("/path/to/file").wait
# File lib/net/sftp/session.rb, line 465
def remove(filename, &callback)
  request :remove, filename, &callback
end
remove!(filename, &callback) click to toggle source

Identical to remove, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

sftp.remove!("/path/to/file")
# File lib/net/sftp/session.rb, line 474
def remove!(filename, &callback)
  wait_for(remove(filename, &callback))
end
rename(name, new_name, flags=nil) → request click to toggle source
rename(name, new_name, flags=nil) { |response| ... } → request

Renames the given file. This operation is only available in SFTP protocol versions two and higher. The flags parameter is ignored in versions prior to 5. In versions 5 and higher, the flags parameter can be used to specify how the rename should be performed (atomically, etc.).

The following flags are defined in protocol version 5:

  • 0x0001 - overwrite an existing file if the new name specifies a file that already exists.

  • 0x0002 - perform the rewrite atomically.

  • 0x0004 - allow the server to perform the rename as it prefers.

# File lib/net/sftp/session.rb, line 580
def rename(name, new_name, flags=nil, &callback)
  request :rename, name, new_name, flags, &callback
end
rename!(name, new_name, flags=nil, &callback) click to toggle source

Identical to rename, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

sftp.rename!("/path/to/old", "/path/to/new")
# File lib/net/sftp/session.rb, line 589
def rename!(name, new_name, flags=nil, &callback)
  wait_for(rename(name, new_name, flags, &callback))
end
rmdir(path) → request click to toggle source
rmdir(path) { |response| ... } → request

Removes the named directory on the remote server. The directory must be empty before it can be removed.

sftp.rmdir("/path/to/directory").wait
# File lib/net/sftp/session.rb, line 509
def rmdir(path, &callback)
  request :rmdir, path, &callback
end
rmdir!(path, &callback) click to toggle source

Identical to rmdir, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

sftp.rmdir!("/path/to/directory")
# File lib/net/sftp/session.rb, line 518
def rmdir!(path, &callback)
  wait_for(rmdir(path, &callback))
end
send_packet(type, *args) click to toggle source

Formats, constructs, and sends an SFTP packet of the given type and with the given data. This does not block, but merely enqueues the packet for sending and returns.

You should probably use the operation methods, rather than building and sending the packet directly. (See open, close, etc.)

# File lib/net/sftp/session.rb, line 811
def send_packet(type, *args)
  data = Net::SSH::Buffer.from(*args)
  msg = Net::SSH::Buffer.from(:long, data.length+1, :byte, type, :raw, data)
  channel.send_data(msg.to_s)
end
setstat(path, attrs) → request click to toggle source
setstat(path, attrs) { |response| ... } → request

This method may be used to set file metadata (such as permissions, or user/group information) on a remote file. The exact metadata that may be tweaked is dependent on the SFTP protocol version in use, but in general you may set at least the permissions, user, and group. (See Protocol::V01::Attributes, Protocol::V04::Attributes, and Protocol::V06::Attributes for the full lists of attributes that may be set for the different protocols.)

The attrs parameter is a hash, where the keys are symbols identifying the attributes to set.

The method returns immediately with a Request object. If a block is given, it will be invoked when the server responds.

request = sftp.setstat("/path/to/file", :permissions => 0644)
request.wait
puts "success: #{request.response.ok?}"
# File lib/net/sftp/session.rb, line 361
def setstat(path, attrs, &callback)
  request :setstat, path, attrs, &callback
end
setstat!(path, attrs, &callback) click to toggle source

Identical to the setstat method, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

sftp.setstat!("/path/to/file", :permissions => 0644)
# File lib/net/sftp/session.rb, line 370
def setstat!(path, attrs, &callback)
  wait_for(setstat(path, attrs, &callback))
end
stat(path, flags=nil, &callback) click to toggle source

Identical to the lstat method, except that it follows symlinks (e.g., if you give it the path to a symlink, it will stat the target of the symlink rather than the symlink itself). See the lstat method for full documentation.

# File lib/net/sftp/session.rb, line 551
def stat(path, flags=nil, &callback)
  request :stat, path, flags, &callback
end
stat!(path, flags=nil, &callback) click to toggle source

Identical to stat, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return an attribute object for the named path.

attrs = sftp.stat!("/path/to/file")
# File lib/net/sftp/session.rb, line 560
def stat!(path, flags=nil, &callback)
  wait_for(stat(path, flags, &callback), :attrs)
end
unblock(handle, offset, length) → request click to toggle source
unblock(handle, offset, length) { |response| ... } → request

Removes a previously created byte-range lock. This operation is only available in protocol versions 6 and higher. The offset and length parameters must exactly match those that were given to block when the lock was acquired.

# File lib/net/sftp/session.rb, line 710
def unblock(handle, offset, length, &callback)
  request :unblock, handle, offset, length, &callback
end
unblock!(handle, offset, length, &callback) click to toggle source

Identical to unblock, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Response object for the request.

# File lib/net/sftp/session.rb, line 717
def unblock!(handle, offset, length, &callback)
  wait_for(unblock(handle, offset, length, &callback))
end
upload(local, remote = File.basename(local), options={}, &block) click to toggle source

Initiates an upload from local to remote, asynchronously. This method will return a new Net::SFTP::Operations::Upload instance, and requires the event loop to be run in order for the upload to progress. See Net::SFTP::Operations::Upload for a full discussion of how this method can be used.

uploader = sftp.upload("/local/path", "/remote/path")
uploader.wait
# File lib/net/sftp/session.rb, line 97
def upload(local, remote = File.basename(local), options={}, &block)
  Operations::Upload.new(self, local, remote, options, &block)
end
upload!(local, remote = File.basename(local), options={}, &block) click to toggle source

Identical to upload, but blocks until the upload is complete.

# File lib/net/sftp/session.rb, line 102
def upload!(local, remote = File.basename(local), options={}, &block)
  upload(local, remote, options, &block).wait
end
write(handle, offset, data) → request click to toggle source
write(handle, offset, data) { |response| ... } → request

Requests that data be written to the file identified by handle, starting at offset bytes from the start of the file. The file must have been opened for writing via open. Returns immediately with a Request object. If a block is given, it will be invoked when the server responds.

request = sftp.write(handle, 0, "hello, world!\n")
request.wait
# File lib/net/sftp/session.rb, line 272
def write(handle, offset, data, &callback)
  request :write, handle, offset, data, &callback
end
write!(handle, offset, data, &callback) click to toggle source

Identical to write, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful, or the end of the file was reached. Otherwise, it returns the Response object for this request.

sftp.write!(handle, 0, "hello, world!\n")
# File lib/net/sftp/session.rb, line 281
def write!(handle, offset, data, &callback)
  wait_for(write(handle, offset, data, &callback))
end

Private Instance Methods

dispatch_request(packet) click to toggle source

Parses the packet, finds the associated Request instance, and tells the Request instance to respond to the packet (see Request#respond_to).

# File lib/net/sftp/session.rb, line 945
def dispatch_request(packet)
  id = packet.read_long
  request = pending_requests.delete(id) or raise Net::SFTP::Exception, "no such request `#{id}'"
  request.respond_to(packet)
end
do_version(packet) click to toggle source

Called to handle FXP_VERSION packets. This performs the SFTP protocol version negotiation, instantiating the appropriate Protocol instance and invoking the callback given to connect, if any.

# File lib/net/sftp/session.rb, line 919
def do_version(packet)
  debug { "negotiating sftp protocol version, mine is #{HIGHEST_PROTOCOL_VERSION_SUPPORTED}" }

  server_version = packet.read_long
  debug { "server reports sftp version #{server_version}" }

  negotiated_version = [server_version, HIGHEST_PROTOCOL_VERSION_SUPPORTED].min
  info { "negotiated version is #{negotiated_version}" }

  extensions = {}
  until packet.eof?
    name = packet.read_string
    data = packet.read_string
    extensions[name] = data
  end

  @protocol = Protocol.load(self, negotiated_version)
  @pending_requests = {}

  @state = :open
  @on_ready.each { |callback| callback.call(self) }
  @on_ready = nil
end
input() click to toggle source

The input buffer used to accumulate packet data

# File lib/net/sftp/session.rb, line 824
def input; @input; end
request(type, *args, &callback) click to toggle source

Create and enqueue a new SFTP request of the given type, with the given arguments. Returns a new Request instance that encapsulates the request.

# File lib/net/sftp/session.rb, line 829
def request(type, *args, &callback)
  request = Request.new(self, type, protocol.send(type, *args), &callback)
  info { "sending #{type} packet (#{request.id})" }
  pending_requests[request.id] = request
end
wait_for(request, property=nil) click to toggle source

Waits for the given request to complete. If the response is EOF, nil is returned. If the response was not successful (e.g., !response.ok?), a StatusException will be raised. If property is given, the corresponding property from the response will be returned; otherwise, the response object itself will be returned.

# File lib/net/sftp/session.rb, line 841
def wait_for(request, property=nil)
  request.wait
  if request.response.eof?
    nil
  elsif !request.response.ok?
    raise StatusException.new(request.response)
  elsif property
    request.response[property.to_sym]
  else
    request.response
  end
end
when_channel_closed(channel) click to toggle source

Called when the SSH server closes the underlying channel.

# File lib/net/sftp/session.rb, line 883
def when_channel_closed(channel)
  debug { "sftp channel closed" }
  @channel = nil
  @state = :closed
end
when_channel_confirmed(channel) click to toggle source

Called when the SSH channel is confirmed as “open” by the server. This is one of the states of the SFTP state machine, and is followed by the when_subsystem_started state.

# File lib/net/sftp/session.rb, line 857
def when_channel_confirmed(channel)
  debug { "requesting sftp subsystem" }
  @state = :subsystem
  channel.subsystem("sftp", &method(:when_subsystem_started))
end
when_channel_polled(channel) click to toggle source

Called whenever Net::SSH polls the SFTP channel for pending activity. This basically checks the input buffer to see if enough input has been accumulated to handle. If there has, the packet is parsed and dispatched, according to its type (see do_version and dispatch_request).

# File lib/net/sftp/session.rb, line 893
def when_channel_polled(channel)
  while input.length > 0
    if @packet_length.nil?
      # make sure we've read enough data to tell how long the packet is
      return unless input.length >= 4
      @packet_length = input.read_long
    end

    return unless input.length >= @packet_length + 4
    packet = Net::SFTP::Packet.new(input.read(@packet_length))
    input.consume!
    @packet_length = nil

    debug { "received sftp packet #{packet.type} len #{packet.length}" }

    if packet.type == FXP_VERSION
      do_version(packet)
    else
      dispatch_request(packet)
    end
  end
end
when_subsystem_started(channel, success) click to toggle source

Called when the SSH server confirms that the SFTP subsystem was successfully started. This sets up the appropriate callbacks on the SSH channel and then starts the SFTP protocol version negotiation process.

# File lib/net/sftp/session.rb, line 867
def when_subsystem_started(channel, success)
  raise Net::SFTP::Exception, "could not start SFTP subsystem" unless success

  debug { "sftp subsystem successfully started" }
  @state = :init

  channel.on_data { |c,data| input.append(data) }
  channel.on_extended_data { |c,t,data| debug { data } }

  channel.on_close(&method(:when_channel_closed))
  channel.on_process(&method(:when_channel_polled))

  send_packet(FXP_INIT, :long, HIGHEST_PROTOCOL_VERSION_SUPPORTED)
end