Class | Net::SFTP::Session |
In: |
lib/net/sftp/session.rb
|
Parent: | Object |
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.)
HIGHEST_PROTOCOL_VERSION_SUPPORTED | = | 6 | The highest protocol version supported by the Net::SFTP library. |
loop | -> | loop_forever |
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. |
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 78: def initialize(session, &block) 79: @session = session 80: @input = Net::SSH::Buffer.new 81: self.logger = session.logger 82: @state = :closed 83: 84: connect(&block) 85: end
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:
Once created, the lock may be removed via the unblock method.
# File lib/net/sftp/session.rb, line 690 690: def block(handle, offset, length, mask, &callback) 691: request :block, handle, offset, length, mask, &callback 692: end
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 697 697: def block!(handle, offset, length, mask, &callback) 698: wait_for(block(handle, offset, length, mask, &callback)) 699: end
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 206 206: def close(handle, &callback) 207: request :close, handle, &callback 208: end
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 215 215: def close!(handle, &callback) 216: wait_for(close(handle, &callback)) 217: end
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 726 726: def close_channel 727: return unless open? 728: channel.close 729: loop { !closed? } 730: end
Returns true if the connection has been closed.
# File lib/net/sftp/session.rb, line 738 738: def closed? 739: state == :closed 740: end
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 765 765: def connect(&block) 766: case state 767: when :open 768: block.call(self) if block 769: when :closed 770: @state = :opening 771: @channel = session.open_channel(&method(:when_channel_confirmed)) 772: @packet_length = nil 773: @protocol = nil 774: @on_ready = Array(block) 775: else # opening 776: @on_ready << block if block 777: end 778: 779: self 780: end
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 152 152: def dir 153: @dir ||= Operations::Dir.new(self) 154: end
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 114 114: def download(remote, local, options={}, &block) 115: Operations::Download.new(self, local, remote, options, &block) 116: end
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 122 122: def download!(remote, local=nil, options={}, &block) 123: destination = local || StringIO.new 124: result = download(remote, destination, options, &block).wait 125: local ? result : destination.string 126: end
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 139 139: def file 140: @file ||= Operations::FileFactory.new(self) 141: end
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 377 377: def fsetstat(handle, attrs, &callback) 378: request :fsetstat, handle, attrs, &callback 379: end
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 386 386: def fsetstat!(handle, attrs, &callback) 387: wait_for(fsetstat(handle, attrs, &callback)) 388: end
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 326 326: def fstat(handle, flags=nil, &callback) 327: request :fstat, handle, flags, &callback 328: end
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 335 335: def fstat!(handle, flags=nil, &callback) 336: wait_for(fstat(handle, flags, &callback), :attrs) 337: end
Attempts to create a link, either hard or symbolic. This operation is only available in SFTP protocol versions 6 and higher. If the symlink paramter is true, a symbolic link will be created, otherwise a hard link will be created. The link will be named new_link_path, and will point to the path existing_path.
sftp.link("/path/to/symlink", "/path/to/file", true).wait
Note that link is only available for SFTP protocol 6 and higher. You can use symlink for protocols 3 and higher.
# File lib/net/sftp/session.rb, line 653 653: def link(new_link_path, existing_path, symlink=true, &callback) 654: request :link, new_link_path, existing_path, symlink, &callback 655: end
Identical to link, 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.link!("/path/to/symlink", "/path/to/file", true)
# File lib/net/sftp/session.rb, line 662 662: def link!(new_link_path, existing_path, symlink=true, &callback) 663: wait_for(link(new_link_path, existing_path, symlink, &callback)) 664: end
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 799 799: def loop(&block) 800: block ||= Proc.new { pending_requests.any? } 801: session.loop(&block) 802: end
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 309 309: def lstat(path, flags=nil, &callback) 310: request :lstat, path, flags, &callback 311: end
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 318 318: def lstat!(path, flags=nil, &callback) 319: wait_for(lstat(path, flags, &callback), :attrs) 320: end
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 487 487: def mkdir(path, attrs={}, &callback) 488: request :mkdir, path, attrs, &callback 489: end
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 496 496: def mkdir!(path, attrs={}, &callback) 497: wait_for(mkdir(path, attrs, &callback)) 498: end
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 180 180: def open(path, flags="r", options={}, &callback) 181: request :open, path, flags, options, &callback 182: end
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 189 189: def open!(path, flags="r", options={}, &callback) 190: wait_for(open(path, flags, options, &callback), :handle) 191: end
Returns true if the connection has been initialized.
# File lib/net/sftp/session.rb, line 733 733: def open? 734: state == :open 735: end
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 404 404: def opendir(path, &callback) 405: request :opendir, path, &callback 406: end
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 413 413: def opendir!(path, &callback) 414: wait_for(opendir(path, &callback), :handle) 415: end
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 245 245: def read(handle, offset, length, &callback) 246: request :read, handle, offset, length, &callback 247: end
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 255 255: def read!(handle, offset, length, &callback) 256: wait_for(read(handle, offset, length, &callback), :data) 257: end
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 438 438: def readdir(handle, &callback) 439: request :readdir, handle, &callback 440: end
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 450 450: def readdir!(handle, &callback) 451: wait_for(readdir(handle, &callback), :names) 452: end
Queries the server for the target of the specified symbolic link. This operation is only available in protocol versions 3 and higher. The response to this request will include a names property, a one-element array naming the target of the symlink.
request = sftp.readlink("/path/to/symlink").wait puts request.response[:names].first.name
# File lib/net/sftp/session.rb, line 603 603: def readlink(path, &callback) 604: request :readlink, path, &callback 605: end
Identical to readlink, but blocks until the server responds. It will raise a StatusException if the request was unsuccessful. Otherwise, it will return the Name object for the path that the symlink targets.
item = sftp.readlink!("/path/to/symlink")
# File lib/net/sftp/session.rb, line 612 612: def readlink!(path, &callback) 613: wait_for(readlink(path, &callback), :names).first 614: end
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 533 533: def realpath(path, &callback) 534: request :realpath, path, &callback 535: end
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 542 542: def realpath!(path, &callback) 543: wait_for(realpath(path, &callback), :names).first 544: end
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 464 464: def remove(filename, &callback) 465: request :remove, filename, &callback 466: end
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 473 473: def remove!(filename, &callback) 474: wait_for(remove(filename, &callback)) 475: end
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:
# File lib/net/sftp/session.rb, line 579 579: def rename(name, new_name, flags=nil, &callback) 580: request :rename, name, new_name, flags, &callback 581: end
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 588 588: def rename!(name, new_name, flags=nil, &callback) 589: wait_for(rename(name, new_name, flags, &callback)) 590: end
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 508 508: def rmdir(path, &callback) 509: request :rmdir, path, &callback 510: end
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 517 517: def rmdir!(path, &callback) 518: wait_for(rmdir(path, &callback)) 519: end
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 810 810: def send_packet(type, *args) 811: data = Net::SSH::Buffer.from(*args) 812: msg = Net::SSH::Buffer.from(:long, data.length+1, :byte, type, :raw, data) 813: channel.send_data(msg.to_s) 814: end
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 360 360: def setstat(path, attrs, &callback) 361: request :setstat, path, attrs, &callback 362: end
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 369 369: def setstat!(path, attrs, &callback) 370: wait_for(setstat(path, attrs, &callback)) 371: end
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 550 550: def stat(path, flags=nil, &callback) 551: request :stat, path, flags, &callback 552: end
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 559 559: def stat!(path, flags=nil, &callback) 560: wait_for(stat(path, flags, &callback), :attrs) 561: end
Attempts to create a symlink to path at target. This operation is only available in protocol versions 3, 4, and 5, but the Net::SFTP library mimics the symlink behavior in protocol version 6 using the link method, so it is safe to use this method in protocol version 6.
sftp.symlink("/path/to/file", "/path/to/symlink").wait
# File lib/net/sftp/session.rb, line 626 626: def symlink(path, target, &callback) 627: request :symlink, path, target, &callback 628: end
Identical to symlink, 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.symlink!("/path/to/file", "/path/to/symlink")
# File lib/net/sftp/session.rb, line 635 635: def symlink!(path, target, &callback) 636: wait_for(symlink(path, target, &callback)) 637: end
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 709 709: def unblock(handle, offset, length, &callback) 710: request :unblock, handle, offset, length, &callback 711: end
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 716 716: def unblock!(handle, offset, length, &callback) 717: wait_for(unblock(handle, offset, length, &callback)) 718: end
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 97: def upload(local, remote, options={}, &block) 98: Operations::Upload.new(self, local, remote, options, &block) 99: end
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 271 271: def write(handle, offset, data, &callback) 272: request :write, handle, offset, data, &callback 273: end
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 280 280: def write!(handle, offset, data, &callback) 281: wait_for(write(handle, offset, data, &callback)) 282: end