Class: Kitchen::Transport::Ssh::Connection

Inherits:
Base::Connection show all
Defined in:
lib/kitchen/transport/ssh.rb

Overview

A Connection instance can be generated and re-generated, given new connection details such as connection port, hostname, credentials, etc. This object is responsible for carrying out the actions on the remote host such as executing commands, transferring files, etc.

Author:

Instance Method Summary collapse

Methods inherited from Base::Connection

#execute_with_retry, #retry?

Methods included from Logging

#banner, #debug, #error, #fatal, #info, #warn

Constructor Details

#initialize(config = {}) {|self| ... } ⇒ Object

Create a new Connection instance.

Yields:

  • (self) —

    yields itself for block-style invocation



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# File 'lib/kitchen/transport/ssh.rb', line 125

def initialize(config = {})
  super(config)
  @session = nil
end

Instance Method Details

#close ⇒ Object

Closes the session connection, if it is still active.



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# File 'lib/kitchen/transport/ssh.rb', line 131

def close
  return if @session.nil?

  string_to_mask = "[SSH] closing connection to #{self}"
  masked_string = Util.mask_values(string_to_mask, %w{password ssh_http_proxy_password})
  logger.debug(masked_string)
  session.close
ensure
  @session = nil
end

#download(remotes, local) ⇒ Object

Download remote files or directories to local host.

Raises:

  • (TransportFailed) —

    if the files could not all be downloaded successfully, which may vary by implementation



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# File 'lib/kitchen/transport/ssh.rb', line 207

def download(remotes, local)
  # ensure the parent dir of the local target exists
  FileUtils.mkdir_p(File.dirname(local))

  Array(remotes).each do |file|
    logger.debug("Attempting to download '#{file}' as file")
    session.scp.download!(file, local)
  rescue Net::SCP::Error
    begin
      logger.debug("Attempting to download '#{file}' as directory")
      session.scp.download!(file, local, recursive: true)
    rescue Net::SCP::Error
      logger.warn(
        "SCP download failed for file or directory '#{file}', perhaps it does not exist?"
      )
    end
  end
rescue Net::SSH::Exception => ex
  raise SshFailed, "SCP download failed (#{ex.message})"
end

#execute(command) ⇒ Object

Execute a command on the remote host.

Raises:

  • (TransportFailed) —

    if the command does not exit successfully, which may vary by implementation



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# File 'lib/kitchen/transport/ssh.rb', line 143

def execute(command)
  return if command.nil?

  string_to_mask = "[SSH] #{self} (#{command})"
  masked_string = Util.mask_values(string_to_mask, %w{password ssh_http_proxy_password})
  logger.debug(masked_string)
  exit_code = execute_with_exit_code(command)

  if exit_code != 0
    raise Transport::SshFailed.new(
      "SSH exited (#{exit_code}) for command: [#{command}]",
      exit_code
    )
  end
rescue Net::SSH::Exception => ex
  raise SshFailed, "SSH command failed (#{ex.message})"
end

#login_command ⇒ LoginCommand

Builds a LoginCommand which can be used to open an interactive session on the remote host.

Raises:



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# File 'lib/kitchen/transport/ssh.rb', line 162

def 
  args  = %w{ -o UserKnownHostsFile=/dev/null }
  args += %w{ -o StrictHostKeyChecking=no }
  args += %w{ -o IdentitiesOnly=yes } if options[:keys]
  args += %W{ -o LogLevel=#{logger.debug? ? "VERBOSE" : "ERROR"} }
  if options.key?(:forward_agent)
    args += %W{ -o ForwardAgent=#{options[:forward_agent] ? "yes" : "no"} }
  end
  if ssh_proxy_command
    args += %W{ -o ProxyCommand=#{ssh_proxy_command} }
  elsif ssh_gateway
    gateway_command = "ssh -q #{ssh_gateway_username}@#{ssh_gateway} nc #{hostname} #{port}"
    args += %W{ -o ProxyCommand=#{gateway_command} -p #{ssh_gateway_port} }
  end
  Array(options[:keys]).each { |ssh_key| args += %W{ -i #{ssh_key} } }
  args += %W{ -p #{port} }
  args += %W{ #{username}@#{hostname} }

  LoginCommand.new("ssh", args)
end

#upload(locals, remote) ⇒ Object

Uploads local files or directories to remote host.

Raises:

  • (TransportFailed) —

    if the files could not all be uploaded successfully, which may vary by implementation



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# File 'lib/kitchen/transport/ssh.rb', line 184

def upload(locals, remote)
  logger.debug("TIMING: scp async upload (Kitchen::Transport::Ssh)")
  elapsed = Benchmark.measure do
    waits = []
    Array(locals).map do |local|
      opts = File.directory?(local) ? { recursive: true } : {}

      waits.push(
        session.scp.upload(local, remote, opts) do |_ch, name, sent, total|
          logger.debug("Async Uploaded #{name} (#{total} bytes)") if sent == total
        end
      )
      waits.shift.wait while waits.length >= max_ssh_sessions
    end
    waits.each(&:wait)
  end
  delta = Util.duration(elapsed.real)
  logger.debug("TIMING: scp async upload (Kitchen::Transport::Ssh) took #{delta}")
rescue Net::SSH::Exception => ex
  raise SshFailed, "SCP upload failed (#{ex.message})"
end

#wait_until_ready ⇒ Object

Block and return only when the remote host is prepared and ready to execute command and upload files. The semantics and details will vary by implementation, but a round trip through the hosted service is preferred to simply waiting on a socket to become available.



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# File 'lib/kitchen/transport/ssh.rb', line 229

def wait_until_ready
  delay = 3
  session(
    retries: max_wait_until_ready / delay,
    delay:,
    message: "Waiting for SSH service on #{hostname}:#{port}, " \
      "retrying in #{delay} seconds"
  )
  execute(PING_COMMAND.dup)
end