module ZTK::SSH::Exec
Public Instance Methods
exec(command, options={})
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Executes a command on the remote host.
@param [String] command The command to execute. @param [Hash] options The options hash for executing the command. @option options [Integer] :timeout (600) How long in seconds before
the command will timeout.
@option options [Boolean] :ignore_exit_status (false) Whether or not
we should ignore the exit status of the the process we spawn. By default we do not ignore the exit status and throw an exception if it is non-zero.
@option options [Integer] :exit_code (0) The exit code we expect the
process to return. This is ignore if *ignore_exit_status* is true.
@option options [Boolean] :silence (false) Whether or not we should
squelch the output of the process. The output will always go to the logging device supplied in the ZTK::UI object. The output is always available in the return value from the method additionally.
@return [OpenStruct#output] The output of the command, both STDOUT and
STDERR.
@return [OpenStruct#exit] The exit status (i.e. $?).
@example Execute a command:
ssh = ZTK::SSH.new ssh.config do |config| config.user = ENV["USER"] config.host_name = "127.0.0.1" end puts ssh.exec("hostname").inspect
# File lib/ztk/ssh/exec.rb, line 36 def exec(command, options={}) options = OpenStruct.new(config.send(:table).merge(options)) options.ui.logger.debug { "config=#{config.send(:table).inspect}" } options.ui.logger.debug { "options=#{options.send(:table).inspect}" } options.ui.logger.info { "exec(#{command.inspect})" } output = "" exit_code = -1 exit_signal = nil stdout_header = false stderr_header = false begin raise_on_exceptions = [Timeout::Error] defined?(Resque) and raise_on_exceptions << Resque::TermException ZTK::RescueRetry.try( :ui => config.ui, :tries => ZTK::SSH::RESCUE_RETRY_ATTEMPTS, :raise => raise_on_exceptions, :on_retry => method(:on_retry) ) do Timeout.timeout(options.timeout) do channel = ssh.open_channel do |chan| options.ui.logger.debug { "Channel opened." } (options.request_pty == true) and chan.request_pty do |ch, success| if success options.ui.logger.debug { "PTY obtained." } else options.ui.logger.warn { "Could not obtain PTY." } end end direct_log(:info) { log_header("COMMAND") } direct_log(:info) { "#{command}\n" } direct_log(:info) { log_header("OPENED", "-") } chan.exec(command) do |ch, success| success or log_and_raise(SSHError, "Could not execute '#{command}'.") ch.on_data do |c, data| if !stdout_header direct_log(:info) { log_header("STDOUT", "-") } stdout_header = true stderr_header = false end direct_log(:info) { data } options.ui.stdout.print(data) unless options.silence output += data options.on_progress.nil? or options.on_progress.call end ch.on_extended_data do |c, type, data| if !stderr_header direct_log(:warn) { log_header("STDERR", "-") } stderr_header = true stdout_header = false end direct_log(:warn) { data } options.ui.stderr.print(data) unless options.silence output += data options.on_progress.nil? or options.on_progress.call end ch.on_request("exit-status") do |c, data| exit_code = data.read_long end ch.on_request("exit-signal") do |c, data| exit_signal = data.read_long end ch.on_open_failed do |c, code, desc| options.ui.logger.fatal { "Open failed! (#{code.inspect} - #{desc.inspect})" } end end end channel.wait direct_log(:info) { log_header("CLOSED") } options.ui.logger.debug { "Channel closed." } end end rescue Timeout::Error => e direct_log(:fatal) { log_header("TIMEOUT") } log_and_raise(SSHError, "Session timed out after #{options.timeout} seconds!") end message = [ "exit_code=#{exit_code}", (exit_signal.nil? ? nil : "exit_signal=#{exit_signal} (#{EXIT_SIGNALS[exit_signal]})") ].compact.join(", ") options.ui.logger.debug { message } if !options.ignore_exit_status && (exit_code != options.exit_code) log_and_raise(SSHError, message) end OpenStruct.new(:command => command, :output => output, :exit_code => exit_code, :exit_signal => exit_signal) end