Class: CmdRunner::Command

Inherits:
Object
  • Object
show all
Defined in:
lib/cmd_runner.rb

Overview

Class: Command

Runs a command and grabs STDOUT, STDERR. Checks exit status to raise an exception in case of non-zero.

Example:

runner = CmdRunner::Command.new
runner.work_dir = '/tmp'   # to change dir before every command
runner.logger = Logger.new # to log command results
runner.execute!('ls')      #=> [0, '.\n..\n', '']

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#cmd ⇒ Object 



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# File 'lib/cmd_runner.rb', line 26

def cmd
  if self.work_dir.to_s.empty?
    @cmd
  else
    "cd #{self.work_dir} && " + @cmd
  end
end

#logger=(value) ⇒ Object

Logger to output command results



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# File 'lib/cmd_runner.rb', line 22

def logger=(value)
  @logger = value
end

#work_dir ⇒ Object

Change directory before each command



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# File 'lib/cmd_runner.rb', line 20

def work_dir
  @work_dir
end

Instance Method Details

#execute! ⇒ Object

Executes command.

Raises:

- {RuntimeError} if command returned non-zero status

Returns Array with exit status, stdout, stderr



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# File 'lib/cmd_runner.rb', line 40

def execute!
  result = ''
  error  = ''

  stdin, stdout, stderr, wait_thr = Open3.popen3(self.cmd)
  exit_status = wait_thr.value.exitstatus
  result << stdout.read
  error  << stderr.read

  raise "Command exited with non zero status: #{self.cmd}" unless exit_status.zero?
  [exit_status, result, error]
ensure
  logger.info   '-'*25
  logger.info   "Command: #{self.cmd}"
  logger.info   result
  logger.error  error
  logger.info   '-'*25
end