Module: Sys

Extended by:
Sys
Included in:
Sys
Defined in:
lib/nub/sys.rb

Instance Method Summary collapse

Instance Method Details

#any_key? ⇒ Boolean

Wait for any key to be pressed

Returns:

  • (Boolean) 


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# File 'lib/nub/sys.rb', line 31

def any_key?
  begin
    state = `stty -g`
    `stty raw -echo -icanon isig`
    STDIN.getc.chr
  ensure
    `stty #{state}`
  end
end

#caller_filename ⇒ Object

Get the caller’s filename for the caller of the function this call is nested in not the function this call is called in



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# File 'lib/nub/sys.rb', line 44

def caller_filename
  path = caller_locations(2, 1).first.path
  return File.basename(path)
end

#capture ⇒ Object

Capture STDOUT to a string



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# File 'lib/nub/sys.rb', line 51

def capture
  stdout, stderr = StringIO.new, StringIO.new
  $stdout, $stderr = stdout, stderr

  result = Proc.new.call

  $stdout, $stderr = STDOUT, STDERR
  $stdout.flush
  $stderr.flush

  return OpenStruct.new(result: result, stdout: stdout.string, stderr: stderr.string)
end

#env(var, required: true) ⇒ Object

Get the given environment variable by nam

Parameters:

  • var (String) —

    name of the environment var

  • required (Bool) (defaults to: true) —

    require that the variable exists by default



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# File 'lib/nub/sys.rb', line 67

def env(var, required:true)
  value = ENV[var]
  Log.die("#{var} env variable is required!") if required && !value
  return value
end

#exec(cmd, env: {}, die: true) ⇒ Object

Run the system command in an exception wrapper

Parameters:

  • cmd (String/Array) —

    cmd to execute

  • env (Hash) (defaults to: {}) —

    optional environment variables to set

  • die (Bool) (defaults to: true) —

    fail on errors if true



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# File 'lib/nub/sys.rb', line 78

def exec(cmd, env:{}, die:true)
  result = false
  puts("exec: #{cmd.is_a?(String) ? cmd : cmd * ' '}")

  begin
    if cmd.is_a?(String)
      result = system(env, cmd, out: $stdout, err: :out)
    else
      result = system(env, *cmd, out: $stdout, err: :out)
    end
  rescue Exception => e
    result = false
    puts(e.message.colorize(:red))
    puts(e.backtrace.inspect.colorize(:red))
    exit if die
  end

  !puts("Error: failed to execute command properly".colorize(:red)) and
    exit unless !die or result

  return result
end

#getpass ⇒ Object

Read a password from stdin without echoing



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# File 'lib/nub/sys.rb', line 103

def getpass
  print("Enter Password: ")
  pass = STDIN.noecho(&:gets).strip
  puts
  return pass
end

#rm_rf(path) ⇒ Object

Remove given dir or file Params:

path

path to delete

returns

path that was deleted



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# File 'lib/nub/sys.rb', line 114

def rm_rf(path)
  Sys.exec("rm -rf #{path}")
  return path
end

#umount(mount, retries: 1) ⇒ Object

Unmount the given mount point Params:

mount

mount point to unmount

retries

number of times to retry



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# File 'lib/nub/sys.rb', line 123

def umount(mount, retries:1)
  check = ->(mnt){
    match = `mount`.split("\n").find{|x| x.include?(mnt)}
    match = match.split('overlay').first if match
    return (match and match.include?(mnt))
  }

  success = false
  while not success and retries > 0
    if check[mount]
      success = system('umount', '-fv', mount)
    else
      success = true
    end

    # Sleep for a second if failed
    sleep(1) and retries -= 1 unless success
  end

  # Die if still mounted
  !puts("Error: Failed to umount #{mount}".colorize(:red)) and
    exit if check[mount]
end