Class: U3dCore::CommandExecutor

Inherits:
Object
  • Object
show all
Defined in:
lib/u3d_core/command_executor.rb

Overview

Executes commands and takes care of error handling and more

Class Method Summary collapse

Class Method Details

.execute(command: nil, print_all: false, print_command: true, error: nil, prefix: nil, loading: nil, admin: false) ⇒ String

Returns All the output as string.

Parameters:

  • command (String) (defaults to: nil) —

    The command to be executed

  • print_all (Boolean) (defaults to: false) —

    Do we want to print out the command output while running?

  • print_command (Boolean) (defaults to: true) —

    Should we print the command that’s being executed

  • error (Block) (defaults to: nil) —

    A block that’s called if an error occurs

  • prefix (Array) (defaults to: nil) —

    An array containg a prefix + block which might get applied to the output

  • loading (String) (defaults to: nil) —

    A loading string that is shown before the first output

  • admin (Boolean) (defaults to: false) —

    Do we need admin privilege for this command?

  • keychain (Boolean) —

    Should we fetch admin rights from the keychain on OSX

Returns:

  • (String) —

    All the output as string



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# File 'lib/u3d_core/command_executor.rb', line 60

def execute(command: nil, print_all: false, print_command: true, error: nil, prefix: nil, loading: nil, admin: false)
  print_all = true if U3dCore::Globals.verbose?
  prefix ||= {}

  output = []
  command = command.join(' ') if command.is_a?(Array)
  UI.command(command) if print_command

  # this is only used to show the "Loading text"...
  UI.command_output(loading) if print_all && loading

  if admin
    cred = U3dCore::Credentials.new(user: ENV['USER'])
    if Helper.windows?
      raise CredentialsError, "The command \'#{command}\' must be run in administrative shell" unless has_admin_privileges?
    else
      command = "sudo -k && echo #{cred.password.shellescape} | sudo -S " + command
    end
    UI.verbose 'Admin privileges granted for command execution'
  end

  begin
    status = U3dCore::Runner.run(command) do |stdin, _stdout, _pid|
      stdin.each do |l|
        line = l.strip # strip so that \n gets removed
        output << line

        next unless print_all

        # Prefix the current line with a string
        prefix.each do |element|
          line = element[:prefix] + line if element[:block] && element[:block].call(line)
        end

        UI.command_output(line)
      end
    end
    raise "Exit status: #{status}".red if status.nonzero? && !status.nil?
  rescue => ex
    # This could happen
    # * if the status is failed
    # * when the environment is wrong:
    # > invalid byte sequence in US-ASCII (ArgumentError)
    output << ex.to_s
    o = output.join("\n")
    UI.verbose o
    raise ex unless error
    error.call(o, nil)
  end
  return output.join("\n")
end

.has_admin_privileges? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/u3d_core/command_executor.rb', line 112

def has_admin_privileges?
  if Helper.windows?
    begin
      result = system('reg query HKU\\S-1-5-19', out: File::NULL, err: File::NULL)
    rescue
      result = false
    end
  else
    credentials = U3dCore::Credentials.new(user: ENV['USER'])
    begin
      # FIXME: hide / show output
      result = system("sudo -k && echo #{credentials.password.shellescape} | sudo -S /usr/bin/whoami")
    rescue
      result = false
    end
    credentials.forget_credentials unless result # FIXME: why?
  end
  # returns false if result is nil (command execution fail)
  return (result ? true : false)
end

.which(cmd) ⇒ Object

Cross-platform way of finding an executable in the $PATH. Respects the $PATHEXT, which lists valid file extensions for executables on Windows.

which('ruby') #=> /usr/bin/ruby

Derived from stackoverflow.com/a/5471032/3005



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# File 'lib/u3d_core/command_executor.rb', line 36

def which(cmd)
  # PATHEXT contains the list of file extensions that Windows considers executable, semicolon separated.
  # e.g. ".COM;.EXE;.BAT;.CMD"
  exts = ENV['PATHEXT'] ? ENV['PATHEXT'].split(';') : ['']

  ENV['PATH'].split(File::PATH_SEPARATOR).each do |path|
    exts.each do |ext|
      cmd_path = File.expand_path("#{cmd}#{ext}", path)
      return cmd_path if File.executable?(cmd_path) && !File.directory?(cmd_path)
    end
  end

  return nil
end