Class: Aspera::Cli::Manager

Inherits:
Object
  • Object
show all
Defined in:
lib/aspera/cli/manager.rb

Overview

parse command line options arguments options start with ‘-’, others are commands resolves on extended value syntax

Constant Summary collapse

BOOLEAN_SIMPLE =

boolean options are set to true/false from the following values

%i[no yes].freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(program_name) ⇒ Manager

Returns a new instance of Manager.



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# File 'lib/aspera/cli/manager.rb', line 117

def initialize(program_name)
  # command line values not starting with '-'
  @unprocessed_cmd_line_arguments = []
  # command line values starting with '-'
  @unprocessed_cmd_line_options = []
  # a copy of all initial options
  @initial_cli_options = []
  # option description: key = option symbol, value=hash, :read_write, :accessor, :value, :accepted
  @declared_options = {}
  # do we ask missing options and arguments to user ?
  @ask_missing_mandatory = false # STDIN.isatty
  # ask optional options if not provided and in interactive
  @ask_missing_optional = false
  @fail_on_missing_mandatory = true
  # those must be set before parse, parse consumes those defined only
  @unprocessed_defaults = []
  @unprocessed_env = []
  # NOTE: was initially inherited but it is preferred to have specific methods
  @parser = OptionParser.new
  @parser.program_name = program_name
  # options can also be provided by env vars : --param-name -> ASCLI_PARAM_NAME
  env_prefix = program_name.upcase + OPTION_SEP_SYMBOL
  ENV.each do |k, v|
    if k.start_with?(env_prefix)
      @unprocessed_env.push([k[env_prefix.length..-1].downcase.to_sym, v])
    end
  end
  Log.log.debug{"env=#{@unprocessed_env}".red}
  @unprocessed_cmd_line_options = []
  @unprocessed_cmd_line_arguments = []
end

Instance Attribute Details

#ask_missing_mandatory ⇒ Object

Returns the value of attribute ask_missing_mandatory.



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# File 'lib/aspera/cli/manager.rb', line 114

def ask_missing_mandatory
  @ask_missing_mandatory
end

#ask_missing_optional ⇒ Object

Returns the value of attribute ask_missing_optional.



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# File 'lib/aspera/cli/manager.rb', line 114

def ask_missing_optional
  @ask_missing_optional
end

#fail_on_missing_mandatory=(value) ⇒ Object (writeonly)

Sets the attribute fail_on_missing_mandatory

Parameters:

  • value —

    the value to set the attribute fail_on_missing_mandatory to.



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# File 'lib/aspera/cli/manager.rb', line 115

def fail_on_missing_mandatory=(value)
  @fail_on_missing_mandatory = value
end

#parser ⇒ Object (readonly)

Returns the value of attribute parser.



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# File 'lib/aspera/cli/manager.rb', line 113

def parser
  @parser
end

Class Method Details

.enum_to_bool(enum) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 63

def enum_to_bool(enum)
  Aspera.assert_values(enum, BOOLEAN_VALUES){'boolean'}
  return TRUE_VALUES.include?(enum)
end

.get_from_list(short_value, descr, allowed_values) ⇒ Object

find shortened string value in allowed symbol list



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# File 'lib/aspera/cli/manager.rb', line 73

def get_from_list(short_value, descr, allowed_values)
  # we accept shortcuts
  matching_exact = allowed_values.select{|i| i.to_s.eql?(short_value)}
  return matching_exact.first if matching_exact.length == 1
  matching = allowed_values.select{|i| i.to_s.start_with?(short_value)}
  multi_choice_assert(!matching.empty?, "unknown value for #{descr}: #{short_value}", allowed_values)
  multi_choice_assert(matching.length.eql?(1), "ambiguous shortcut for #{descr}: #{short_value}", matching)
  return enum_to_bool(matching.first) if allowed_values.eql?(BOOLEAN_VALUES)
  return matching.first
end

.multi_choice_assert(assertion, error_msg, choices) ⇒ Object

Generates error message with list of allowed values

Parameters:

  • error_msg (String) —

    error message

  • choices (Array) —

    list of allowed values

Raises:



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# File 'lib/aspera/cli/manager.rb', line 87

def multi_choice_assert(assertion, error_msg, choices)
  raise Cli::BadArgument, [error_msg, 'Use:'].concat(choices.map{|c|"- #{c}"}.sort).join("\n") unless assertion
end

.option_line_to_name(name) ⇒ Object

change option name with dash to name with underscore



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# File 'lib/aspera/cli/manager.rb', line 92

def option_line_to_name(name)
  return name.gsub(OPTION_SEP_LINE, OPTION_SEP_SYMBOL)
end

.option_name_to_line(name) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 96

def option_name_to_line(name)
  return "--#{name.to_s.gsub(OPTION_SEP_SYMBOL, OPTION_SEP_LINE)}"
end

.time_to_string(time) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 68

def time_to_string(time)
  return time.strftime('%Y-%m-%d %H:%M:%S')
end

.validate_type(what, descr, value, type_list) ⇒ Object

Parameters:

  • what (Symbol) —

    :option or :argument

  • descr (String) —

    description for help

  • value (Object) —

    value to check

  • type_list (NilClass, Class, Array[Class]) —

    accepted value type(s)

Raises:



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# File 'lib/aspera/cli/manager.rb', line 104

def validate_type(what, descr, value, type_list)
  return nil if type_list.nil?
  Aspera.assert(type_list.is_a?(Array) && type_list.all?(Class)){'types must be a Class Array'}
  raise Cli::BadArgument,
    "#{what.to_s.capitalize} #{descr} is a #{value.class} but must be #{type_list.length > 1 ? 'one of ' : ''}#{type_list.map(&:name).join(',')}" unless \
    type_list.any?{|t|value.is_a?(t)}
end

Instance Method Details

#add_option_preset(preset_hash, op: :push) ⇒ Object

Adds each of the keys of specified hash as an option

Parameters:

  • preset_hash (Hash) —

    hash of options to add



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# File 'lib/aspera/cli/manager.rb', line 371

def add_option_preset(preset_hash, op: :push)
  Aspera.assert_type(preset_hash, Hash)
  Log.log.debug{"add_option_preset=#{preset_hash}"}
  # incremental override
  preset_hash.each{|k, v|@unprocessed_defaults.send(op, [k.to_sym, v])}
end

#command_or_arg_empty? ⇒ Boolean

check if there were unprocessed values to generate error

Returns:

  • (Boolean) 


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# File 'lib/aspera/cli/manager.rb', line 379

def command_or_arg_empty?
  return @unprocessed_cmd_line_arguments.empty?
end

#declare(option_symbol, description, handler: nil, default: nil, values: nil, short: nil, coerce: nil, types: nil, deprecation: nil, &block) ⇒ Object

declare an option

Parameters:

  • option_symbol (Symbol) —

    option name

  • description (String) —

    description for help

  • handler (Hash) (defaults to: nil) —

    handler for option value: keys: o (object) and m (method)

  • default (Object) (defaults to: nil) —

    default value

  • values (nil, Array, :bool, :date, :none) (defaults to: nil) —

    list of allowed values, :bool for true/false, :date for dates, :none for on/off switch

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

    short option name

  • coerce (Class) (defaults to: nil) —

    one of the coerce types accepted par option parser

  • types (Class, Array) (defaults to: nil) —

    accepted value type(s)

  • block (Proc) —

    block to execute when option is found



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# File 'lib/aspera/cli/manager.rb', line 298

def declare(option_symbol, description, handler: nil, default: nil, values: nil, short: nil, coerce: nil, types: nil, deprecation: nil, &block)
  Aspera.assert(!@declared_options.key?(option_symbol)){"#{option_symbol} already declared"}
  Aspera.assert(description[-1] != '.'){"#{option_symbol} ends with dot"}
  Aspera.assert(description[0] == description[0].upcase){"#{option_symbol} description does not start with capital"}
  Aspera.assert(!['hash', 'extended value'].any?{|s|description.downcase.include?(s) }){"#{option_symbol} shall use :types"}
  opt = @declared_options[option_symbol] = {
    read_write: handler.nil? ? :value : :accessor,
    # by default passwords and secrets are sensitive, else specify when declaring the option
    sensitive:  SecretHider.secret?(option_symbol, '')
  }
  if !types.nil?
    types = [types] unless types.is_a?(Array)
    Aspera.assert(types.all?(Class)){"types must be Array of Class: #{types}"}
    opt[:types] = types
    description = "#{description} (#{types.map(&:name).join(', ')})"
  end
  if deprecation
    opt[:deprecation] = deprecation
    description = "#{description} (#{'deprecated'.blue}: #{deprecation})"
  end
  Log.log.debug{"declare: #{option_symbol}: #{opt[:read_write]}".green}
  if opt[:read_write].eql?(:accessor)
    Aspera.assert_type(handler, Hash)
    Aspera.assert(handler.keys.sort.eql?(%i[m o]))
    Log.log.debug{"set attr obj #{option_symbol} (#{handler[:o]},#{handler[:m]})"}
    opt[:accessor] = AttrAccessor.new(handler[:o], handler[:m], option_symbol)
  end
  set_option(option_symbol, default, 'default') unless default.nil?
  on_args = [description]
  case values
  when nil
    on_args.push(symbol_to_option(option_symbol, 'VALUE'))
    on_args.push("-#{short}VALUE") unless short.nil?
    on_args.push(coerce) unless coerce.nil?
    @parser.on(*on_args) { |v| set_option(option_symbol, v, SOURCE_USER) }
  when Array, :bool
    if values.eql?(:bool)
      values = BOOLEAN_VALUES
      set_option(option_symbol, Manager.enum_to_bool(default), 'default') unless default.nil?
    end
    # this option value must be a symbol
    opt[:values] = values
    value = get_option(option_symbol)
    help_values = values.map{|i|i.eql?(value) ? highlight_current(i) : i}.join(', ')
    if values.eql?(BOOLEAN_VALUES)
      help_values = BOOLEAN_SIMPLE.map{|i|(i.eql?(:yes) && value) || (i.eql?(:no) && !value) ? highlight_current(i) : i}.join(', ')
    end
    on_args[0] = "#{description}: #{help_values}"
    on_args.push(symbol_to_option(option_symbol, 'ENUM'))
    on_args.push(values)
    @parser.on(*on_args){|v|set_option(option_symbol, self.class.get_from_list(v.to_s, description, values), SOURCE_USER)}
  when :date
    on_args.push(symbol_to_option(option_symbol, 'DATE'))
    @parser.on(*on_args) do |v|
      time_string = case v
      when 'now' then Manager.time_to_string(Time.now)
      when /^-([0-9]+)h/ then Manager.time_to_string(Time.now - (Regexp.last_match(1).to_i * 3600))
      else v
      end
      set_option(option_symbol, time_string, SOURCE_USER)
    end
  when :none
    Aspera.assert(!block.nil?){"missing block for #{option_symbol}"}
    on_args.push(symbol_to_option(option_symbol, nil))
    on_args.push("-#{short}") if short.is_a?(String)
    @parser.on(*on_args, &block)
  else Aspera.error_unexpected_value(values)
  end
  Log.log.debug{"on_args=#{on_args}"}
end

#final_errors ⇒ Object

unprocessed options or arguments ?



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# File 'lib/aspera/cli/manager.rb', line 384

def final_errors
  result = []
  result.push("unprocessed options: #{@unprocessed_cmd_line_options}") unless @unprocessed_cmd_line_options.empty?
  result.push("unprocessed values: #{@unprocessed_cmd_line_arguments}") unless @unprocessed_cmd_line_arguments.empty?
  return result
end

#get_interactive(type, descr, expected: :single) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 471

def get_interactive(type, descr, expected: :single)
  if !@ask_missing_mandatory
    raise Cli::BadArgument, "missing argument (#{expected}): #{descr}" unless expected.is_a?(Array)
    self.class.multi_choice_assert(false, "missing: #{descr}", expected)
  end
  result = nil
  sensitive = type.eql?(:option) && @declared_options[descr.to_sym].is_a?(Hash) && @declared_options[descr.to_sym][:sensitive]
  default_prompt = "#{type}: #{descr}"
  # ask interactively
  case expected
  when :multiple
    result = []
    puts(' (one per line, end with empty line)')
    loop do
      entry = prompt_user_input(default_prompt, sensitive)
      break if entry.empty?
      result.push(ExtendedValue.instance.evaluate(entry))
    end
  when :single
    result = ExtendedValue.instance.evaluate(prompt_user_input(default_prompt, sensitive))
  else # one fixed
    result = self.class.get_from_list(prompt_user_input("#{expected.join(' ')}\n#{default_prompt}", sensitive), descr, expected)
  end
  return result
end

#get_next_argument(descr, expected: :single, mandatory: true, type: nil, aliases: nil, default: nil) ⇒ Object

Returns value, list or nil.

Parameters:

  • descr (String) —

    description for help

  • expected (defaults to: :single) —

    is

    • Array of allowed value (single value)

    • :multiple for remaining values

    • :single for a single unconstrained value

    • :integer for a single integer value

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

    if true, raise error if option not set

  • type (Class, Array) (defaults to: nil) —

    accepted value type(s)

  • aliases (Hash) (defaults to: nil) —

    map of aliases: key = alias, value = real value

  • default (Object) (defaults to: nil) —

    default value

Returns:

  • value, list or nil



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# File 'lib/aspera/cli/manager.rb', line 183

def get_next_argument(descr, expected: :single, mandatory: true, type: nil, aliases: nil, default: nil)
  Aspera.assert(%i[single multiple].include?(expected) || (expected.is_a?(Array) && expected.all?(Symbol))) do
    'expected must be single, multiple, or array of symbol'
  end
  Aspera.assert(type.nil? || type.is_a?(Class) || (type.is_a?(Array) && type.all?(Class))){'type must be Class or Array of Class'}
  Aspera.assert(aliases.nil? || (aliases.is_a?(Hash) && aliases.keys.all?(Symbol) && aliases.values.all?(Symbol))){'aliases must be Hash'}
  allowed_types = type
  unless allowed_types.nil?
    allowed_types = [allowed_types] unless allowed_types.is_a?(Array)
    descr = "#{descr} (#{allowed_types.join(', ')})"
  end
  result =
    if !@unprocessed_cmd_line_arguments.empty?
      # there are values
      case expected
      when :single
        ExtendedValue.instance.evaluate(@unprocessed_cmd_line_arguments.shift)
      when :multiple
        value = @unprocessed_cmd_line_arguments.shift(@unprocessed_cmd_line_arguments.length).map{|v|ExtendedValue.instance.evaluate(v)}
        # if expecting list and only one arg of type array : it is the list
        if value.length.eql?(1) && value.first.is_a?(Array)
          value = value.first
        end
        value
      when Array
        allowed_values = [].concat(expected)
        allowed_values.concat(aliases.keys) unless aliases.nil?
        self.class.get_from_list(@unprocessed_cmd_line_arguments.shift, descr, allowed_values)
      else Aspera.error_unexpected_value(expected)
      end
    elsif !default.nil? then default
      # no value provided, either get value interactively, or exception
    elsif mandatory then get_interactive(:argument, descr, expected: expected)
    end
  if result.is_a?(String) && allowed_types.eql?(TYPE_INTEGER)
    int_result = Integer(result, exception: false)
    raise Cli::BadArgument, "Invalid integer: #{result}" if int_result.nil?
    result = int_result
  end
  Log.log.debug{"#{descr}=#{result}"}
  result = aliases[result] if aliases&.key?(result)
  self.class.validate_type(:argument, descr, result, allowed_types) unless result.nil? && !mandatory
  return result
end

#get_next_command(command_list, aliases: nil) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 228

def get_next_command(command_list, aliases: nil); return get_next_argument('command', expected: command_list, aliases: aliases); end

#get_option(option_symbol, mandatory: false, default: nil) ⇒ Object

Get an option value by name either return value or calls handler, can return nil ask interactively if requested/required

Parameters:

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

    if true, raise error if option not set



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# File 'lib/aspera/cli/manager.rb', line 234

def get_option(option_symbol, mandatory: false, default: nil)
  attributes = @declared_options[option_symbol]
  Aspera.assert(attributes){"option not declared: #{option_symbol}"}
  result = nil
  case attributes[:read_write]
  when :accessor
    result = attributes[:accessor].value
  when :value
    result = attributes[:value]
  else
    raise 'unknown type'
  end
  Log.log.debug{"(#{attributes[:read_write]}) get #{option_symbol}=#{result}"}
  result = default if result.nil?
  # do not fail for manual generation if option mandatory but not set
  result = '' if result.nil? && mandatory && !@fail_on_missing_mandatory
  # Log.log.debug{"interactive=#{@ask_missing_mandatory}"}
  if result.nil?
    if !@ask_missing_mandatory
      raise Cli::BadArgument, "Missing mandatory option: #{option_symbol}" if mandatory
    elsif @ask_missing_optional || mandatory
      # ask_missing_mandatory
      expected = :single
      # print "please enter: #{option_symbol.to_s}"
      if @declared_options.key?(option_symbol) && attributes.key?(:values)
        expected = attributes[:values]
      end
      result = get_interactive(:option, option_symbol.to_s, expected: expected)
      set_option(option_symbol, result, 'interactive')
    end
  end
  self.class.validate_type(:option, option_symbol, result, attributes[:types]) unless result.nil? && !mandatory
  return result
end

#get_options_table(remove_from_remaining: true) ⇒ Object

get all original options on command line used to generate a config in config file



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# File 'lib/aspera/cli/manager.rb', line 392

def get_options_table(remove_from_remaining: true)
  result = {}
  @initial_cli_options.each do |option_value|
    case option_value
    when /^--([^=]+)$/
      # ignore
    when /^--([^=]+)=(.*)$/
      name = Regexp.last_match(1)
      value = Regexp.last_match(2)
      name.gsub!(OPTION_SEP_LINE, OPTION_SEP_SYMBOL)
      value = ExtendedValue.instance.evaluate(value)
      Log.log.debug{"option #{name}=#{value}"}
      result[name] = value
      @unprocessed_cmd_line_options.delete(option_value) if remove_from_remaining
    else
      raise Cli::BadArgument, "wrong option format: #{option_value}"
    end
  end
  return result
end

#known_options(only_defined: false) ⇒ Hash

Returns options as taken from config file and command line just before command execution.

Parameters:

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

    if true, only return options that were defined

Returns:

  • (Hash) —

    options as taken from config file and command line just before command execution



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# File 'lib/aspera/cli/manager.rb', line 415

def known_options(only_defined: false)
  result = {}
  @declared_options.each_key do |option_symbol|
    v = get_option(option_symbol)
    result[option_symbol] = v unless only_defined && v.nil?
  end
  return result
end

#parse_command_line(argv) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 149

def parse_command_line(argv)
  @parser.separator('')
  @parser.separator('OPTIONS: global')
  declare(:interactive, 'Use interactive input of missing params', values: :bool, handler: {o: self, m: :ask_missing_mandatory})
  declare(:ask_options, 'Ask even optional options', values: :bool, handler: {o: self, m: :ask_missing_optional})
  parse_options!
  process_options = true
  until argv.empty?
    value = argv.shift
    if process_options && value.start_with?('-')
      if value.eql?('--')
        process_options = false
      else
        @unprocessed_cmd_line_options.push(value)
      end
    else
      @unprocessed_cmd_line_arguments.push(value)
    end
  end
  @initial_cli_options = @unprocessed_cmd_line_options.dup
  Log.log.debug{"add_cmd_line_options:commands/arguments=#{@unprocessed_cmd_line_arguments},options=#{@unprocessed_cmd_line_options}".red}
end

#parse_options! ⇒ Object

removes already known options from the list



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# File 'lib/aspera/cli/manager.rb', line 425

def parse_options!
  Log.log.debug('parse_options!'.red)
  # first conf file, then env var
  apply_options_preset(@unprocessed_defaults, 'file')
  apply_options_preset(@unprocessed_env, 'env')
  # command line override
  unknown_options = []
  begin
    # remove known options one by one, exception if unknown
    Log.log.debug('before parse'.red)
    @parser.parse!(@unprocessed_cmd_line_options)
    Log.log.debug('After parse'.red)
  rescue OptionParser::InvalidOption => e
    Log.log.debug{"InvalidOption #{e}".red}
    # save for later processing
    unknown_options.push(e.args.first)
    retry
  end
  Log.log.debug{"remains: #{unknown_options}"}
  # set unprocessed options for next time
  @unprocessed_cmd_line_options = unknown_options
end

#prompt_user_input(prompt, sensitive) ⇒ Object 



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# File 'lib/aspera/cli/manager.rb', line 448

def prompt_user_input(prompt, sensitive)
  return $stdin.getpass("#{prompt}> ") if sensitive
  print("#{prompt}> ")
  line = $stdin.gets
  raise 'Unexpected end of standard input' if line.nil?
  return line.chomp
end

#prompt_user_input_in_list(prompt, sym_list) ⇒ Symbol

prompt user for input in a list of symbols

Parameters:

  • prompt (String) —

    prompt to display

  • sym_list (Array) —

    list of symbols to select from

Returns:

  • (Symbol) —

    selected symbol



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# File 'lib/aspera/cli/manager.rb', line 460

def prompt_user_input_in_list(prompt, sym_list)
  loop do
    input = prompt_user_input(prompt, false).to_sym
    if sym_list.any?{|a|a.eql?(input)}
      return input
    else
      $stderr.puts("No such #{prompt}: #{input}, select one of: #{sym_list.join(', ')}")
    end
  end
end

#set_option(option_symbol, value, where = 'code override') ⇒ Object

set an option value by name, either store value or call handler

Raises:



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# File 'lib/aspera/cli/manager.rb', line 270

def set_option(option_symbol, value, where='code override')
  raise Cli::BadArgument, "Unknown option: #{option_symbol}" unless @declared_options.key?(option_symbol)
  attributes = @declared_options[option_symbol]
  Log.log.warn("#{option_symbol}: Option is deprecated: #{attributes[:deprecation]}") if attributes[:deprecation]
  value = ExtendedValue.instance.evaluate(value)
  value = Manager.enum_to_bool(value) if attributes[:values].eql?(BOOLEAN_VALUES)
  Log.log.debug{"(#{attributes[:read_write]}/#{where}) set #{option_symbol}=#{value}"}
  self.class.validate_type(:option, option_symbol, value, attributes[:types])
  case attributes[:read_write]
  when :accessor
    attributes[:accessor].value = value
  when :value
    attributes[:value] = value
  else # nil or other
    raise 'error'
  end
end