Class: Coppertone::Modifier::Exp

Inherits:
Base show all
Defined in:
lib/coppertone/modifier/exp.rb

Overview

Exp modifier - specifying a message to be returned in case of failure

Constant Summary collapse

ASCII_REGEXP = 
/\A[[:ascii:]]*\z/

Constants inherited from Coppertone::Modifier

MODIFIER_REGEXP

Instance Attribute Summary

Attributes inherited from Base

#domain_spec

Attributes inherited from Coppertone::Modifier

#arguments

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Base

#==, #context_dependent?, #includes_ptr?, #initialize, #target_name_from_domain_spec

Methods inherited from Coppertone::Modifier

build, build_unknown, class_builder, #initialize, #label, matching_term, register, #to_s

Constructor Details

This class inherits a constructor from Coppertone::Modifier::Base

Class Method Details

.create(attributes) ⇒ Object 



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# File 'lib/coppertone/modifier/exp.rb', line 7

def self.create(attributes)
  new(attributes)
end

.label ⇒ Object 



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# File 'lib/coppertone/modifier/exp.rb', line 33

def self.label
  'exp'
end

Instance Method Details

#evaluate(macro_context, request_context) ⇒ Object 



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# File 'lib/coppertone/modifier/exp.rb', line 12

def evaluate(macro_context, request_context)
  target_name =
    target_name_from_domain_spec(macro_context, request_context)
  return nil unless target_name
  macro_string = lookup_macro_string(target_name, request_context)
  return nil unless macro_string
  expanded = macro_string.expand(macro_context, request_context)
  return nil unless ASCII_REGEXP.match(expanded)
  expanded
rescue DNSAdapter::Error
  nil
end

#lookup_macro_string(target_name, request_context) ⇒ Object 



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# File 'lib/coppertone/modifier/exp.rb', line 25

def lookup_macro_string(target_name, request_context)
  records =
    request_context.dns_client.fetch_txt_records(target_name)
  return nil if records.empty?
  return nil if records.size > 1
  MacroString.new(records.first[:text])
end