Class: Nexpose::Service

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

Overview

This class represents each of the /NexposeReport/nodes/node/endpoints/endpoint/services/service elements in the Nexpose Full XML document.

It provides a convenient way to access the information scattered all over the XML in attributes and nested tags.

Instead of providing separate methods for each supported property we rely on Ruby’s #method_missing to do most of the work.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(xml_node, endpoint: nil) ⇒ Service

Accepts an XML node from Nokogiri::XML.

endpoint - If the Service is instantiated from the Endpoint class (e.g. from <endpoint><services>…) , it will have access to the parent data.



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# File 'lib/nexpose/service.rb', line 17

def initialize(xml_node, endpoint: nil)
  @xml = xml_node
  @endpoint = endpoint
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method, *args) ⇒ Object

This method is invoked by Ruby when a method that is not defined in this instance is called.

In our case we inspect the @method@ parameter and try to find the attribute, simple descendent or collection that it maps to in the XML tree.



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# File 'lib/nexpose/service.rb', line 60

def method_missing(method, *args)
  # We could remove this check and return nil for any non-recognized tag.
  # The problem would be that it would make tricky to debug problems with
  # typos. For instance: <>.potr would return nil instead of raising an
  # exception
  unless supported_tags.include?(method)
    super
    return
  end

  # First we try the attributes. In Ruby we use snake_case, but in XML
  # CamelCase is used for some attributes
  translations_table = {}

  method_name = translations_table.fetch(method, method.to_s)
  return xml.attributes[method_name].value if xml.attributes.key?(method_name)

  # Finally the enumerations: references, tags
  if ['fingerprints', 'configurations'].include?(method_name)
    xpath_selector = {
      'fingerprints' => './fingerprints/fingerprint',
      'configurations' => './configuration/config'
    }[method_name]

    xml.xpath(xpath_selector).collect do |xml_item|
      { text: xml_item.text }.merge(
        Hash[
          xml_item.attributes.collect do |name, xml_attribute|
            [name.sub(/-/, '_').to_sym, xml_attribute.value]
          end
        ]
      )
    end
  else
    # nothing found, the tag is valid but not present in this ReportItem
    return nil
  end
end

Instance Attribute Details

#endpoint ⇒ Object

Returns the value of attribute endpoint.



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# File 'lib/nexpose/service.rb', line 11

def endpoint
  @endpoint
end

#xml ⇒ Object

Returns the value of attribute xml.



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# File 'lib/nexpose/service.rb', line 11

def xml
  @xml
end

Instance Method Details

#respond_to?(method, include_private = false) ⇒ Boolean

This allows external callers (and specs) to check for implemented properties

Returns:

  • (Boolean) 


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# File 'lib/nexpose/service.rb', line 49

def respond_to?(method, include_private = false)
  return true if supported_tags.include?(method.to_sym)
  super
end

#supported_tags ⇒ Object

List of supported tags. They can be attributes, simple descendans or collections (e.g. <references/>, <tags/>)



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# File 'lib/nexpose/service.rb', line 24

def supported_tags
  [
    # attributes
    :name,

    # simple tags

    # multiple tags
    :fingerprints, :configurations, :tests
  ]
end

#tests(*args) ⇒ Object

Convert each ./test/test entry into a simple hash



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# File 'lib/nexpose/service.rb', line 37

def tests(*args)
  xml.xpath('./tests/test').map do |xml_test|
    # Inject evidence with data from the node
    xml_test['port'] = endpoint[:port]
    xml_test['protocol'] = endpoint[:protocol]

    Nexpose::Test.new(xml_test)
  end
end