Class: Grok::Discovery

Inherits:
Object
  • Object
show all
Defined in:
lib/grok/pure/discovery.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(grok) ⇒ Discovery

Returns a new instance of Discovery.



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# File 'lib/grok/pure/discovery.rb', line 8

def initialize(grok)
  @grok = grok
  @logger = Cabin::Channel.new
  @logger.subscribe(Logger.new(STDOUT))
  @logger.level = :warn
end

Instance Attribute Details

#logger ⇒ Object

Returns the value of attribute logger.



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# File 'lib/grok/pure/discovery.rb', line 6

def logger
  @logger
end

Instance Method Details

#discover(text) ⇒ Object

def initialize



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# File 'lib/grok/pure/discovery.rb', line 15

def discover(text)
  text = text.clone
  # TODO(sissel): Sort patterns by complexity, most complex first.
  #   - For each pattern, compile it in a grok by itself.
  #   - Make a dictionary of { "name" => Grok } for each pattern
  #   - Sort groks by complexity of the Grok#expanded_pattern
  groks = {}
  @grok.patterns.each do |name, expression| 
    grok = Grok.new
    # Copy in the same grok patterns from the parent
    grok.patterns.merge!(@grok.patterns)
    grok.compile("%{#{name}}")
    groks[name] = grok
  end

  patterns = groks.sort { |a, b| compare(a, b) }

  done = false
  while !done
    done = true # will reset this if we are not done later.
    patterns.each do |name, grok|
      # Skip patterns that lack complexity (SPACE, NOTSPACE, DATA, etc)
      next if complexity(grok.expanded_pattern) < 20
      m = grok.match(text)
      # Skip non-matches
      next unless m 
      part = text[m.start ... m.end]
      # Only include things that have word boundaries (not just words)
      next if part !~ /.\b./
      # Skip over parts that appear to include %{pattern} already
      next if part =~ /%{[^}+]}/
      acting = true
      text[m.start ... m.end] = "%{#{name}}"

      # Start the loop over again
      done = false
      break
    end
  end

  return text
end