Contents

module LogfmtMarshalling
  class Marshaller
    def marshal(hash)
      hash.inject([]) do |acc, (key, value)|
        case value
          when TrueClass then acc << marshal_key(key)
          else                acc << [marshal_key(key), marshal_value(value)].join('=')
        end
        acc
      end.join ' '
    end

    private

    def marshal_key(key)
      key.to_s
    end

    def marshal_value(value)
      case value
        when String then marshal_string_value value
        else             value.to_s
      end
    end

    def marshal_string_value(value)
      handle_special_case(value) || wrap_in_quotes(escapes_double_quotes(value))
    end

    def escapes_double_quotes(value)
      value.gsub '[^\]"', '\"'
    end

    def wrap_in_quotes(value)
      if value.match(/\\|\s/)
        %{"#{value}"}
      else
        value
      end
    end

    def handle_special_case(value)
      case value
        when '' then '""'
        when 'false' then '"false"'
        when 'true' then '"true"'
        when /\d/ then handle_string_with_number(value)
      end
    end

    def handle_string_with_number(value)
      Kernel.Float value
      %{"#{value}"}
    rescue ArgumentError
      # Not a number. Will be handled later.
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
logfmt_marshalling-0.0.2	lib/logfmt_marshalling/marshaller.rb
logfmt_marshalling-0.0.1	lib/logfmt_marshalling/marshaller.rb