Method: Net::LDAP::Filter#to_ber

Defined in:

lib/net/ldap/filter.rb

#to_ber ⇒ Object

– to_ber Filter ::=

CHOICE {
    and            [0] SET OF Filter,
    or             [1] SET OF Filter,
    not            [2] Filter,
    equalityMatch  [3] AttributeValueAssertion,
    substrings     [4] SubstringFilter,
    greaterOrEqual [5] AttributeValueAssertion,
    lessOrEqual    [6] AttributeValueAssertion,
    present        [7] AttributeType,
    approxMatch    [8] AttributeValueAssertion
}

SubstringFilter

SEQUENCE {
    type               AttributeType,
    SEQUENCE OF CHOICE {
        initial        [0] LDAPString,
        any            [1] LDAPString,
        final          [2] LDAPString
    }
}

Parsing substrings is a little tricky. We use the split method to break a string into substrings delimited by the * (star) character. But we also need to know whether there is a star at the head and tail of the string. A Ruby particularity comes into play here: if you split on * and the first character of the string is a star, then split will return an array whose first element is an empty string. But if the last character of the string is star, then split will return an array that does not add an empty string at the end. So we have to deal with all that specifically.

# File 'lib/net/ldap/filter.rb', line 182

def to_ber
  case @op
  when :eq
    if @right == "*"          # present
      @left.to_s.to_ber_contextspecific 7
    elsif @right =~ /[\*]/    #substring
      ary = @right.split( /[\*]+/ )
      final_star = @right =~ /[\*]$/
      initial_star = ary.first == "" and ary.shift

      seq = []
      unless initial_star
        seq << ary.shift.to_ber_contextspecific(0)
      end
      n_any_strings = ary.length - (final_star ? 0 : 1)
      #p n_any_strings
      n_any_strings.times {
        seq << ary.shift.to_ber_contextspecific(1)
      }
      unless final_star
        seq << ary.shift.to_ber_contextspecific(2)
      end
      [@left.to_s.to_ber, seq.to_ber].to_ber_contextspecific 4
    else                      #equality
      [@left.to_s.to_ber, @right.to_ber].to_ber_contextspecific 3
    end
  when :ge
    [@left.to_s.to_ber, @right.to_ber].to_ber_contextspecific 5
  when :le
    [@left.to_s.to_ber, @right.to_ber].to_ber_contextspecific 6
  when :and
    ary = [@left.coalesce(:and), @right.coalesce(:and)].flatten
    ary.map {|a| a.to_ber}.to_ber_contextspecific( 0 )
  when :or
    ary = [@left.coalesce(:or), @right.coalesce(:or)].flatten
    ary.map {|a| a.to_ber}.to_ber_contextspecific( 1 )
  when :not
      [@left.to_ber].to_ber_contextspecific 2
  else
    # ERROR, we'll return objectclass=* to keep things from blowing up,
    # but that ain't a good answer and we need to kick out an error of some kind.
    raise "unimplemented search filter"
  end
end