Class: ActiveLDAP::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/activeldap/base.rb

Overview

Base

Base is the primary class which contains all of the core ActiveLDAP functionality. It is meant to only ever be subclassed by extension classes.

Constant Summary collapse

@@config =

All class-wide variables

nil
@@schema =

Container for current connection settings

nil
@@conn =

LDAP server’s schema

nil
@@reconnect_attempts =

LDAP connection

0

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(val) ⇒ Base

new

Creates a new instance of Base initializing all class and all initialization. Defines local defaults. See examples If multiple values exist for dnattr, the first one put here will be authoritative TODO: Add # support for relative distinguished names val can be a dn attribute value, a full DN, or a LDAP::Entry. The use with a LDAP::Entry is primarily meant for internal use by find and find_all.



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# File 'lib/activeldap/base.rb', line 542

def initialize(val)
  @exists = false
  # Try a default connection if none made explicitly
  if Base.connection.nil? and @@reconnect_attempts < @@config[:retries]
    # Use @@config if it has been prepopulated and the conn is down.
    if @@config
      ActiveLDAP::Base.reconnect
    else
      ActiveLDAP::Base.connect
    end
  elsif Base.connection.nil?
    @@logger.error('Attempted to initialize a new object with no connection')
    raise ConnectionError, 'Number of reconnect attempts exceeded.'
  end
  if val.class == LDAP::Entry
    # Call import, which is basically initialize
    # without accessing LDAP.
    @@logger.debug "initialize: val is a LDAP::Entry - running import."
    import(val)
    return
  end
  if val.class != String
    raise TypeError, "Object key must be a String"
  end

  @data = {} # where the r/w entry data is stored
  @ldap_data = {} # original ldap entry data
  @attr_methods = {} # list of valid method calls for attributes used for dereferencing
  @last_oc = false # for use in other methods for "caching"
  if dnattr().empty?
    raise RuntimeError, "dnattr() not set for this class."
  end

  # Break val apart if it is a dn
  if val.match(/^#{dnattr()}=([^,=]+),#{base()}$/i)
    val = $1
  elsif val.match(/[=,]/)
    @@logger.info "initialize: Changing val from '#{val}' to '' because it doesn't match the DN."
    val = ''
  end

  # Do a search - if it exists, pull all data and parse schema, if not, just set the hierarchical data
  if val.class != String or val.empty?
    raise TypeError, 'a dn attribute String must be supplied ' +
      'on initialization'
  else
    # Create what should be the authoritative DN
    @dn = "#{dnattr()}=#{val},#{base()}"

    # Search for the existing entry
    begin
      # Get some attributes
      Base.connection.search(base(), @@config[:ldap_scope], "(#{dnattr()}=#{val})")  do |m|
        @exists = true
        # Save DN
        @dn = m.dn
        # Load up data into tmp
        @@logger.debug("loading entry: #{@dn}")
        m.attrs.each do |attr|
          # Load with subtypes just like @data
          @@logger.debug("calling make_subtypes for m.vals(attr).dup")
          safe_attr, value = make_subtypes(attr, m.vals(attr).dup)
          @@logger.debug("finished make_subtypes for #{attr}")
          # Add subtype to any existing values
          if @ldap_data.has_key? safe_attr
            value.each do |v|
              @ldap_data[safe_attr].push(v)
            end
          else
            @ldap_data[safe_attr] = value
          end
        end
      end
    rescue RuntimeError => detail
      #TODO# Check for 'No message' when retrying
      # The connection may have gone stale. Let's reconnect and retry. 
      retry if Base.reconnect()

      # Do nothing on failure
      @@logger.error('new: unable to search for entry')
      raise detail
    rescue LDAP::ResultError
    end
  end

  # Do the actual object setup work.
  if @exists
    # Populate schema data
    send(:apply_objectclass, @ldap_data['objectClass'])

    # Populate real data now that we have the schema with aliases
    @ldap_data.each do |pair|
      real_attr = @attr_methods[pair[0]]
      @@logger.debug("new: #{pair[0].inspect} method maps to #{real_attr}")
      @data[real_attr] = pair[1].dup
      @@logger.debug("new: #{real_attr} set to #{pair[1]}")
    end
  else
    send(:apply_objectclass, required_classes())

    # Setup dn attribute (later rdn too!)
    real_dnattr = @attr_methods[dnattr()]
    @data[real_dnattr] = val
    @@logger.debug("new: setting dnattr: #{real_dnattr} = #{val}")
  end
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(name, *args) ⇒ Object

method_missing

If a given method matches an attribute or an attribute alias then call the appropriate method. TODO: Determine if it would be better to define each allowed method

using class_eval instead of using method_missing.  This would
give tab completion in irb.

Raises:

  • (NoMethodError) 


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# File 'lib/activeldap/base.rb', line 937

def method_missing(name, *args)
  @@logger.debug("stub: called method_missing(#{name.inspect}, #{args.inspect})")

  # dynamically update the available attributes without requiring an
  # explicit call. The cache 'last_oc' saves a lot of cpu time.
  if @data['objectClass'] != @last_oc
    @@logger.debug("method_missing(#{name.inspect}, #{args.inspect}): updating apply_objectclass(#{@data['objectClass'].inspect})")
    send(:apply_objectclass, @data['objectClass'])
  end
  key = name.to_s
  case key
    when /^(\S+)=$/
      real_key = $1
      @@logger.debug("method_missing: attr_methods has_key? #{real_key}")
      if @attr_methods.has_key? real_key
        raise ArgumentError, "wrong number of arguments (#{args.size} for 1)" if args.size != 1
        @@logger.debug("method_missing: calling :attribute_method=(#{real_key}, #{args[0]})")
        return send(:attribute_method=, real_key, args[0])
      end
    else
      @@logger.debug("method_missing: attr_methods has_key? #{key}")
      if @attr_methods.has_key? key
        raise ArgumentError, "wrong number of arguments (#{args.size} for 1)" if args.size > 1
        return attribute_method(key, *args)
      end
  end
  raise NoMethodError, "undefined method `#{key}' for #{self}"
end

Instance Attribute Details

#logger ⇒ Object

Returns the value of attribute logger.



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# File 'lib/activeldap/base.rb', line 106

def logger
  @logger
end

#may ⇒ Object (readonly)

Parsed schema structures



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# File 'lib/activeldap/base.rb', line 105

def may
  @may
end

#must ⇒ Object (readonly)

Parsed schema structures



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# File 'lib/activeldap/base.rb', line 105

def must
  @must
end

Class Method Details

.base ⇒ Object

Make the return value the string that is your LDAP base



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# File 'lib/activeldap/base.rb', line 501

def Base.base
  'dc=example,dc=com'
end

.close ⇒ Object

Base.close This method deletes the LDAP connection object. This does NOT reset any overridden values from a Base.connect call.



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# File 'lib/activeldap/base.rb', line 237

def Base.close
  begin
    @@conn.unbind unless @@conn.nil?
  rescue
    # Doesn't matter.
  end
  @@conn = nil
  # Make sure it is cleaned up
  ObjectSpace.garbage_collect
end

.connect(config = {}) ⇒ Object

Connect and bind to LDAP creating a class variable for use by all ActiveLDAP objects.

config

config must be a hash that may contain any of the following fields: :user, :password_block, :logger, :host, :port, :base, :bind_format, :try_sasl, :allow_anonymous :user specifies the username to bind with. :bind_format specifies the string to substitute the username into on bind. e.g. uid=%s,ou=People,dc=dataspill,dc=org. Overrides @@bind_format. :password_block specifies a Proc object that will yield a String to be used as the password when called. :logger specifies a preconfigured Log4r::Logger to be used for all logging :host sets the LDAP server hostname :port sets the LDAP server port :base overwrites Base.base - this affects EVERYTHING :try_sasl indicates that a SASL bind should be attempted when binding to the server (default: false) :allow_anonymous indicates that a true anonymous bind is allowed when trying to bind to the server (default: true) :retries - indicates the number of attempts to reconnect that will be undertaken when a stale connection occurs. -1 means infinite. :sasl_quiet - if true, sets @sasl_quiet on the Ruby/LDAP connection :method - whether to use :ssl, :tls, or :plain (unencrypted) :retry_wait - seconds to wait before retrying a connection :ldap_scope - dictates how to find objects. ONELEVEL by default to avoid dn_attr collisions across OUs. Think before changing. See lib/configuration.rb for defaults for each option



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# File 'lib/activeldap/base.rb', line 200

def Base.connect(config={})
  # Process config
  # Class options
  ## These will be replace by configuration.rb defaults if defined
  @@config = DEFAULT_CONFIG.dup
  config.keys.each do |key|
    if key == :base
      # Scrub before inserting
      base = config[:base].gsub(/['}{#]/, '')
      Base.class_eval("def Base.base();'#{base}';end")
    else
      @@config[key] = config[key]
    end
  end
  # Assign a easier name for the logger
  @@logger = @@config[:logger] || nil
  # Setup default logger to console
  if @@logger.nil?
    @@logger = Log4r::Logger.new('activeldap')
    @@logger.level = Log4r::OFF
    Log4r::StderrOutputter.new 'console'
    @@logger.add('console')
  end

  # Reset for the new connection
  @@reconnect_attempts = 0

  # Make the connection.
  do_connect()

  # Make irb users happy with a 'true'
  return true
end

.connection ⇒ Object

Return the LDAP connection object currently in use



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# File 'lib/activeldap/base.rb', line 249

def Base.connection
  return @@conn
end

.connection=(conn) ⇒ Object

Set the LDAP connection avoiding Base.connect or multiplexing connections



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# File 'lib/activeldap/base.rb', line 254

def Base.connection=(conn)
  @@conn = conn
end

.create_object(config = {}) ⇒ Object

Driver generator

TODO add type checking This let’s you call this method to create top-level extension object. This is really just a proof of concept and has not truly useful purpose. example: Base.create_object(:class => “user”, :dnattr => “uid”, :classes => [‘top’])

THIS METHOD IS DANGEROUS. INPUT IS NOT SANITIZED.

Raises:

  • (TypeError) 


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# File 'lib/activeldap/base.rb', line 122

def Base.create_object(config={})
  # Just upcase the first letter of the new class name
  str = config[:class]
  class_name = str[0].chr.upcase + str[1..-1]

  attr = config[:dnattr] # "uid"
  prefix = config[:base] # "ou=People"
  # [ 'top', 'posixAccount' ]
  classes_array = config[:classes] || []
  # [ [ :groups, {:class_name => "Group", :foreign_key => "memberUid"}] ]
  belongs_to_array = config[:belongs_to] || []
  # [ [ :members, {:class_name => "User", :foreign_key => "uid", :local_key => "memberUid"}] ]
  has_many_array = config[:has_many] || []

  raise TypeError, ":objectclasses must be an array" unless classes_array.respond_to? :size
  raise TypeError, ":belongs_to must be an array" unless belongs_to_array.respond_to? :size
  raise TypeError, ":has_many must be an array" unless has_many_array.respond_to? :size

  # Build classes array
  classes = '['
  classes_array.map! {|x| x = "'#{x}'"}
  classes << classes_array.join(', ')
  classes << ']'

  # Build belongs_to
  belongs_to = []
  if belongs_to_array.size > 0
    belongs_to_array.each do |bt|
      line = [ "belongs_to :#{bt[0]}" ]
      bt[1].keys.each do |key|
        line << ":#{key} => '#{bt[1][key]}'"
      end
      belongs_to << line.join(', ')
    end
  end

  # Build has_many
  has_many = []
  if has_many_array.size > 0
    has_many_array.each do |hm|
      line = [ "has_many :#{hm[0]}" ]
      hm[1].keys.each do |key|
        line << ":#{key} => '#{hm[1][key]}'"
      end
      has_many << line.join(', ')
    end
  end

  self.class.module_eval <<-"end_eval"
    class ::#{class_name} < ActiveLDAP::Base
      ldap_mapping :dnattr => "#{attr}", :prefix => "#{prefix}", :classes => #{classes}
      #{belongs_to.join("\n")}
      #{has_many.join("\n")}
    end
  end_eval
end

.dnattr ⇒ Object

Base.dnattr

This is a placeholder for the class method that will be overridden on calling ldap_mapping in a subclass. Using a class method allows for clean inheritance from classes that already have a ldap_mapping.



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# File 'lib/activeldap/base.rb', line 511

def Base.dnattr
 ''
end

.reconnect(force = false) ⇒ Object

Attempts to reconnect up to the number of times allowed If forced, try once then fail with ConnectionError if not connected.



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# File 'lib/activeldap/base.rb', line 260

def Base.reconnect(force=false)
  not_connected = true
  while not_connected
    # Just to be clean, unbind if possible
    begin
      @@conn.unbind() if not @@conn.nil? and @@conn.bound?
    rescue
      # Ignore complaints.
    end
    @@conn = nil

    if @@config[:retries] == -1 or force == true
      @@logger.debug('Attempting to reconnect')

      # Reset the attempts if this was forced.
      @@reconnect_attempts = 0 if @@reconnect_attempts != 0
      begin
        do_connect() 
        not_connected = false
      rescue => detail
        @@logger.error("Reconnect to server failed: #{detail.exception}")
        @@logger.error("Reconnect to server failed backtrace: #{detail.backtrace}")
        # Do not loop if forced
        raise ConnectionError, detail.message if force
      end
    elsif @@reconnect_attempts < @@config[:retries]
      @@logger.debug('Attempting to reconnect')
      @@reconnect_attempts += 1
      begin
        do_connect() 
        not_connected = false
        # Reset to 0 if a connection was made. 
        @@reconnect_attempts = 0
      rescue => detail
        @@logger.error("Reconnect to server failed: #{detail.exception}")
        @@logger.error("Reconnect to server failed backtrace: #{detail.backtrace}")
      end
    else
      # Raise a warning
      raise ConnectionError, 'Giving up trying to reconnect to LDAP server.'
    end

    # Sleep before looping
    sleep @@config[:retry_wait]
  end
  return true
end

.required_classes ⇒ Object

This is optionally set to the array of objectClass names that are minimally required for EVERY object on your LDAP server. If you don’t want one, set this to [].



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# File 'lib/activeldap/base.rb', line 525

def Base.required_classes
  []
end

.schema ⇒ Object

Return the schema object



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# File 'lib/activeldap/base.rb', line 309

def Base.schema
  @@schema
end

.search(config = {}) ⇒ Object

search

Wraps Ruby/LDAP connection.search to make it easier to search for specific data without cracking open Base.connection



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# File 'lib/activeldap/base.rb', line 317

def Base.search(config={})
  unless Base.connection
    if @@config
      ActiveLDAP::Base.connect(@@config)
    else
      ActiveLDAP::Base.connect
    end
  end

  config[:filter] = 'objectClass=*' unless config.has_key? :filter
  config[:attrs] = [] unless config.has_key? :attrs
  config[:scope] = LDAP::LDAP_SCOPE_SUBTREE unless config.has_key? :scope
  config[:base] = base() unless config.has_key? :base

  values = []
  config[:attrs] = config[:attrs].to_a # just in case

  begin
    @@conn.search(config[:base], config[:scope], config[:filter], config[:attrs])  do |m|
      res = {}
      res['dn'] = [m.dn.dup] # For consistency with the below
      m.attrs.each do |attr|
        if config[:attrs].member? attr or config[:attrs].empty?
          res[attr] = m.vals(attr).dup
        end
      end
      values.push(res)
    end
  rescue RuntimeError => detail
    #TODO# Check for 'No message' when retrying
    # The connection may have gone stale. Let's reconnect and retry. 
    retry if Base.reconnect()
    # Do nothing on failure
    @@logger.debug "No matches for #{config[:filter]} and attrs #{config[:attrs]}"
  rescue => detail
    if LDAP::err2exception(@@conn.err)[0] == LDAP::ServerDown
      @@logger.debug("Failed to write: #{entry}")
      retry if Base.reconnect()
    end
    raise detail
  end
  return values
end

Instance Method Details

#__methods ⇒ Object

Add available attributes to the methods



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# File 'lib/activeldap/base.rb', line 967

alias_method :__methods, :methods

#attributes ⇒ Object

attributes

Return attribute methods so that a program can determine available attributes dynamically without schema awareness



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# File 'lib/activeldap/base.rb', line 656

def attributes
  @@logger.debug("stub: attributes called")
  send(:apply_objectclass, @data['objectClass']) if @data['objectClass'] != @last_oc
  return @attr_methods.keys
end

#delete ⇒ Object

delete

Delete this entry from LDAP



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# File 'lib/activeldap/base.rb', line 725

def delete
  @@logger.debug("stub: delete called")
  begin
    @@conn.delete(@dn)
    @exists = false
  rescue RuntimeError => detail
    #todo# check for 'no message' when retrying
    # the connection may have gone stale. let's reconnect and retry. 
    retry if Base.reconnect()
    raise DeleteError, "Failed to delete LDAP entry: '#{@dn}'"
  rescue LDAP::ResultError => detail
    if LDAP::err2exception(@@conn.err)[0] == LDAP::ServerDown
      @@logger.debug("Failed to write: #{entry}")
      retry if Base.reconnect()
    end
    raise DeleteError, "Failed to delete LDAP entry: '#{@dn}'"
  end
end

#dn ⇒ Object

dn

Return the authoritative dn



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# File 'lib/activeldap/base.rb', line 673

def dn
  @@logger.debug("stub: dn called")
  return @dn.dup
end

#exists? ⇒ Boolean

exists?

Return whether the entry exists in LDAP or not

Returns:

  • (Boolean) 


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# File 'lib/activeldap/base.rb', line 665

def exists?
  @@logger.debug("stub: exists? called")
  return @exists
end

#methods ⇒ Object 



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# File 'lib/activeldap/base.rb', line 968

def methods
  return __methods + attributes()
end

#validate ⇒ Object

validate

Basic validation:

  • Verify that every ‘MUST’ specified in the schema has a value defined

  • Enforcement of undefined attributes is handled in the objectClass= method

Must call enforce_types() first before enforcement can be guaranteed



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# File 'lib/activeldap/base.rb', line 684

def validate
  @@logger.debug("stub: validate called")
  # Clean up attr values, etc
  send(:enforce_types)

  # Validate objectclass settings
  @data['objectClass'].each do |klass|
    unless klass.class == String
      raise TypeError, "Value in objectClass array is not a String. (#{klass.class}:#{klass.inspect})"
    end
    unless Base.schema.names("objectClasses").member? klass
      raise ObjectClassError, "objectClass '#{klass}' unknown to LDAP server."
    end
  end

  # make sure this doesn't drop any of the required objectclasses
  required_classes().each do |oc|
    unless @data['objectClass'].member? oc.to_s
      raise ObjectClassError, "'#{oc}' must be a defined objectClass for class '#{self.class}' as set in the ldap_mapping"
    end
  end

  # Make sure all MUST attributes have a value
  @data['objectClass'].each do |objc|
    @must.each do |req_attr|
      deref = @attr_methods[req_attr]
      # Set default if it wasn't yet set.
      @data[deref] = [] if @data[deref].nil?
      # Check for missing requirements.
      if @data[deref].empty?
        raise AttributeEmpty,
          "objectClass '#{objc}' requires attribute '#{Base.schema.attribute_aliases(req_attr).join(', ')}'"
      end
    end
  end
  @@logger.debug("stub: validate finished")
end

#write ⇒ Object

write

Write and validate this object into LDAP either adding or replacing attributes TODO: Binary data support TODO: Relative DN support



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# File 'lib/activeldap/base.rb', line 751

def write
  @@logger.debug("stub: write called")
  # Validate against the objectClass requirements
  validate

  # Put all changes into one change entry to ensure
  # automatic rollback upon failure.
  entry = []


  # Expand subtypes to real ldap_data entries
  # We can't reuse @ldap_data because an exception would leave
  # an object in an unknown state
  @@logger.debug("#write: dup'ing @ldap_data")
  ldap_data = Marshal.load(Marshal.dump(@ldap_data))
  @@logger.debug("#write: dup finished @ldap_data")
  @@logger.debug("#write: expanding subtypes in @ldap_data")
  ldap_data.keys.each do |key|
    ldap_data[key].each do |value|
      if value.class == Hash
        suffix, real_value = extract_subtypes(value)
        if ldap_data.has_key? key + suffix
          ldap_data[key + suffix].push(real_value)
        else
          ldap_data[key + suffix] = real_value
        end
        ldap_data[key].delete(value)
      end
    end
  end
  @@logger.debug("#write: subtypes expanded for @ldap_data")

  # Expand subtypes to real data entries, but leave @data alone
  @@logger.debug("#write: dup'ing @data")
  data = Marshal.load(Marshal.dump(@data))
  @@logger.debug("#write: finished dup'ing @data")
  @@logger.debug("#write: expanding subtypes for @data")
  data.keys.each do |key|
    data[key].each do |value|
      if value.class == Hash
        suffix, real_value = extract_subtypes(value)
        if data.has_key? key + suffix
          data[key + suffix].push(real_value)
        else
          data[key + suffix] = real_value
        end
        data[key].delete(value)
      end
    end
  end
  @@logger.debug("#write: subtypes expanded for @data")


  if @exists
    # Cycle through all attrs to determine action
    action = {}

    replaceable = []
    # Now that all the subtypes will be treated as unique attributes
    # we can see what's changed and add anything that is brand-spankin'
    # new.
    @@logger.debug("#write: traversing ldap_data determining replaces and deletes")
    ldap_data.each do |pair|
      suffix = ''
      binary = 0

      name, *suffix_a = pair[0].split(/;/)
      suffix = ';'+ suffix_a.join(';') if suffix_a.size > 0
      name = @attr_methods[name]
      name = pair[0].split(/;/)[0] if name.nil? # for objectClass, or removed vals
      value = data[name+suffix]
      # If it doesn't exist, don't freak out.
      value = [] if value.nil?

      # Detect subtypes and account for them
      binary = LDAP::LDAP_MOD_BVALUES if Base.schema.binary? name

      replaceable.push(name+suffix)
      if pair[1] != value
        # Create mod entries
        if not value.empty?
          # Ditched delete then replace because attribs with no equality match rules
          # will fails
          @@logger.debug("updating attribute of existing entry:  #{name+suffix}: #{value.inspect}")
          entry.push(LDAP.mod(LDAP::LDAP_MOD_REPLACE|binary, name + suffix, value))
        else
          # Since some types do not have equality matching rules, delete doesn't work
          # Replacing with nothing is equivalent.
          @@logger.debug("removing attribute from existing entry:  #{name+suffix}")
          entry.push(LDAP.mod(LDAP::LDAP_MOD_REPLACE|binary, name + suffix, []))
        end
      end
    end
    @@logger.debug("#write: finished traversing ldap_data")
    @@logger.debug("#write: traversing data determining adds")
    data.each do |pair|
      suffix = ''
      binary = 0

      name, *suffix_a = pair[0].split(/;/)
      suffix = ';' + suffix_a.join(';') if suffix_a.size > 0
      name = @attr_methods[name]
      name = pair[0].split(/;/)[0] if name.nil? # for obj class or removed vals
      value = pair[1]
      # Make sure to change this to an Array if there was mistake earlier.
      value = [] if value.nil?

      if not replaceable.member? name+suffix
        # Detect subtypes and account for them
        binary = LDAP::LDAP_MOD_BVALUES if Base.schema.binary? name
        @@logger.debug("adding attribute to existing entry:  #{name+suffix}: #{value.inspect}")
        # REPLACE will function like ADD, but doesn't hit EQUALITY problems
        # TODO: Added equality(attr) to Schema2
        entry.push(LDAP.mod(LDAP::LDAP_MOD_REPLACE|binary, name + suffix, value)) unless value.empty?
      end
    end
    @@logger.debug("#write: traversing data complete")
    begin
      @@logger.debug("#write: modifying #{@dn}")
      @@conn.modify(@dn, entry)
      @@logger.debug("#write: modify successful")
    rescue RuntimeError => detail
      #todo# check for SERVER_DOWN
      # the connection may have gone stale. let's reconnect and retry. 
      retry if Base.reconnect()
      raise WriteError, "Could not update LDAP entry: #{detail}"
    rescue => detail
      @@logger.debug(LDAP::err2exception(@@conn.err).inspect)
      if LDAP::err2exception(@@conn.err)[0] == LDAP::ServerDown
        @@logger.debug("Failed to write: #{entry}")
        retry if Base.reconnect()
      end
      @@logger.debug("Failed to write: #{entry}")
      raise WriteError, "Could not update LDAP entry: #{detail}"
    end
  else # add everything!
    @@logger.debug("#write: adding all attribute value pairs")
    @@logger.debug("#write: adding #{@attr_methods[dnattr()].inspect} = #{data[@attr_methods[dnattr()]].inspect}")
    entry.push(LDAP.mod(LDAP::LDAP_MOD_ADD, @attr_methods[dnattr()], 
      data[@attr_methods[dnattr()]]))
    @@logger.debug("#write: adding objectClass = #{data[@attr_methods['objectClass']].inspect}")
    entry.push(LDAP.mod(LDAP::LDAP_MOD_ADD, 'objectClass', 
      data[@attr_methods['objectClass']]))
    data.each do |pair|
      if pair[1].size > 0  and pair[0] != 'objectClass' and pair[0] != @attr_methods[dnattr()]
        # Detect subtypes and account for them
        if Base.schema.binary? pair[0].split(/;/)[0]
          binary = LDAP::LDAP_MOD_BVALUES 
        else
          binary = 0
        end
        @@logger.debug("adding attribute to new entry:  #{pair[0].inspect}: #{pair[1].inspect}")
        entry.push(LDAP.mod(LDAP::LDAP_MOD_ADD|binary, pair[0], pair[1]))
      end
    end
    begin
      @@logger.debug("#write: adding #{@dn}")
      @@conn.add(@dn, entry)
      @@logger.debug("#write: add successful")
      @exists = true
    rescue RuntimeError => detail
      # The connection may have gone stale. Let's reconnect and retry. 
      retry if Base.reconnect()
      raise WriteError, "Could not add LDAP entry[#{Base.connection.err2string(Base.connection.err)}]: #{detail}"
    rescue LDAP::ResultError => detail
      if LDAP::err2exception(@@conn.err)[0] == LDAP::ServerDown
        @@logger.debug("Failed to write: #{entry}")
        retry if Base.reconnect()
      end
      raise WriteError, "Could not add LDAP entry[#{Base.connection.err2string(Base.connection.err)}]: #{detail}"
    end
  end
  @@logger.debug("#write: resetting @ldap_data to a dup of @data")
  @ldap_data = Marshal.load(Marshal.dump(@data))
  @@logger.debug("#write: @ldap_data reset complete")
  @@logger.debug("stub: write exitted")
end