Net::LDAP::Examples - PERL LDAP by Example

The following examples are of course PERL code, found to work with the Net::LDAP modules.

The intent of this document is to give the reader a cut and paste jump start to getting an LDAP application working.

Below you will find snippets of code that should work as-is with only a small amount of work to correct any variable assignments and LDAP specifics, e.g. Distinguished Name Syntax, related to the user's own implementation.

The Standard Operating Proceedure that is followed here is:

1 Package - use Net::LDAP

2 Initialization - new

3 Binding - bind

4 Operation - add modify moddn search

4.1 Processing - displaying data from a search

5 Error - displaying error information

6 Unbinding - unbind

Look to each of these for a snippet of code to meet your needs.

What is not covered in these examples at this time:

abandon and compare methods

callback subroutines

 use Net::LDAP;

 $ldap = Net::LDAP->new ( "yourLDAPhost.yourCompany.com" ) or die "$@";

 $mesg = $ldap->bind ( version => 3 );          # use for searches

 $mesg = $ldap->bind ( "$userToAuthenticate",           
                       password => "$passwd",
                       version => 3 );          # use for changes/edits

 # see your LDAP administrator for information concerning the
 # user authentication setup at your site.

 sub LDAPsearch
 {
   my ($ldap,$searchString,$attrs,$base) = @_;

   # if they don't pass a base... set it for them

   if (!$base ) { $base = "o=mycompany, c=mycountry"; }

   # if they don't pass an array of attributes...
   # set up something for them

   if (!$attrs ) { $attrs = [ 'cn','mail' ]; }

   my $result = $ldap->search ( base    => "$base",
                                scope   => "sub",
                                filter  => "$searchString",
                                attrs   =>  $attrs
                              );

}

 my @Attrs = ( );               # request all available attributes
                                # to be returned.

 my $result = LDAPsearch ( $ldap, "sn=*", \@Attrs );

 #------------
 #
 # Accessing the data as if in a structure
 #  i.e. Using the "as_struct"  method
 #

 my $href = $result->as_struct;

 # get an array of the DN names

 my @arrayOfDNs  = keys %$href;        # use DN hashes

 # process each DN using it as a key

 foreach ( @arrayOfDNs ) {
   print $_, "\n";
   my $valref = $$href{$_};

   # get an array of the attribute names
   # passed for this one DN.
   my @arrayOfAttrs = sort keys %$valref; #use Attr hashes

   my $attrName;        
   foreach $attrName (@arrayOfAttrs) {

     # skip any binary data: yuck!
     next if ( $attrName =~ /;binary$/ );

     # get the attribute value (pointer) using the
     # attribute name as the hash
     my $attrVal =  @$valref{$attrName};
     print "\t $attrName: @$attrVal \n";
   }
   print "#-------------------------------\n";
   # End of that DN
 }
 #
 #  end of as_struct method
 #
 #--------

 #------------
 #
 # handle each of the results independently
 # ... i.e. using the walk through method
 #
 my @entries = $result->entries;

 my $entr;
 foreach $entr ( @entries ) {
   print "DN: ", $entr->dn, "\n";

   my $attr;
   foreach $attr ( sort $entr->attributes ) {
     # skip binary we can't handle
     next if ( $attr =~ /;binary$/ );
     print "  $attr : ", $entr->get_value ( $attr ) ,"\n";
   }

   print "#-------------------------------\n";
 }

 #
 # end of walk through method
 #------------

 #
 #   Modify
 #
 #  for each of the modifies below you'll need to supply
 #  a full DN (Distinguished Name) for the $dn variable.
 #   example:
 #    cn=Jo User,ou=person,o=mycompany,c=mycountry
 #
 #   I would recommend doing a search (listed above)
 #   then use the dn returned to populate the $dn variable.

 #
 #  Do we only have one result returned from the search?

 if ( $result->count != 1 ) { exit; }  # Nope.. exit

 my $dn = $entries[0]->dn;         # yes.. get the DN

 #######################################
 #
 #   MODIFY using a HASH
 #

 my %ReplaceHash = ( keyword => "x", proxy => "x" );

 my $result = LDAPmodifyUsingHash ( $ldap, $dn, \%ReplaceHash );

 sub LDAPmodifyUsingHash
 {
   my ($ldap, $dn, $whatToChange ) = @_;
   my $result = $ldap->modify ( $dn,
                                replace => { %$whatToChange }
                              );
   return $result;
 }

 #######################################
 #
 #   MODIFY using a ARRAY List
 #

 my @ReplaceArrayList = [ 'keyword', "xxxxxxxxxx",
                          'proxy' , "yyyyyyyyyy"   ];

 my $result = LDAPmodifyUsingArrayList ( $ldap, $dn, \@ReplaceArrayList );

 sub LDAPmodifyUsingArrayList
 {
   my ($ldap, $dn, $whatToChange ) = @_;
   my $result = $ldap->modify ( $dn,
                                changes => [
                                  replace => @$whatToChange
                                ]
                              );
   return $result;
 }

 #######################################
 #
 #   MODIFY using a ARRAY
 #

 my @ReplaceArray = ( 'keyword', "xxxxxxxxxx" ,
                      'proxy' , "yyyyyyyyyy"   );

 my $result = LDAPmodifyUsingArray ( $ldap, $dn, \@ReplaceArray );

 sub LDAPmodifyUsingArray
 {
   my ($ldap, $dn, $whatToChange ) = @_;
   my $result = $ldap->modify ( $dn,
                                changes => [
                                  replace => [ @$whatToChange ]
                                ]
                              );
   return $result;
 }

 #######################################
 #
 #   MODIFY an existing record using 'Changes'
 #    (or combination of add/delete/replace)
 #

 my @whatToChange;
 my @ReplaceArray;
 my @DeleteArray;
 my @AddArray;

 push @AddArray, 'cn', "me myself";
 push @ReplaceArray, 'sn', '!@#$%^&*()__+Hello THere';
 push @ReplaceArray, 'cn', "me myself I";
 push @DeleteArray, 'cn', "me myself";

 if ( $#ReplaceArray > 0 ) {
   push @whatToChange, 'replace';
   push @whatToChange, \@ReplaceArray;
 }
 if ( $#DeleteArray > 0 ) {
   push @whatToChange, 'delete';
   push @whatToChange, \@DeleteArray;
 }
 if ( $#AddArray > 0 ) {
   push @whatToChange, 'add';
   push @whatToChange, \@AddArray;
 }

 $result = LDAPmodify ( $ldap, $dn, \@whatToChange );

 sub LDAPmodify
 {
   my ($ldap, $dn, $whatToChange) = @_;

   my $result = $ldap->modify ( $dn,
                                changes => [
                                  @$whatToChange
                                ]
                              );
   return $result;
 }

 my $newRDN = "cn=Joseph User";

 my $result = LDAPrdnChange ( $ldap, $dn, $newRDN, "archive" );

 sub LDAPrdnChange
 {
   my ($ldap,$dn,$whatToChange,$action) = @_;

   my $branch;

   #
   # if the archive action is selected, move this
   # entry to another place in the directory.
   #
   if ( $action =~ /archive/i )  {
     $branch = "ou=newbranch, o=mycompany, c=mycountry";
   }

   #
   # use the 'deleteoldrdn' to keep from getting
   # multivalues in the NAMING attribute.
   # in most cases that would be the 'CN' attribute
   #
   my $result = $ldap->moddn ( $dn,
                               newrdn => $whatToChange,
                               deleteoldrdn => '1',
                               newsuperior => $branch
                             );

   return $result;

 }

 my $DNbranch = "ou=bailiwick, o=mycompany, c=mycountry";

 #
 # check with your Directory Schema or Administrator
 # for the correct objectClass... I'm sure it'll be different
 #
 my $CreateArray = [
   objectClass => [ "top", "person", "organizationalPerson", "inetOrgPerson" ],
   cn => "Jane User",
   uid => "0000001",
   sn => "User",
   mail => "JaneUser@mycompany.com"
 ];

 #
 # create the  new DN to look like this
 # " cn=Jo User + uid=0000001 , ou=bailiwick, o=mycompany, c=mycountry "
 #
 # NOTE: this DN  MUST be changed to meet your implementation
 #

 my $NewDN = "@$CreateArray[2]=".
             "@$CreateArray[3]+".
             "@$CreateArray[4]=".
             "@$CreateArray[5],".
             $DNbranch;

 LDAPentryCreate($ldap, $NewDN, $CreateArray);

 #
 # CreateArray is a reference to an anonymous array
 # you have to dereference it in the  subroutine it's
 # passed to.
 #

 sub LDAPentryCreate
 {
    my ($ldap, $dn, $whatToCreate) = @_;
    my $result = $ldap->add ( $dn, attrs => [ @$whatToCreate ] );
    return $result;
 }

 if ( $result->code ) {
   #
   # if we've got an error... record it
   #
   LDAPerror ( "Searching", $result );
 }

 sub LDAPerror
 {
   my ($from, $mesg) = @_;
   print "Return code: ", $mesg->code;
   print "\tMessage: ", $mesg->error_name;
   print " :",          $mesg->error_text;
   print "MessageID: ", $mesg->mesg_id;
   print "\tDN: ", $mesg->dn;

   #---
   # Programmer note:
   #
   #  "$mesg->error" DOESN'T work!!!
   #
   #print "\tMessage: ", $mesg->error;
   #-----
 }

 $ldap->unbind;

The following code snippet shows how to retrieve schema information.

The first procedure is to initialize a new LDAP object using the same procedures as listed at the beginning of this document.

The second procedure is to bind to your directory server. Some servers may require authentication to retrieve the schema from the directory server. This procedure is listed at the beginning of this document too.

After a successful bind you are ready to retrieve the schema information. You do this by initializing a schema object.

 $schema = $ldap->schema ( );

In this case Net::LDAP will attempt to determine the dn under which the schema can be found. First it will look for the attribute CWsubschemasubentry in the root DSE. If that cannot be found then it will default to the assumption of CWcn=schema

Alternatively you can specify the dn where the schema is to be found with

 $schema = $ldap->schema ( dn => $dn );

Once we have a dn to search for, Net::LDAP will fetch the schema entry with

  $mesg = $self->search ( base   => $dn,
                          scope  => 'base',
                          filter => '(objectClass=subschema)',
                        );

Once the schema object has been initialized, schema methods are used to retrieve the data. There are a number of ways this can be done. Information on the schema methods can be found in the Net::LDAP::Schema pod documentation.

The following is a code snippet showing how to get and display information about returned attributes.

 #
 # Get the attributes
 #

 @attributes = $schema->all_attributes ( );

 #
 # Display the attributes
 #

 foreach $ar ( @attributes ) {
   print "attributeType: ", $ar->{name}, "\n";

   #
   # Print all the details
   #

   foreach $key ( keys %{$ar} ) {
     print join ( "\n\t\t", "\t$key:",
                  ref ( $ar->{$key} ) ? @{$ar->{$key}} : $ar->{$key}
                ), "\n";
   }
 }

The process is the basically the same for getting objectClass information. Where schema->all_attributes() is used, substitute schema->all_objectclasses(). From that point on the process is the same for both objectClasses and attributes.

None known, but there may be some

Russell Biggs <rgb@ticnet.com>

All rights to this document are hereby relinquished to Graham Barr.