phpman > perldoc > Net::LDAP::Control::VLV(3pm)

NAME
    Net::LDAP::Control::VLV - LDAPv3 Virtual List View control object

SYNOPSIS
     use Net::LDAP;
     use Net::LDAP::Control::VLV;
     use Net::LDAP::Constant qw( LDAP_CONTROL_VLVRESPONSE );

     $ldap = Net::LDAP->new( "ldap.mydomain.eg" );

     # Get the first 20 entries
     $vlv  = Net::LDAP::Control::VLV->new(
               before  => 0,        # No entries from before target entry
               after   => 19,       # 19 entries after target entry
               content => 0,        # List size unknown
               offset  => 1,        # Target entry is the first
             );
     $sort = Net::LDAP::Control::Sort->new( order => 'cn' );

     @args = ( base     => "o=Ace Industry, c=us",
               scope    => "subtree",
               filter   => "(objectClass=inetOrgPerson)",
               callback => \&process_entry, # Call this sub for each entry
               control  => [ $vlv, $sort ],
     );

     $mesg = $ldap->search( @args );

     # Get VLV response control
     ($resp)  = $mesg->control( LDAP_CONTROL_VLVRESPONSE )  or die;
     $vlv->response( $resp );

     # Set the control to get the last 20 entries
     $vlv->end;

     $mesg = $ldap->search( @args );

     # Get VLV response control
     ($resp)  = $mesg->control( LDAP_CONTROL_VLVRESPONSE )  or die;
     $vlv->response( $resp );

     # Now get the previous page
     $vlv->scroll_page( -1 );

     $mesg = $ldap->search( @args );

     # Get VLV response control
     ($resp)  = $mesg->control( LDAP_CONTROL_VLVRESPONSE )  or die;
     $vlv->response( $resp );

     # Now page with first entry starting with "B" in the middle
     $vlv->before(9);       # Change page to show 9 before
     $vlv->after(10);       # Change page to show 10 after
     $vlv->assert("B");     # assert "B"

     $mesg = $ldap->search( @args );

DESCRIPTION
    "Net::LDAP::Control::VLV" provides an interface for the creation and manipulation of objects
    that represent the Virtual List View as described by draft-ietf-ldapext-ldapv3-vlv-09.txt.

    When using a Virtual List View control in a search, it must be accompanied by a sort control.
    See Net::LDAP::Control::Sort

CONSTRUCTOR ARGUMENTS
    In addition to the constructor arguments described in Net::LDAP::Control the following are
    provided.

    after
        Set the number of entries the server should return from the list after the target entry.

    assert
        Set the assertion value user to locate the target entry. This value should be a legal value
        to compare with the first attribute in the sort control that is passed with the VLV control.
        The target entry is the first entry in the list which is greater than or equal the assert
        value.

    before
        Set the number of entries the server should return from the list before the target entry.

    content
        Set the number of entries in the list. On the first search this value should be set to zero.
        On subsequent searches it should be set to the length of the list, as returned by the server
        in the VLVResponse control.

    context
        Set the context identifier. On the first search this value should be set to zero. On
        subsequent searches it should be set to the context value returned by the server in the
        VLVResponse control.

    offset
        Set the offset of the target entry.

  METHODS
    As with Net::LDAP::Control each constructor argument described above is also available as a
    method on the object which will return the current value for the attribute if called without an
    argument, and set a new value for the attribute if called with an argument.

    The "offset" and "assert" attributes are mutually exclusive. Setting one or the other will cause
    previous values set by the other to be forgotten. The "content" attribute is also associated
    with the "offset" attribute, so setting "assert" will cause any "content" value to be forgotten.

    end Set the target entry to the end of the list. This method will change the "before" and
        "after" attributes so that the target entry is the last in the page.

    response VLV_RESPONSE
        Set the attributes in the control as per VLV_RESPONSE. VLV_RESPONSE should be a control of
        type Net::LDAP::Control::VLVResponse returned from the server. "response" will populate the
        "context", "offset" and "content" attributes of the control with the values from
        VLV_RESPONSE. Because this sets the "offset" attribute, any previous setting of the "assert"
        attribute will be forgotten.

    scroll NUM
        Move the target entry by NUM entries. A positive NUM will move the target entry towards the
        end of the list and a negative NUM will move the target entry towards the start of the list.
        Returns the index of the new target entry, or "undef" if the current target is identified by
        an assertion.

        "scroll" may change the "before" and "after" attributes if the scroll value would cause the
        page to go off either end of the list. But the page size will be maintained.

    scroll_page NUM
        Scroll by NUM pages. This method simple calculates the current page size and calls "scroll"
        with "NUM * $page_size"

    start
        Set the target entry to the start of the list. This method will change the "before" and
        "after" attributes to the target entry is the first entry in the page.

SEE ALSO
    Net::LDAP, Net::LDAP::Control, Net::LDAP::Control::Sort, Net::LDAP::Control::VLVResponse

AUTHOR
    Graham Barr <gbarr AT pobox.com>

    Please report any bugs, or post any suggestions, to the perl-ldap mailing list
    <perl-ldap AT perl.org>

COPYRIGHT
    Copyright (c) 2000-2004 Graham Barr. All rights reserved. This program is free software; you can
    redistribute it and/or modify it under the same terms as Perl itself.