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740 lines
34 KiB
Plaintext
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Internet-Draft D. Boreham, Bozeman Pass
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LDAPext Working Group J. Sermersheim, Novell
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Intended Category: Standards Track A. Kashi, Microsoft
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<draft-ietf-ldapext-ldapv3-vlv-09.txt>
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Expires: Jun 2003 Nov 2002
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LDAP Extensions for Scrolling View Browsing of Search Results
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1. Status of this Memo
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This document is an Internet-Draft and is in full conformance with
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all provisions of Section 10 of RFC2026.
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Internet-Drafts are working documents of the Internet Engineering
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Task Force (IETF), its areas, and its working groups. Note that other
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groups may also distribute working documents as Internet-Drafts.
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Internet-Drafts are draft documents valid for a maximum of six months
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and may be updated, replaced, or obsoleted by other documents at any
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time. It is inappropriate to use Internet-Drafts as reference
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material or to cite them other than as "work in progress."
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The list of current Internet-Drafts can be accessed at
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http://www.ietf.org/ietf/1id-abstracts.txt
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The list of Internet-Draft Shadow Directories can be accessed at
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http://www.ietf.org/shadow.html.
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This document is intended to be submitted, after review and revision,
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as a Standards Track document. Distribution of this memo is
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unlimited.
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Please send comments to the authors.
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2. Abstract
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This document describes a Virtual List View extension for the
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Lightweight Directory Access Protocol (LDAP) Search operation. This
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extension is designed to allow the "virtual list box" feature, common
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in existing commercial e-mail address book applications, to be
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supported efficiently by LDAP servers. LDAP servers' inability to
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support this client feature is a significant impediment to LDAP
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replacing proprietary protocols in commercial e-mail systems.
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The extension allows a client to specify that the server return, for
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a given LDAP search with associated sort keys, a contiguous subset of
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the search result set. This subset is specified in terms of offsets
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into the ordered list, or in terms of a greater than or equal
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comparison value.
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Boreham et al Internet-Draft 1
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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3. Conventions used in this document
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The key words "MUST", "SHALL", "SHOULD", "SHOULD NOT", and "MAY" in
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this document are to be interpreted as described in RFC 2119
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[Bradner97].
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Protocol elements are described using ASN.1 [X.680]. The term "BER-
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encoded" means the element is to be encoded using the Basic Encoding
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Rules [X.690] under the restrictions detailed in Section 5.1 of
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[LDAPPROT].
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The phrase "subsequent virtual list request" is used in this document
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to describe a search request accompanied by a VirtualListViewRequest
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control, where the search base, scope, and filter are the same as a
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previous search request also accompanied by a VirtualListViewRequest
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control, and where the contextID of the subsequent
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VirtualListViewRequest control, is set to that of the contextID in
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the VirtualListViewResponse control that accompanied the previous
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search response.
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The phrase "contiguous virtual list request" is used to describe a
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subsequent virtual list request which is requesting search results
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adjoining or overlapping the result returned from the prior virtual
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list request.
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4. Background
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A Virtual List is a graphical user interface technique employed where
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ordered lists containing a large number of entries need to be
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displayed. A window containing a small number of visible list entries
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is drawn. The visible portion of the list may be relocated to
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different points within the list by means of user input. This input
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can be to a scroll bar slider; from cursor keys; from page up/down
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keys; from alphanumeric keys for "typedown". The user is given the
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impression that they may browse the complete list at will, even
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though it may contain millions of entries. It is the fact that the
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complete list contents are never required at any one time that
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characterizes Virtual List View. Rather than fetch the complete list
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from wherever it is stored (typically from disk or a remote server),
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only that information which is required to display the part of the
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list currently in view is fetched. The subject of this document is
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the interaction between client and server required to implement this
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functionality in the context of the results from an ordered [SSS]
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Lightweight Directory Access Protocol (LDAP) search operation
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[LDAPPROT].
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For example, suppose an e-mail address book application displays a
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list view onto the list containing the names of all the holders of e-
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mail accounts at a large university. The list is ordered
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alphabetically. While there may be tens of thousands of entries in
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this list, the address book list view displays only 20 such accounts
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Boreham et al Internet-Draft 2
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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at any one time. The list has an accompanying scroll bar and text
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input window for type-down. When first displayed, the list view shows
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the first 20 entries in the list, and the scroll bar slider is
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positioned at the top of its range. Should the user drag the slider
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to the bottom of its range, the displayed contents of the list view
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should be updated to show the last 20 entries in the list. Similarly,
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if the slider is positioned somewhere in the middle of its travel,
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the displayed contents of the list view should be updated to contain
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the 20 entries located at that relative position within the complete
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list. Starting from any display point, if the user uses the cursor
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keys or clicks on the scroll bar to request that the list be scrolled
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up or down by one entry, the displayed contents should be updated to
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reflect this. Similarly the list should be displayed correctly when
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the user requests a page scroll up or down. Finally, when the user
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types characters in the type-down window, the displayed contents of
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the list should "jump" or "seek" to the appropriate point within the
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list. For example, if the user types "B", the displayed list could
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center around the first user with a name beginning with the letter
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"B". When this happens, the scroll bar slider should also be updated
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to reflect the new relative location within the list.
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This document defines a request control which extends the LDAP search
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operation. Always used in conjunction with the server side sorting
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control [SSS], this allows a client to retrieve selected portions of
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large search result set in a fashion suitable for the implementation
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of a virtual list view.
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5. Client-Server Interaction
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The Virtual List View control extends a regular LDAP Search operation
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which MUST also include a server-side sorting control [SSS]. Rather
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than returning the complete set of appropriate SearchResultEntry
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messages, the server is instructed to return a contiguous subset of
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those entries, taken from the ordered result set, centered around a
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particular target entry. Henceforth, in the interests of brevity, the
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ordered search result set will be referred to as "the list".
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The sort control may contain any sort specification valid for the
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server. The attributeType field in the first SortKeyList sequence
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element has special significance for "typedown". The Virtual List
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View control acts upon a set of ordered entries and this order must
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be repeatable for all subsequent virtual list requests. The server-
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side sorting control is intended to aid in this ordering, but other
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mechanisms may need to be employed to produce a repeatable order--
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especially for entries that don't have a value of the sort key.
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The desired target entry and the number of entries to be returned,
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both before and after that target entry in the list, are determined
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by the client's VirtualListViewRequest control.
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Boreham et al Internet-Draft 3
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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When the server returns the set of entries to the client, it attaches
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a VirtualListViewResponse control to the SearchResultDone message.
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The server returns in this control: its current estimate for the list
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content count, the location within the list corresponding to the
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target entry, any error codes, and optionally a context identifier.
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The target entry is specified in the VirtualListViewRequest control
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by one of two methods. The first method is for the client to indicate
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the target entry's offset within the list. The second way is for the
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client to supply an attribute assertion value. The value is compared
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against the values of the attribute specified as the primary sort key
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in the sort control attached to the search operation. The first sort
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key in the SortKeyList is the primary sort key. The target entry is
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the first entry in the list with value greater than or equal to (in
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the primary sort order), the presented value. The order is determined
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by rules defined in [SSS]. Selection of the target entry by this
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means is designed to implement "typedown". Note that it is possible
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that no entry satisfies these conditions, in which case there is no
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target entry. This condition is indicated by the server returning the
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special value contentCount + 1 in the target position field.
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Because the server may not have an accurate estimate of the number of
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entries in the list, and to take account of cases where the list size
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is changing during the time the user browses the list, and because
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the client needs a way to indicate specific list targets "beginning"
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and "end", offsets within the list are transmitted between client and
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server as ratios---offset to content count. The server sends its
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latest estimate as to the number of entries in the list (content
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count) to the client in every response control. The client sends its
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assumed value for the content count in every request control. The
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server examines the content count and offsets presented by the client
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and computes the corresponding offsets within the list, based on its
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own idea of the content count.
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Si = Sc * (Ci / Cc)
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Where:
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Si is the actual list offset used by the server
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Sc is the server's estimate for content count
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Ci is the client's submitted offset
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Cc is the client's submitted content count
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The result is rounded to the nearest integer.
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If the content count is stable, and the client returns to the server
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the content count most recently received, Cc = Sc and the offsets
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transmitted become the actual server list offsets.
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The following special cases exist when the client is specifying the
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offset and content count:
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- an offset of one and a content count of non-one (Ci = 1, Cc != 1)
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indicates that the target is the first entry in the list.
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Boreham et al Internet-Draft 4
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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- equivalent values (Ci = Cc) indicate that the target is the last
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entry in the list.
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- a content count of zero (Cc = 0, Ci != 0) means the client has no
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idea what the content count is, the server MUST use its own
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content count estimate in place of the client's.
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Because the server always returns contentCount and targetPosition,
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the client can always determine which of the returned entries is the
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target entry. Where the number of entries returned is the same as the
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number requested, the client is able to identify the target by simple
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arithmetic. Where the number of entries returned is not the same as
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the number requested (because the requested range crosses the
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beginning or end of the list, or both), the client MUST use the
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target position and content count values returned by the server to
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identify the target entry. For example, suppose that 10 entries
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before and 10 after the target were requested, but the server returns
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13 entries, a content count of 100 and a target position of 3. The
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client can determine that the first entry must be entry number 1 in
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the list, therefore the 13 entries returned are the first 13 entries
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in the list, and the target is the third one.
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A server-generated contextID MAY be returned to clients. A client
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receiving a contextID MUST return it unchanged or not return it at
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all, in a subsequent request which relates to the same list. The
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purpose of this interaction is to maintain state information between
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the client and server.
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6. The Controls
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Support for the virtual list view control extension is indicated by
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the presence of the OID "2.16.840.1.113730.3.4.9" in the
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supportedControl attribute of a server's root DSE.
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6.1. Request Control
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This control is included in the SearchRequest message as part of the
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controls field of the LDAPMessage, as defined in Section 4.1.12 of
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[LDAPPROT]. The controlType is set to "2.16.840.1.113730.3.4.9". If
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this control is included in a SearchRequest message, a Server Side
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Sorting request control [SSS] MUST also be present in the message.
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The controlValue, an OCTET STRING, is the BER-encoding of the
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following SEQUENCE:
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VirtualListViewRequest ::= SEQUENCE {
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beforeCount INTEGER (0..maxInt),
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afterCount INTEGER (0..maxInt),
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target CHOICE {
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byOffset [0] SEQUENCE {
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offset INTEGER (1 .. maxInt),
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contentCount INTEGER (0 .. maxInt) },
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Boreham et al Internet-Draft 5
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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greaterThanOrEqual [1] AssertionValue },
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contextID OCTET STRING OPTIONAL }
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beforeCount indicates how many entries before the target entry the
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client wants the server to send.
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afterCount indicates the number of entries after the target entry the
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client wants the server to send.
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offset and contentCount identify the target entry as detailed in
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section 5.
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greaterThanOrEqual is a matching rule assertion value defined in
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[LDAPPROT]. The assertion value is encoded according to the ORDERING
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matching rule for the attributeDescription in the sort control [SSS].
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If present, the value supplied in greaterThanOrEqual is used to
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determine the target entry by comparison with the values of the
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attribute specified as the primary sort key. The first list entry
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who's value is no less than (less than or equal to when the sort
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order is reversed) the supplied value is the target entry.
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If present, the contextID field contains the value of the most
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recently received contextID field from a VirtualListViewResponse
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control for the same list view. If the contextID is not known because
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no contextID has been sent by the server in a VirtualListViewResponse
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control, it SHALL be omitted. If the server receives a contextID that
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is invalid, it SHALL fail the search operation and indicate the
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failure with a protocolError (3) value in the virtualListViewResult
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field of the VirtualListViewResponse. The contextID provides state
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information between the client and server. This state information is
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used by the server to ensure continuity contiguous virtual list
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requests. When a server receives a VirtualListViewRequest control
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that includes a contextID, it SHALL determine whether the client has
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sent a contiguous virtual list request and SHALL provide contiguous
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entries if possible. If a valid contextID is sent, and the server is
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unable to determine whether contiguous data is requested, or is
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unable to provide requested contiguous data, it SHALL fail the search
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operation and indicate the failure with an unwillingToPerform (53)
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value in the virtualListViewResult field of the
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VirtualListViewResponse. contextID values have no validity outside
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the connection and query with which they were received. A client MUST
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NOT submit a contextID which it received from a different connection,
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a different query, or a different server.
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The type AssertionValue and value maxInt are defined in [LDAPPROT].
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6.2. Response Control
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Boreham et al Internet-Draft 6
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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If the request control is serviced, this response control is included
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in the SearchResultDone message as part of the controls field of the
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LDAPMessage, as defined in Section 4.1.12 of [LDAPPROT].
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The controlType is set to "2.16.840.1.113730.3.4.10". The
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controlValue, an OCTET STRING, is the BER-encoding of the following
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SEQUENCE:
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VirtualListViewResponse ::= SEQUENCE {
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targetPosition INTEGER (0 .. maxInt),
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contentCount INTEGER (0 .. maxInt),
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virtualListViewResult ENUMERATED {
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success (0),
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operationsError (1),
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protocolError (3),
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unwillingToPerform (53),
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insufficientAccessRights (50),
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timeLimitExceeded (3),
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adminLimitExceeded (11),
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innapropriateMatching (18),
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sortControlMissing (60),
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offsetRangeError (61),
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other(80),
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... },
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contextID OCTET STRING OPTIONAL }
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targetPosition gives the list offset for the target entry.
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contentCount gives the server's estimate of the current number of
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entries in the list. Together these give sufficient information for
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the client to update a list box slider position to match the newly
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retrieved entries and identify the target entry. The contentCount
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value returned SHOULD be used in a subsequent VirtualListViewRequest
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control.
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contextID is a server-defined octet string. If present, the contents
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of the contextID field SHOULD be returned to the server by a client
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in a subsequent virtual list request. The presence of a contextID
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here indicates that the server is willing to return contiguous data
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from a subsequent search request which uses the same search criteria,
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accompanied by a VirtualListViewRequest which indicates that the
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client wishes to receive an adjoining page of data.
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The virtualListViewResult codes which are common to the LDAP
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searchResultDone (adminLimitExceeded, timeLimitExceeded,
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operationsError, unwillingToPerform, insufficientAccessRights,
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success, other) have the same meanings as defined in [LDAPPROT], but
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they pertain specifically to the VLV operation. For example, the
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server could exceed a VLV-specific administrative limit while
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processing a SearchRequest with a VirtualListViewRequest control.
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Obviously, the same administrative limit would not be exceeded should
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Boreham et al Internet-Draft 7
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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the same SearchRequest be submitted by the client without the
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VirtualListViewRequest control. In this case, the client can
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determine that the administrative limit has been exceeded in
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servicing the VLV request, and can if it chooses resubmit the
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SearchRequest without the VirtualListViewRequest control, or with
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different parameters.
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insufficientAccessRights means that the server denied the client
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permission to perform the VLV operation.
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If the server determines that the results of the search presented
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exceed the range specified in INTEGER values, or if the client
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specifies an invalid offset or contentCount, the server MUST set the
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virtualListViewResult value to offsetRangeError.
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6.2.1 virtualListViewError
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A new LDAP error is introduced called virtualListViewError. Its value
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is 76. This error indicates that the search operation failed due to
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the inclusion of the VirtualListViewRequest control.
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If the resultCode in the SearchResultDone message is set to
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virtualListViewError (76), then the virtualListViewResult value MUST
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NOT be success (as virtualListViewResult indicates the specific error
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condition). If resultCode in the SearchResultDone message is not set
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to virtualListViewError (76), then the virtualListViewResult value
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SHOULD be success (0) and its value MUST be ignored.
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7. Protocol Example
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Here we walk through the client-server interaction for a specific
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virtual list view example: The task is to display a list of all 78564
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persons in the US company "Ace Industry". This will be done by
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creating a graphical user interface object to display the list
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contents, and by repeatedly sending different versions of the same
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virtual list view search request to the server. The list view
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displays 20 entries on the screen at a time.
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We form a search with baseObject of "o=Ace Industry,c=us"; scope of
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wholeSubtree; and filter of "(objectClass=person)". We attach a
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server-side sort control [SSS] to the search request, specifying
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ascending sort on attribute "cn". To this search request, we attach a
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virtual list view request control with contents determined by the
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user activity and send the search request to the server. We display
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the results from each search result entry in the list window and
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update the slider position.
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When the list view is first displayed, we want to initialize the
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contents showing the beginning of the list. Therefore, we set
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beforeCount to 0, afterCount to 19, contentCount to 0, offset to 1
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and send the request to the server. The server duly returns the first
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Boreham et al Internet-Draft 8
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LDAP Extensions for Scrolling View Nov 2002
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Browsing of Search Results
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20 entries in the list, plus a content count of 78564 and
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targetPosition of 1. We therefore leave the scroll bar slider at its
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current location (the top of its range).
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Say that next the user drags the scroll bar slider down to the bottom
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of its range. We now wish to display the last 20 entries in the list,
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so we set beforeCount to 19, afterCount to 0, contentCount to 78564,
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offset to 78564 and send the request to the server. The server
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returns the last 20 entries in the list, plus a content count of
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78564 and a targetPosition of 78564.
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Next the user presses a page up key. Our page size is 20, so we set
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beforeCount to 0, afterCount to 19, contentCount to 78564, offset to
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78564-19-20 and send the request to the server. The server returns
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the preceding 20 entries in the list, plus a content count of 78564
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and a targetPosition of 78525.
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|
||
Now the user grabs the scroll bar slider and drags it to 68% of the
|
||
way down its travel. 68% of 78564 is 53424 so we set beforeCount to
|
||
9, afterCount to 10, contentCount to 78564, offset to 53424 and send
|
||
the request to the server. The server returns the preceding 20
|
||
entries in the list, plus a content count of 78564 and a
|
||
targetPosition of 53424.
|
||
|
||
Lastly, the user types the letter "B". We set beforeCount to 9,
|
||
afterCount to 10 and greaterThanOrEqual to "B". The server finds the
|
||
first entry in the list not less than "B", let's say "Babs Jensen",
|
||
and returns the nine preceding entries, the target entry, and the
|
||
proceeding 10 entries. The server returns a content count of 78564
|
||
and a targetPosition of 5234 and so the client updates its scroll bar
|
||
slider to 6.7% of full scale.
|
||
|
||
|
||
8. Notes for Implementers
|
||
|
||
While the feature is expected to be generally useful for arbitrary
|
||
search and sort specifications, it is specifically designed for those
|
||
cases where the result set is very large. The intention is that this
|
||
feature be implemented efficiently by means of pre-computed indices
|
||
pertaining to a set of specific cases. For example, an offset
|
||
relating to "all the employees in the local organization, sorted by
|
||
surname" would be a common case.
|
||
|
||
The intention for client software is that the feature should fit
|
||
easily with the host platform's graphical user interface facilities
|
||
for the display of scrolling lists. Thus the task of the client
|
||
implementers should be one of reformatting up the requests for
|
||
information received from the list view code to match the format of
|
||
the virtual list view request and response controls.
|
||
|
||
|
||
|
||
Boreham et al Internet-Draft 9
|
||
|
||
LDAP Extensions for Scrolling View Nov 2002
|
||
Browsing of Search Results
|
||
|
||
Client implementers MUST be aware that any offset value returned by
|
||
the server might be approximate. Do not design clients that only
|
||
operate correctly when offsets are exact. However, if contextIDs are
|
||
used, and adjoining pages of information are requested, the server
|
||
will return contiguous data.
|
||
|
||
Server implementers using indexing technology which features
|
||
approximate positioning should consider returning contextIDs to
|
||
clients. The use of a contextID will allow the server to distinguish
|
||
between client requests which relate to different displayed lists on
|
||
the client. Consequently the server can decide more intelligently
|
||
whether to reposition an existing database cursor accurately to
|
||
within a short distance of its current position, or to reposition to
|
||
an approximate position. Thus the client will see precise offsets for
|
||
"short" repositioning (e.g. paging up or down), but approximate
|
||
offsets for a "long" reposition (e.g. a slider movement).
|
||
|
||
Server implementers are free to return an LDAP result code of
|
||
virtualListViewError and a virtualListViewResult of
|
||
unwillingToPerform should their server be unable to service any
|
||
particular VLV search. This might be because the resolution of the
|
||
search is computationally infeasible, or because excessive server
|
||
resources would be required to service the search.
|
||
|
||
Client implementers should note that this control is only defined on
|
||
a client interaction with a single server. If a search scope spans
|
||
multiple naming contexts that are not held locally, search result
|
||
references will be returned, and may occur at any point in the search
|
||
operation. The client is responsible for deciding when and how to
|
||
apply this control to the referred-to servers, and how to collate the
|
||
results from multiple servers.
|
||
|
||
|
||
9. Relationship to "Simple Paged Results"
|
||
|
||
These controls are designed to support the virtual list view, which
|
||
has proved hard to implement with the Simple Paged Results mechanism
|
||
[SPaged]. However, the controls described here support any operation
|
||
possible with the Simple Paged Results mechanism. The two mechanisms
|
||
are not complementary; rather one has a superset of the other's
|
||
features. One area where the mechanism presented here is not a strict
|
||
superset of the Simple Paged Results scheme is that here we require a
|
||
sort order to be specified. No such requirement is made for paged
|
||
results.
|
||
|
||
|
||
10. Security Considerations
|
||
|
||
Server implementers may wish to consider whether clients are able to
|
||
consume excessive server resources in requesting virtual list
|
||
operations. Access control to the feature itself; configuration
|
||
|
||
Boreham et al Internet-Draft 10
|
||
|
||
LDAP Extensions for Scrolling View Nov 2002
|
||
Browsing of Search Results
|
||
|
||
options limiting the feature's use to certain predetermined search
|
||
base DNs and filters; throttling mechanisms designed to limit the
|
||
ability for one client to soak up server resources, may be
|
||
appropriate.
|
||
|
||
Consideration should be given as to whether a client will be able to
|
||
retrieve the complete contents, or a significant subset of the
|
||
complete contents of the directory using this feature. This may be
|
||
undesirable in some circumstances and consequently it may be
|
||
necessary to enforce some access control or administrative limit.
|
||
|
||
Clients can, using this control, determine how many entries match a
|
||
particular filter, before the entries are returned to the client.
|
||
This may require special processing in servers which perform access
|
||
control checks on entries to determine whether the existence of the
|
||
entry can be disclosed to the client.
|
||
|
||
Server implementers should exercise caution concerning the content of
|
||
the contextID. Should the contextID contain internal server state, it
|
||
may be possible for a malicious client to use that information to
|
||
gain unauthorized access to information.
|
||
|
||
11. IANA Considerations
|
||
|
||
11.1 Request for LDAP Result Code
|
||
|
||
In accordance with section 3.6 of [LDAPIANA], it is requested that
|
||
IANA register the LDAP result code virtualListViewError (76) upon
|
||
Standards Action by the IESG. The value 76 has been suggested by
|
||
experts, had expert review, and is currently being used by some
|
||
implementations. If 76 is unavailable on not chosen, the value in the
|
||
paragraphs in Section 6.2.1 will need to be updated. The following
|
||
registration template is suggested:
|
||
|
||
Subject: LDAP Result Code Registration
|
||
Person & email address to contact for further information: Jim
|
||
Sermersheim
|
||
Result Code Name: virtualListViewError
|
||
Specification: RFCXXXX
|
||
Author/Change Controller: IESG
|
||
Comments: request LDAP result codes be assigned
|
||
|
||
|
||
|
||
12. Acknowledgements
|
||
|
||
Chris Weider, Anoop Anantha, and Michael Armijo of Microsoft co-
|
||
authored previous versions of this document.
|
||
|
||
|
||
|
||
|
||
Boreham et al Internet-Draft 11
|
||
|
||
LDAP Extensions for Scrolling View Nov 2002
|
||
Browsing of Search Results
|
||
|
||
13. Normative References
|
||
|
||
|
||
[X.680] ITU-T Rec. X.680, "Abstract Syntax Notation One (ASN.1) -
|
||
Specification of Basic Notation", 1994.
|
||
|
||
[X.690] ITU-T Rec. X.690, "Specification of ASN.1 encoding rules:
|
||
Basic, Canonical, and Distinguished Encoding Rules",
|
||
1994.
|
||
|
||
[LDAPPROT] Wahl, M., Kille, S. and T. Howes, "Lightweight Directory
|
||
Access Protocol (v3)", Internet Standard, RFC 2251,
|
||
December, 1997.
|
||
|
||
[SSS] Wahl, M., Herron, A. and T. Howes, "LDAP Control
|
||
Extension for Server Side Sorting of Search Results",
|
||
RFC 2891, August, 2000.
|
||
|
||
[Bradner97] Bradner, S., "Key Words for use in RFCs to Indicate
|
||
Requirement Levels", BCP 14, RFC 2119, March 1997.
|
||
|
||
[LDAPIANA] Zeilenga, K., "Internet Assigned Numbers Authority (IANA)
|
||
Considerations for the Lightweight Directory Access
|
||
Protocol (LDAP)", RFC 3383, September 2002.
|
||
|
||
14. Informative References
|
||
|
||
[SPaged] Weider, C., Herron, A., Anantha, A. and T. Howes, "LDAP
|
||
Control Extension for Simple Paged Results Manipulation",
|
||
RFC2696, September 1999.
|
||
|
||
|
||
15. Authors' Addresses
|
||
|
||
David Boreham
|
||
Bozeman Pass, Inc
|
||
+1 406 222 7093
|
||
david@bozemanpass.com
|
||
|
||
Jim Sermersheim
|
||
Novell
|
||
1800 South Novell Place
|
||
Provo, Utah 84606, USA
|
||
jimse@novell.com
|
||
|
||
Asaf Kashi
|
||
Microsoft Corporation
|
||
1 Microsoft Way
|
||
Redmond, WA 98052, USA
|
||
+1 425 882-8080
|
||
asafk@microsoft.com
|
||
|
||
Boreham et al Internet-Draft 12
|
||
|
||
LDAP Extensions for Scrolling View Nov 2002
|
||
Browsing of Search Results
|
||
|
||
|
||
|
||
16. Full Copyright Statement
|
||
|
||
Copyright (C) The Internet Society (2002). All Rights Reserved.
|
||
This document and translations of it may be copied and furnished to
|
||
others, and derivative works that comment on or otherwise explain it
|
||
or assist in its implementation may be prepared, copied, published
|
||
and distributed, in whole or in part, without restriction of any
|
||
kind, provided that the above copyright notice and this paragraph are
|
||
included on all such copies and derivative works. However, this
|
||
document itself may not be modified in any way, such as by removing
|
||
the copyright notice or references to the Internet Society or other
|
||
Internet organizations, except as needed for the purpose of
|
||
developing Internet standards in which case the procedures for
|
||
copyrights defined in the Internet Standards process must be
|
||
followed, or as required to translate it into languages other than
|
||
English. The limited permissions granted above are perpetual and will
|
||
not be revoked by the Internet Society or its successors or assigns.
|
||
This document and the information contained herein is provided on an
|
||
"AS IS" basis and THE INTERNET SOCIETY AND THE
|
||
INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR
|
||
IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
|
||
THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
|
||
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE."
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Boreham et al Internet-Draft 13
|