AT RISK the three limits, first reached per Aug 18 mtg
authorJohn Arwe
Fri, 22 Aug 2014 14:35:06 -0400
changeset 753 2fc23952cba1
parent 748 201bc5d76096
child 754 d0fbd3f227c5
AT RISK the three limits, first reached per Aug 18 mtg
ldp-paging.html
--- a/ldp-paging.html	Thu Aug 21 16:55:54 2014 -0400
+++ b/ldp-paging.html	Fri Aug 22 14:35:06 2014 -0400
@@ -245,6 +245,17 @@
 		included sections that covered the content now in this document.
 		For changes since its last publication, see <a href="#history" class="sectionRef"></a>. 
    </p>
+   <p>The following features are At Risk:</p>
+   <ol>
+   <li>The requirement to make LDP clients <a href="#atrisk-paging">paging-aware</a></a>.
+	</li>
+   <li>The <a href="#atrisk-units"><code>max-member-count</code> and <code>max-kbyte-count</code> preference parameters</a>, 
+		that allows clients to hint at acceptable page sizes.  Based on feedback, either or both might be removed or
+		changed to optional prior to the PR draft.
+	</li>
+   <li>The behavior of LDP Paging servers when <a href="#atrisk-paging-multiple-units">multiple page size hints are provided</a>.
+	</li>
+   </ol>
  </section>
  
 <section class="informative" id="intro">
@@ -1139,8 +1150,26 @@
 		</ul>
 	</p>
 
+	<div class="atrisk" id="atrisk-paging"><p class="atrisktext">Feature At Risk</p>
+	<p>The LDP Working Group proposes incorporation of the following clause to make LDP clients paging aware:</p>
+	<section id="ldpr-cli-paging"><h2 class="normal">
+		<a title="LDP client">LDP clients</a> SHOULD 
+		be capable of processing successful HTTP <code>GET</code> responses formed by a LDP server
+		that independently initiated paging, returning a page of representation instead of full resource
+		representation [[!LDP-PAGING]].
+	</h2>
+	</section> 
+	</div>
+	
+	<div class="atrisk" id="atrisk-units"><p class="atrisktext">Feature At Risk</p>
+	<p>The LDP Working Group proposes incorporation of the preference parameters
+		<code>max-member-count</code> and <code>max-kbyte-count</code>, along with
+		corresponding requirements on servers to support them.
+	</p>
+	</div>
+	
 	<p>
-		LDP Paging defines <code>max-triple-count</code>, <code>max-record-count</code>, and <code>max-kbyte-count</code> 
+		LDP Paging defines <code>max-triple-count</code>, <code>max-member-count</code>, and <code>max-kbyte-count</code> 
 		as new parameters on the existing 
 		HTTP <code>Prefer</code> request header's
 		<code>return=representation</code> preference [[!RFC7240]]; the presence of any of these parameters
@@ -1149,17 +1178,26 @@
 		A client communicates its hint(s) to the server by adding the
 		request header with a 
 		<code>return=representation</code> preference that includes any of the following preference parameters
-		<pre><code>"max-triple-count" *WSP "=" *WSP DQUOTE *WSP 1*DIGIT *WSP 
-"max-record-count" *WSP "=" *WSP DQUOTE *WSP 1*DIGIT *WSP DQUOTE
-"max-kbyte-count"  *WSP "=" *WSP DQUOTE *WSP 1*DIGIT *WSP DQUOTE</code></pre>
+		<table class="indented">
+		<tr>
+		<td> <code>max-triple-count</code> </td>
+		<td> The maximum decimal number of triples the client wishes to appear on each page.  </td>
+		</tr>
+		<tr>
+		<td> <code>max-kbyte-count</code> </td>
+		<td> The maximum decimal number of kilobytes (1024 byte units) the client wishes to receive as the page's representation.  </td>
+		</tr>
+		<tr>
+		<td> <code>max-member-count</code> </td>
+		<td> The maximum decimal number of members the client wishes to appear on each page.
+				This parameter is only meaningful for paged containers.
+		</td>
+		</tr>
+		</table>
 		<blockquote>
 		<p>
-		<code>WSP</code> is whitespace [[!RFC5234]], 
-		<code>DIGIT</code> is an integer between zero and nine [[!RFC5234]],
-		and
-		<code>DQUOTE</code> is a double quote [[!RFC5234]].
 		The generic preference BNF [[!RFC7240]] allows either a quoted string or a token as the value of a 
-		preference parameter; LDP Paging assigns a meaning to the value only when it is a quoted string.
+		preference parameter.
 		</p>
 		</blockquote>
 	</p>
@@ -1275,7 +1313,7 @@
 
 	<section id="ldpp-prefer-unrecognized"><h2 class="normal">
 		<a title="LDP Paging server">LDP Paging servers</a> MAY 
-		ignore a <a href="#ldpp-hints">page size</a> of zero, or unrecognized <a href="#ldpp-hints"><code>units</code></a>, 
+		ignore a <a href="#ldpp-hints">page size hints</a> whose value is zero, 
 		and process the request as if no maximum desired size was specified; in the latter case the server
 		can select whatever page size it deems appropriate, or choose not to page the resource at all.
 	</h2></section>
@@ -1339,7 +1377,7 @@
 			</li>
 			<li>
 				If the server is willing to provide a non-paged representation, respond
-				with an appropropriate status code (likely <code>200 OK</code>) and the potentially large
+				with an appropriate status code (likely <code>200 OK</code>) and the potentially large
 				non-paged representation.
 			</li>
 			<li>
@@ -1541,6 +1579,46 @@
 			paging link response headers, for example, rel='first'.
 		</h2></section><!-- #ldpr-pagingGET-abandon-pageseq -->
 
+		<!-- 
+		<div class="atrisk" id="atrisk-paging-triple-count"><p class="atrisktext">Feature At Risk</p>
+		<p>The LDP Working Group proposes incorporation of the following clause:</p>
+		 -->
+		<section id="ldpr-units-triple-count"><h2 class="normal">
+			<a title="LDP Paging server">LDP Paging servers</a> MUST
+			support the <code>max-triple-count</code> <a href="#ldpp-hints">client preference parameter</a>,
+			which expresses a page size limiting the number of RDF triples represented on a page.
+			For example, <code>max-triple-count="500"</code> expresses a limit of 500 RDF triples per page.
+		</h2>
+		</section> 
+		<!-- 
+		</div>
+		 -->
+	
+		<div class="atrisk" id="atrisk-paging-kbyte-count"><p class="atrisktext">Feature At Risk</p>
+		<p>The LDP Working Group proposes incorporation of the following clause:</p>
+		<section id="ldpr-units-kbyte-count"><h2 class="normal">
+			<a title="LDP Paging server">LDP Paging servers</a> MUST
+			support the <code>max-kbyte-count</code> <a href="#ldpp-hints">client preference parameter</a>,
+			which expresses a page size limit as kilobytes of representation size.
+			For example, <code>max-kbyte-count="1"</code> expresses a limit of 1024 bytes per page.
+		</h2>
+		</section> 
+		</div>
+	
+		<div class="atrisk" id="atrisk-paging-multiple-units"><p class="atrisktext">Feature At Risk</p>
+		<p>The LDP Working Group proposes incorporation of the following clause:</p>
+		<section id="ldpr-pagesize-multiple-units"><h2 class="normal">
+			<a title="LDP Paging server">LDP Paging servers</a> MUST, if provided with multiple 
+			 <a href="#ldpp-hints">client preference parameters</a> limiting page size,
+			honor all hints that it recognizes.  This has the net effect that the most restrictive
+			hint for any given response governs the resulting page size.
+			For example, <code>max-kbyte-count="1"</code> and <code>max-triple-count="500"</code>
+			usually would result in pages with fewer than 500 triples, since each triple very likely
+			requires more than two bytes (500 triples/1024 bytes).
+		</h2>
+		</section> 
+		</div>
+	
 		<!-- combined into ldpr-status-code
 		<section id="ldpr-pagingGET-only-paging-clients"><h2 class="normal">
 			<a title="LDP Paging server">LDP Paging servers</a> SHOULD NOT
@@ -1589,6 +1667,17 @@
 		for a <a title="paged resource">paged LDPC</a>.
 	</h2></section>
 	
+	<div class="atrisk" id="atrisk-paging-record-count"><p class="atrisktext">Feature At Risk</p>
+	<p>The LDP Working Group proposes incorporation of the following clause:</p>
+	<section id="ldpr-units-record-count"><h2 class="normal">
+		<a title="LDP Paging server">LDP Paging servers</a> MUST
+		support the <code>max-member-count</code> <a href="#ldpp-hints">client preference parameter</a>,
+		which expresses a page size limiting the number of members returned on each page of a <a title="paged resource">paged LDPC</a>.
+		For example, <code>max-member-count="10"</code> expresses a limit of 10 members per page.
+	</h2>
+	</section> 
+	</div>
+	
 </section>
 
 <section class="informative" id="ldpc-informative">		
@@ -2129,7 +2218,8 @@
 <!-- <blockquote><em><a href="http://www.w3.org/TR/2013/WD-ldp-paging-20140930/">Candidate Recommendation Draft</a></em></blockquote> wah -->
 <!-- <blockquote><em><a href="http://www.w3.org/TR/2013/WD-ldp-paging-20140730/">Last Call Draft</a></em></blockquote> -->
 <ul>
-	<li>2014-08-21 - max-triple-count, max-record-count, max-kbyte-count with parms being integers per Aug 18 mtg (JA) </li>
+	<li>2014-08-22 - AT RISK the three limits, first reached per Aug 18 mtg (JA) </li>
+	<li>2014-08-21 - max-triple-count, max-member-count, max-kbyte-count with parms being integers per Aug 18 mtg (JA) </li>
 	<li>2014-08-05 - Re-cast sort criteria as rdf:List compatible with syntactic sugar for those (JA) </li>
 	<li>2014-08-05 - Fuss SOTD for Arnaud (JA) </li>
 	<li>2014-08-04 - Fuss with SortValueAscending value for Sandro (JA) </li>