Add documentation about facets

[yaz-moved-to-github.git] / doc / zoom.xml

diff --git a/doc/zoom.xml b/doc/zoom.xml
index d1ccf8e..74c95f3 100644 (file)
--- a/doc/zoom.xml
+++ b/doc/zoom.xml
@@ -293,13 +293,12 @@ ZOOM_options_set_int(opt, name, value)
        first operation), holds the negotiated version with the server
        (same or lower version).
        </entry><entry>1.2</entry></row>
-      <row><entry>
+      <row id="zoom.facets.option"><entry>
         facets</entry><entry>
-       A FacetList is comma-separated list of facet, which is defined
-       as <literal>AttributeList</literal>  and a optional FacetTerm
-       (a Term and a frequency). On request the terms is missing.
-       On response the the list contains the terms that the target
-       could collect.
+        Requested or recommend facets may be given before a search is sent.
+        The value of this setting is described in <xref linkend="facets"/>
+        For inspection of the facets returned, refer to the functions
+        described in <xref linkend="zoom.facets"/>.
        </entry><entry>none</entry></row>
       <row><entry>
         apdulog</entry><entry>
@@ -325,6 +324,27 @@ ZOOM_options_set_int(opt, name, value)
        in call to <function>ZOOM_connection_option_get</function> or
        <function>ZOOM_connection_option_getl</function>.
        </entry><entry></entry></row>
+      <row><entry>
+        memcached</entry><entry>
+        If given and non-empty,
+        <ulink url="&url.libmemcached;">libMemcached</ulink>
+        will be configured for the connection.
+        This option is inspected by ZOOM when a connection is  established.
+        If the <literal>memcached</literal> option is given
+        and YAZ is compiled without libMemcached support, an internal
+        diagnostic (10018) will be thrown.
+        libMemcached support is available for YAZ 5.0.13 or later. If this
+        option is supplied for an earlier version of YAZ, it is
+        <emphasis>ignored</emphasis>.
+        The value of this option is a string passed verbatim to
+        the <function>memcached</function> function part of libMemcached.
+        Refer to man page
+         <ulink url="http://manned.org/memcached.3">memcached(3)</ulink>.
+        Earlier versions of libMemcached
+        do not offer this function. In this case only the option
+        <literal>--server=</literal><replaceable>host</replaceable> may
+        be given (YAZ emulates that part of libMemcached).
+       </entry><entry>none</entry></row>
      </tbody>
     </tgroup>
    </table>
@@ -1014,19 +1034,19 @@ ZOOM_options_set_int(opt, name, value)
   </sect1>
   <sect1 id="zoom.facets"><title>Facets</title>
    <para>
-    Facets operations is not part of the official ZOOM specification, but
-    is an Index Data extension for YAZ-based Z39.50 targets or
-    <ulink url="&url.solr;">Solr</ulink> targets.
-    In case the target can and is requested to return facets, using a
-    result set the ZOOM client can request one or all facet fields.
-    Using a facet field the client can request the term count and then
-    interate over the terms.
+    Facet operations is not part of the official ZOOM specification, but
+    is an Index Data extension for YAZ-based Z39.50 targets,
+    <ulink url="&url.solr;">Solr</ulink> and SRU 2.0 targets.
+
+    Facets may be requestd by the
+     <link linkend="zoom.facets.option">facets</link> option before a
+    search is sent.
+    For inspection of the returned facets, the following functions are
+    available:
    </para>
    <synopsis>
     ZOOM_facet_field *ZOOM_resultset_facets(ZOOM_resultset r);
 
-    const char ** ZOOM_resultset_facets_names(ZOOM_resultset r);
-
     ZOOM_facet_field ZOOM_resultset_get_facet_field(ZOOM_resultset r,
                                                     const char *facet_name);
 
@@ -1048,7 +1068,6 @@ ZOOM_options_set_int(opt, name, value)
     <function>ZOOM_resultset_get_facet_field</function> or
     <function>ZOOM_resultset_get_facet_field_by_index</function>.
     <function>ZOOM_resultset_facets</function>.
-    <function>ZOOM_resultset_facets_names</function>.
     <function>ZOOM_facet_field_name</function>.
     <function>ZOOM_facet_field_get_term</function>.
     </para>