<section id="proxy-operation">
<title>Operating Environment</title>
<para>
- The YAZ proxy is a single program. After startup it spawns
+ The YAZ proxy is a console program. After startup it spawns
a child process (except on Windows or if option -X is given).
The child process is the core of the proxy and it handles all
communication with clients and servers. The parent process
see <xref linkend="proxy-usage"/>.
</para>
<para>
- As an option the proxy may change user identity to a less privileged
+ As an option, the proxy may change user identity to a less privileged
user.
</para>
</section>
</para>
</section>
+
+ <section id="query-cache">
+ <title>Query Caching</title>
+ <para>
+ Simple stateless clients often send identical Z39.50 searches
+ in a relatively short period of time (e.g. in order to produce a
+ results-list page, the next page,
+ a single full-record, etc). And for many targets, it's
+ much more expensive to produce a new result set than to
+ reuse an existing one.
+ </para>
+ <para>
+ The proxy tries to solve that by remembering the last query for each
+ backend target, so that if an identical query is received next, it
+ is turned into Present Requests rather than new Search Requests.
+ </para>
+ <note>
+ <para>
+ In a future we release will will probably allows for
+ an arbitrary-sized cache for targets supporting named result sets.
+ </para>
+ </note>
+ <para>
+ You can enable/disable query caching using option -o.
+ </para>
+ </section>
+
+ <section id="record-cache">
+ <title>Record Caching</title>
+ <para>
+ As an option, the proxy may also cache result set records for the
+ last search.
+ The proxy takes into account the Record Syntax and CompSpec.
+ The CompSpec includes simple element set names as well.
+ By default the cache is 200000 bytes per session.
+ </para>
+ </section>
+
+ <section id="query-validation">
+ <title>Query Validation</title>
+ <para>
+ The Proxy may also be configured to trap particular attributes in
+ Type-1 queries and send Bib-1 diagnostics back to the client without
+ even consulting the backend target. This facility may be useful if
+ a target does not properly issue diagnostics when unsupported attributes
+ are send to it.
+ </para>
+ </section>
+
+ <section id="record-validation">
+ <title>Record Syntax Validation</title>
+ <para>
+ The proxy may be configured to accept, reject or convert records.
+ When accepted, the target passes search/present requests to the
+ backend target under the assumption that the target can honor the
+ request (In fact it may not do that). When a record is rejected because
+ the record syntax is "unsupported" the proxy returns a diagnostic to the
+ client. Finally, the proxy may convert records.
+ </para>
+ <para>
+ The proxy can convert from MARC to MARCXML and thereby offer an
+ XML version of any MARC record as long as it is ISO2709 encoded.
+ If the proxy is compiled with libXSLT support it can also
+ perform XSLT on XML.
+ </para>
+ </section>
+
+ <section id="other-optimizations">
+ <title>Other Optimizations</title>
+ <para>
+ We've had some plans to support global caching of result set records,
+ but this has not yet been implemented.
+ </para>
+ </section>
+
<section id="proxy-config-file">
<title>Proxy Configuration File</title>
<para>
</para>
<para>
This can also be specified on the command line by using option
- <literal>-T</literal>. Refer to OPTIONS.
+ <literal>-T</literal>. Refer to OPTIONS in <xref linkend="proxy-usage"/>.
</para>
</section>
</para>
<para>
This can also be specified on the command line by using option
- <literal>-i</literal>. Refer to OPTIONS.
+ <literal>-i</literal>. Refer to OPTIONS in <xref linkend="proxy-usage"/>.
</para>
</section>
A target that supports use attributes 1,4, 1000 through 1003 and
no other use attributes, could use the following rules:
<screen>
- <attribute type="1" value="1,4,1000-1003">
+ <attribute type="1" value="1,4,1000-1003"/>
<attribute type="1" value="*" error="114"/>
</screen>
</para>
..
<syntax type="usmarc"/>
<syntax type="xml" marcxml="1"
- identifier="info:srw/schema/1/marcxml-v1.1"
- <title>MARCXML<title>
- <name>marcxml<name>
- <syntax>
+ identifier="info:srw/schema/1/marcxml-v1.1"
+ <title>MARCXML<title>
+ <name>marcxml<name>
+ </syntax>
<syntax type="xml" marcxml="1" stylesheet="MARC21slim2SRWDC.xsl"
- identifier="info:srw/schema/1/dc-v1.1">
- <title>Dublin Core<title>
- <name>dc<name>
- <syntax>
+ identifier="info:srw/schema/1/dc-v1.1">
+ <title>Dublin Core<title>
+ <name>dc<name>
+ </syntax>
<syntax type="*" error="238"/>
..
</target>
</para>
</section>
</section>
-
- <section id="query-cache">
- <title>Query Caching</title>
- <para>
- Simple stateless clients often send identical Z39.50 searches
- in a relatively short period of time (e.g. in order to produce a
- results-list page, the next page,
- a single full-record, etc). And for many targets, it's
- much more expensive to produce a new result set than to
- reuse an existing one.
- </para>
- <para>
- The proxy tries to solve that by remembering the last query for each
- backend target, so that if an identical query is received next, it
- is turned into Present Requests rather than new Search Requests.
- </para>
- <note>
- <para>
- In a future we release will will probably allows for
- an arbitrary-sized cache for targets supporting named result sets.
- </para>
- </note>
- <para>
- You can enable/disable query caching using option -o.
- </para>
- </section>
-
- <section id="record-cache">
- <title>Record Caching</title>
- <para>
- As an option, the proxy may also cache result set records for the
- last search.
- The proxy takes into account the Record Syntax and CompSpec.
- The CompSpec includes simple element set names as well.
- By default the cache is 200000 bytes per session.
- </para>
- </section>
-
- <section id="query-validation">
- <title>Query Validation</title>
- <para>
- The Proxy may also be configured to trap particular attributes in
- Type-1 queries and send Bib-1 diagnostics back to the client without
- even consulting the backend target. This facility may be useful if
- a target does not properly issue diagnostics when unsupported attributes
- are send to it.
- </para>
- </section>
-
- <section id="record-validation">
- <title>Record Syntax Validation</title>
- <para>
- The proxy may be configured to accept, reject or convert records.
- When accepted, the target passes search/present requests to the
- backend target under the assumption that the target can honor the
- request (In fact it may not do that). When a record is rejected because
- the record syntax is "unsupported" the proxy returns a diagnostic to the
- client. Finally, the proxy may convert records.
- </para>
- <para>
- The proxy can convert from MARC to MARCXML and thereby offer an
- XML version of any MARC record as long as it is ISO2709 encoded.
- If the proxy is compiled with libXSLT support it can also
- perform XSLT on XML.
- </para>
- </section>
-
- <section id="other-optimizations">
- <title>Other Optimizations</title>
- <para>
- We've had some plans to support global caching of result set records,
- but this has not yet been implemented.
- </para>
- </section>
-
<section id="proxy-usage">
<title>Proxy Usage (man page)</title>
<refentry id="yazproxy-man">
directory <filename>etc</filename> of the distribution.
</para>
<screen><![CDATA[
- <?xml version="1.0"?>
+<?xml version="1.0"?>
<!-- XML Schema for YAZ proxy config file.
- $Id: reference.xml,v 1.4 2004-04-21 08:16:42 adam Exp $
+ $Id: reference.xml,v 1.7 2004-07-02 12:44:33 adam Exp $
-->
<xs:schema
xmlns:xs="http://www.w3.org/2001/XMLSchema"
<xs:element ref="attribute" minOccurs="0" maxOccurs="unbounded"/>
<xs:element ref="syntax" minOccurs="0" maxOccurs="unbounded"/>
<xs:element ref="preinit" minOccurs="0"/>
- <xs:element name="exp:explain" minOccurs="0"/>
+ <xs:element ref="exp:explain" minOccurs="0"/>
<xs:element ref="cql2rpn" minOccurs="0"/>
</xs:sequence>
<xs:attribute name="default" type="xs:string" use="optional"/>
<xs:element name="syntax">
<xs:complexType>
<xs:sequence>
- <xs:element name="title" type="xs:string" minOccurs="0"/>
- <xs:element name="name" type="xs:string" minOccurs="0"
- maxOccurs="unbounded"/>
+ <xs:element ref="title" minOccurs="0"/>
+ <xs:element ref="name" minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
- <xs:attribute name="error" type="xs:string" minOccurs="0"/>
- <xs:attribute name="type" type="xs:string" minOccurs="0"/>
- <xs:attribute name="marcxml" type="xs:string" minOccurs="0"/>
- <xs:attribute name="identifier" type="xs:string" minOccurs="0"/>
- <xs:attribute name="stylesheet" type="xs:string" minOccurs="0"/>
+ <xs:attribute name="error" type="xs:string" />
+ <xs:attribute name="type" type="xs:string" />
+ <xs:attribute name="marcxml" type="xs:string" />
+ <xs:attribute name="identifier" type="xs:string" />
+ <xs:attribute name="stylesheet" type="xs:string" />
</xs:complexType>
</xs:element>
+ <xs:element name="title" type="xs:string"/>
+ <xs:element name="name" type="xs:string"/>
+
<xs:element name="max-clients" type="xs:integer"/>
<xs:element name="log" type="xs:string"/>
</xs:schema>
-
]]>
</screen>
</section>
projects / yazproxy-moved-to-github.git / blobdiff