-<!-- $Id: tools.xml,v 1.39 2004-11-16 17:08:11 heikki Exp $ -->
+<!-- $Id: tools.xml,v 1.54 2006-10-31 09:15:00 mike Exp $ -->
<chapter id="tools"><title>Supporting Tools</title>
<para>
<literal>@and</literal>. Its semantics are described in
section 3.7.2 (Proximity) of Z39.50 the standard itself, which
can be read on-line at
- <ulink url="http://lcweb.loc.gov/z3950/agency/markup/09.html"/>
+ <ulink url="&url.z39.50.proximity;"/>
</para>
<para>
In PQF, the proximity operation is represented by a sequence
</itemizedlist>
(The numeric values of the relation and well-known unit-code
parameters are taken straight from
- <ulink url="http://lcweb.loc.gov/z3950/agency/asn1.html#ProximityOperator"
+ <ulink url="&url.z39.50.proximity.asn1;"
>the ASN.1</ulink> of the proximity structure in the standard.)
</para>
</sect3>
<sect3 id="pqf-examples"><title>PQF queries</title>
- <example><title>PQF queries using simple terms</title>
+ <example id="example.pqf.simple.terms">
+ <title>PQF queries using simple terms</title>
<para>
<screen>
dylan
+
"bob dylan"
</screen>
</para>
</example>
- <example><title>PQF boolean operators</title>
+ <example id="pqf.example.pqf.boolean.operators">
+ <title>PQF boolean operators</title>
<para>
<screen>
@or "dylan" "zimmerman"
+
@and @or dylan zimmerman when
+
@and when @or dylan zimmerman
</screen>
</para>
</example>
- <example><title>PQF references to result sets</title>
+ <example id="example.pqf.result.sets">
+ <title>PQF references to result sets</title>
<para>
<screen>
@set Result-1
- @and @set seta setb
+
+ @and @set seta @set setb
</screen>
</para>
</example>
- <example><title>Attributes for terms</title>
+ <example id="example.pqf.attributes">
+ <title>Attributes for terms</title>
<para>
<screen>
@attr 1=4 computer
+
@attr 1=4 @attr 4=1 "self portrait"
+
@attrset exp1 @attr 1=1 CategoryList
+
@attr gils 1=2008 Copenhagen
+
@attr 1=/book/title computer
</screen>
</para>
</example>
- <example><title>PQF Proximity queries</title>
+ <example id="example.pqf.proximity">
+ <title>PQF Proximity queries</title>
<para>
<screen>
@prox 0 3 1 2 k 2 dylan zimmerman
</para></note>
</para>
</example>
- <example><title>PQF specification of search term</title>
+ <example id="example.pqf.search.term.type">
+ <title>PQF specification of search term type</title>
<para>
<screen>
@term string "a UTF-8 string, maybe?"
</screen>
</para>
</example>
- <example><title>PQF mixed queries</title>
+ <example id="example.pqf.mixed.queries">
+ <title>PQF mixed queries</title>
<para>
<screen>
@or @and bob dylan @set Result-1
license, it is included as a supplement to &yaz;.
</para>
- <sect3><title>CCL Syntax</title>
+ <sect3 id="ccl.syntax">
+ <title>CCL Syntax</title>
<para>
The CCL parser obeys the following grammar for the FIND argument.
</screen>
- <example><title>CCL queries</title>
+ <example id="example.ccl.queries">
+ <title>CCL queries</title>
<para>
The following queries are all valid:
</para>
</example>
</sect3>
- <sect3><title>CCL Qualifiers</title>
+ <sect3 id="ccl.qualifiers">
+ <title>CCL Qualifiers</title>
<para>
Qualifiers are used to direct the search to a particular searchable
lines in a CCL profile: qualifier specification,
qualifier alias, comments and directives.
</para>
- <sect4><title id="qualifier-specification">Qualifier specification</title>
+ <sect4 id="ccl.qualifier.specification">
+ <title>Qualifier specification</title>
<para>
A qualifier specification is of the form:
</para>
or <literal>c</literal> for completeness.
The attributes for the special qualifier name <literal>term</literal>
are used when no CCL qualifier is given in a query.
- <table><title>Common Bib-1 attributes</title>
+ <table id="ccl.common.bib1.attributes">
+ <title>Common Bib-1 attributes</title>
<tgroup cols="2">
<colspec colwidth="2*" colname="type"></colspec>
<colspec colwidth="9*" colname="description"></colspec>
</table>
</para>
<para>
- The complete list of Bib-1 attributes can be found
- <ulink url="http://lcweb.loc.gov/z3950/agency/defns/bib1.html">
- here
- </ulink>.
+ Refer to the complete
+ <ulink url="&url.z39.50.attset.bib1;">list of Bib-1 attributes</ulink>
</para>
<para>
It is also possible to specify non-numeric attribute values,
which are used in combination with certain types.
The special combinations are:
- <table><title>Special attribute combos</title>
+ <table id="ccl.special.attribute.combos">
+ <title>Special attribute combos</title>
<tgroup cols="2">
<colspec colwidth="2*" colname="name"></colspec>
<colspec colwidth="9*" colname="description"></colspec>
</tgroup>
</table>
</para>
- <example><title>CCL profile</title>
+ <example id="example.ccl.profile"><title>CCL profile</title>
<para>
Consider the following definition:
</para>
</para>
</example>
</sect4>
- <sect4><title>Qualifier alias</title>
+ <sect4 id="ccl.qualifier.alias">
+ <title>Qualifier alias</title>
<para>
A qualifier alias is of the form:
</para>
</para>
</sect4>
- <sect4><title>Comments</title>
+ <sect4 id="ccl.comments">
+ <title>Comments</title>
<para>
Lines with white space or lines that begin with
character <literal>#</literal> are treated as comments.
</para>
</sect4>
- <sect4><title>Directives</title>
+ <sect4 id="ccl.directives">
+ <title>Directives</title>
<para>
Directive specifications takes the form
</para>
<para><literal>@</literal><replaceable>directive</replaceable> <replaceable>value</replaceable>
</para>
- <table><title>CCL directives</title>
+ <table id="ccl.directives.table">
+ <title>CCL directives</title>
<tgroup cols="3">
<colspec colwidth="2*" colname="name"></colspec>
<colspec colwidth="8*" colname="description"></colspec>
</table>
</sect4>
</sect3>
- <sect3><title>CCL API</title>
+ <sect3 id="ccl.api">
+ <title>CCL API</title>
<para>
All public definitions can be found in the header file
<filename>ccl.h</filename>. A profile identifier is of type
</para>
</sect3>
</sect2>
- <sect2 id="tools.cql"><title>CQL</title>
+ <sect2 id="cql"><title>CQL</title>
<para>
- <ulink url="http://www.loc.gov/z3950/agency/zing/cql/">CQL</ulink>
+ <ulink url="&url.cql;">CQL</ulink>
- Common Query Language - was defined for the
- <ulink url="http://www.loc.gov/z3950/agency/zing/srw/">SRW</ulink>
- protocol.
+ <ulink url="&url.sru;">SRU</ulink> protocol.
In many ways CQL has a similar syntax to CCL.
The objective of CQL is different. Where CCL aims to be
an end-user language, CQL is <emphasis>the</emphasis> protocol
- query language for SRW.
+ query language for SRU.
</para>
<tip>
<para>
If you are new to CQL, read the
- <ulink url="http://zing.z3950.org/cql/intro.html">Gentle
- Introduction</ulink>.
+ <ulink url="&url.cql.intro;">Gentle Introduction</ulink>.
</para>
</tip>
<para>
<listitem>
<para>
The parser converts a valid CQL query to PQF, thus providing a
- way to use CQL for both SRW/SRU servers and Z39.50 targets at the
+ way to use CQL for both SRU servers and Z39.50 targets at the
same time.
</para>
</listitem>
<listitem>
<para>
The parser converts CQL to
- <ulink url="http://www.loc.gov/z3950/agency/zing/cql/xcql.html">
- XCQL</ulink>.
+ <ulink url="&url.xcql;">XCQL</ulink>.
XCQL is an XML representation of CQL.
- XCQL is part of the SRW specification. However, since SRU
+ XCQL is part of the SRU specification. However, since SRU
supports CQL only, we don't expect XCQL to be widely used.
Furthermore, CQL has the advantage over XCQL that it is
easy to read.
</listitem>
</itemizedlist>
</para>
- <sect3 id="tools.cql.parsing"><title>CQL parsing</title>
+ <sect3 id="cql.parsing"><title>CQL parsing</title>
<para>
A CQL parser is represented by the <literal>CQL_parser</literal>
handle. Its contents should be considered &yaz; internal (private).
</para>
</sect3>
- <sect3 id="tools.cql.tree"><title>CQL tree</title>
+ <sect3 id="cql.tree"><title>CQL tree</title>
<para>
The the query string is valid, the CQL parser
generates a tree representing the structure of the
If an index is unspecified for a search term,
<literal>index</literal> will be NULL.
</para>
+ </listitem>
+ <listitem>
<para>
<literal>index_uri</literal>: index URi for search term
or NULL if none could be resolved for the index.
</para>
</sect3>
- <sect3 id="tools.cql.pqf"><title>CQL to PQF conversion</title>
+ <sect3 id="cql.to.pqf"><title>CQL to PQF conversion</title>
<para>
Conversion to PQF (and Z39.50 RPN) is tricky by the fact
that the resulting RPN depends on the Z39.50 target
capabilities (combinations of supported attributes).
- In addition, the CQL and SRW operates on index prefixes
+ In addition, the CQL and SRU operates on index prefixes
(URI or strings), whereas the RPN uses Object Identifiers
for attribute sets.
</para>
</para>
<para>
If conversion failed, <function>cql_transform_buf</function>
- returns a non-zero SRW error code; otherwise zero is returned
+ returns a non-zero SRU error code; otherwise zero is returned
(conversion successful). The meanings of the numeric error
- codes are listed in the SRW specifications at
- <ulink url="http://www.loc.gov/srw/diagnostic-list.html"/>
+ codes are listed in the SRU specifications at
+ <ulink url="&url.sru.diagnostics.list;"/>
</para>
<para>
If conversion fails, more information can be obtained by calling
context set that was not recognised.
</para>
<para>
- The SRW error-codes may be translated into brief human-readable
+ The SRU error-codes may be translated into brief human-readable
error messages using
<synopsis>
const char *cql_strerror(int code);
open <literal>FILE</literal>.
</para>
</sect3>
- <sect3 id="tools.cql.map">
- <title>Specification of CQL to RPN mapping</title>
+ <sect3 id="cql.to.rpn">
+ <title>Specification of CQL to RPN mappings</title>
<para>
The file supplied to functions
<function>cql_transform_open_FILE</function>,
</varlistentry>
</variablelist>
</para>
- <example><title>CQL to RPN mapping file</title>
+ <example id="example.cql.to.rpn.mapping"><title>CQL to RPN mapping file</title>
<para>
This simple file defines two context sets, three indexes and three
relations, a position pattern and a default structure.
</screen>
</para>
</example>
+ <example id="example.cql.to.rpn.bathprofile">
+ <title>CQL to RPN using Bath Profile</title>
+ <para>
+ The file <filename>etc/pqf.properties</filename> has mappings from
+ the Bath Profile and Dublin Core to RPN.
+ If YAZ is installed as a package it's usually located
+ in <filename>/usr/share/yaz/etc</filename> and part of the
+ development package, such as <literal>libyaz-dev</literal>.
+ </para>
+ </example>
</sect3>
- <sect3 id="tools.cql.xcql"><title>CQL to XCQL conversion</title>
+ <sect3 id="cql.xcql"><title>CQL to XCQL conversion</title>
<para>
Conversion from CQL to XCQL is trivial and does not
require a mapping to be defined.
<para>
again, corresponding to the specific OIDs defined by the standard.
Refer to the
- <ulink url="http://lcweb.loc.gov/z3950/agency/defns/oids.html">
+ <ulink url="&url.z39.50.oids;">
Registry of Z39.50 Object Identifiers</ulink> for the
whole list.
</para>
<sect1 id="tools.log"><title>Log</title>
<para>
- Yaz has evolved a fairly complex log system which should be useful both
- for debugging &yaz; itself, debugging applications that use yaz, and for
+ &yaz; has evolved a fairly complex log system which should be useful both
+ for debugging &yaz; itself, debugging applications that use &yaz;, and for
production use of those applications.
</para>
<para>
- The log functions are declared in <filename>log.h</filename> and
- implemented in <filename>log.c</filename>. The key points of the interface
- are:
+ The log functions are declared in header <filename>yaz/log.h</filename>
+ and implemented in <filename>src/log.c</filename>.
+ Due to name clash with syslog and some math utilities the logging
+ interface has been modified as of YAZ 2.0.29. The obsolete interface
+ is still available if in header file <filename>yaz/log.h</filename>.
+ The key points of the interface are:
</para>
<screen>
void yaz_log(int level, const char *fmt, ...)
<para>
The <literal>log level</literal> is a bit mask, that says on which level(s)
the log entry should be made, and optionally set some behaviour of the
- logging. In the most simple cases, it can be one of <literal>LOG_FATAL,
- LOG_DEBUG, LOG_WARN, LOG_LOG</literal>. Those can be combined with bits
- that modify the way the log entry is written:<literal>LOG_ERRNO, LOG_NOTIME,
- LOG_FLUSH</literal>. Most of the rest of the bits are deprecated, and
- should not be used.
+ logging. In the most simple cases, it can be one of <literal>YLOG_FATAL,
+ YLOG_DEBUG, YLOG_WARN, YLOG_LOG</literal>. Those can be combined with bits
+ that modify the way the log entry is written:<literal>YLOG_ERRNO,
+ YLOG_NOTIME, YLOG_FLUSH</literal>.
+ Most of the rest of the bits are deprecated, and should not be used. Use
+ the dynamic log levels instead.
</para>
<para>
- Applications that use yaz, should not use the LOG_LOG for ordinary
+ Applications that use &yaz;, should not use the LOG_LOG for ordinary
messages, but should make use of the dynamic loglevel system. This consists
of two parts, defining the loglevel and checking it.
</para>
<function>yaz_log_mask_str</function> to define which log levels are to be
logged. This string should be a comma-separated list of log level names,
and can contain both hard-coded names and dynamic ones. The log level
- calculation starts with <literal>LOG_DEFAULT_LEVEL</literal> and adds a bit
- for each word it meets. If the string <literal>'none'</literal> is found,
- the bits are cleared. Typically this string comes from the command-line,
+ calculation starts with <literal>YLOG_DEFAULT_LEVEL</literal> and adds a bit
+ for each word it meets, unless the word starts with a '-', in which case it
+ clears the bit. If the string <literal>'none'</literal> is found,
+ all bits are cleared. Typically this string comes from the command-line,
often identified by <literal>-v</literal>. The
<function>yaz_log_mask_str</function> returns a log level that should be
passed to <function>yaz_log_init_level</function> for it to take effect.
</para>
<para>
+ Yaz uses the following dynamic log levels:
+ <literal>server, session, request, requestdetail</literal> for the server
+ functionality.
+ <literal>zoom</literal> for the zoom client api.
+ <literal>ztest</literal> for the simple test server.
+ <literal>malloc, nmem, odr, eventl</literal> for internal debugging of yaz itself.
+ Of course, any program using yaz is welcome to define as many new ones, as
+ it needs.
+ </para>
+
+ <para>
By default the log is written to stderr, but this can be changed by a call
to <function>yaz_log_init_file</function> or
<function>yaz_log_init</function>. If the log is directed to a file, the
rotation feature.
</para>
+ <screen>
+ A typical yaz-log looks like this
+ 13:23:14-23/11 yaz-ztest(1) [session] Starting session from tcp:127.0.0.1 (pid=30968)
+ 13:23:14-23/11 yaz-ztest(1) [request] Init from 'YAZ' (81) (ver 2.0.28) OK
+ 13:23:17-23/11 yaz-ztest(1) [request] Search Z: @attrset Bib-1 foo OK:7 hits
+ 13:23:22-23/11 yaz-ztest(1) [request] Present: [1] 2+2 OK 2 records returned
+ 13:24:13-23/11 yaz-ztest(1) [request] Close OK
+ </screen>
+
<para>
The log entries start with a time stamp. This can be omitted by setting the
- <literal>LOG_NOTIME</literal> bit in the loglevel. This way automatic tests
+ <literal>YLOG_NOTIME</literal> bit in the loglevel. This way automatic tests
can be hoped to produce identical log files, that are easy to diff. The
format of the time stamp can be set with
<function>yaz_log_time_format</function>, which takes a format string just
</para>
<para>
- Next in a log line comes the prefix, often the name of the program. Then
+ Next in a log line comes the prefix, often the name of the program. For
+ yaz-based servers, it can also contain the session number. Then
comes one or more logbits in square brackets, depending on the logging
level set by <function>yaz_log_init_level</function> and the loglevel
- passed to <function>yaz_log_init_level</function>. Finally comes all format
+ passed to <function>yaz_log_init_level</function>. Finally comes the format
string and additional values passed to <function>yaz_log</function>
</para>
<para>
- The log level <literal>LOG_LOGLVL</literal>, enabled by the string
+ The log level <literal>YLOG_LOGLVL</literal>, enabled by the string
<literal>loglevel</literal>, will log all the log-level affecting
operations. This can come in handy if you need to know what other log
levels would be useful. Grep the logfile for <literal>[loglevel]</literal>.
</para>
<para>
- The dynamic log levels and log rotation were introduced in &yaz; 2.0.28.
+ The dynamic log levels and log rotation were introduced in &yaz; 2.0.28. At
+ the same time, the log bit names were changed from
+ <literal>LOG_something</literal> to <literal>YLOG_something</literal>,
+ to avoid collision with <filename>syslog.h</filename>.
</para>
</sect1>
- <sect1 id="tools.marc"><title>MARC</title>
+ <sect1 id="marc"><title>MARC</title>
<para>
YAZ provides a fast utility that decodes MARC records and
#define YAZ_MARC_OAIMARC 2
#define YAZ_MARC_MARCXML 3
#define YAZ_MARC_ISO2709 4
+ #define YAZ_MARC_XCHANGE 5
/* supply iconv handle for character set conversion .. */
void yaz_marc_iconv(yaz_marc_t mt, yaz_iconv_t cd);
</varlistentry>
<varlistentry>
- <term>YAZ_MARC_MARXML</term>
+ <term>YAZ_MARC_MARCXML</term>
<listitem>
<para>
The resulting record is converted to MARCXML.
stores the resulting record in a WRBUF handle (WRBUF is a simple string
type).
</para>
- <example>
+ <example id="example.marc.display">
<title>Display of MARC record</title>
<para>
The followint program snippet illustrates how the MARC API may
projects / yaz-moved-to-github.git / blobdiff